(8:30PM - 2/20/22) A brief recap of the Sun, Feb 20th high wind episode that affected the state and region.

Recap Summary...
​A storm system quickly moved through the region, on Sun Feb 20th. This storm system tracked from the Southern Canada Prairies Saturday night, through the Northern Midwest and Northern Great Lakes on Sunday, and then into Southeastern Canada Sunday night. This storm system brought a high wind episode to portions of the state and region.

​Event Recap...
​Early Sunday Morning - Late Sunday Afternoon, Feb 20th...
As ​a storm system tracked from the Southern Canada Prairies Saturday night, through the Northern Midwest and Northern Great Lakes on Sunday, and then into Southeastern Canada Sunday night...It was accompanied by a strong jet streak aloft as well. High winds aloft characterized by a low level jet (850mb) of 55-85KT and 925mb winds of 55-75KT, translated through the region with the storm system. Adequate mixing occurred, at least up to 925mb, which transported higher winds to the surface. During this period, wind gusts of 35-55MPH occurred across a large portion of the state.

Below is a list of measured/observed peak wind gusts across the state during this event.

JP

(12:30PM - 2/20/22) A brief recap of the Fri-Sat, Feb 18-19th high wind episode that affected the state and region.

Recap Summary...
​A storm system quickly moved through the region, Friday through Saturday Feb 18-19th. This storm system tracked from the Southern Canada Prairies Thursday night, through the Northern Midwest and Northern Great Lakes on Friday, and then into the Northeast Saturday morning. This storm system brought a high wind episode to portions of the state and region.

​Event Recap...
​Early Friday Afternoon - Early Saturday Morning, Feb 18-19th...
As ​a storm system tracked from the Southern Canada Prairies Thursday night, through the Northern Midwest and Northern Great Lakes on Friday, and then into the Northeast Saturday morning...It was accompanied by a strong jet streak aloft as well. High winds aloft characterized by a low level jet (850mb) of 45-65KT and 925mb winds of 35-55KT, translated through the region with the storm system. Adequate mixing occurred, at least up to 925mb, which transported higher winds to the surface. Additionally, as the cold front associated with the storm system moved through it was accompanied by a significant snow squall, which produced isolated higher wind gusts. During this period, wind gusts of 35-55MPH occurred across Northern and portions of Central Illinois.

Below is a list of measured/observed peak wind gusts across the state during this event.

JP

​(9:00AM Thursday - 2/17/22) A winter storm will continue to impact the region and state, this evening. This winter storm will produce a swath of accumulating snow/sleet/ice, heavy rainfall with localized to scattered flooding potential, and an isolated severe t'storm risk across the region and state during this time.

Summary...
A winter storm continues to affect the state and region today. Even as this winter storm is unfolding and an overall consensus solution had been in place within model guidance, there still has and continues to be some disagreement on how things will continue to unfold today regarding this winter storm. With that said, the overall going forecast is on track with some minor adjustments needed based on real time observations. These real time observations support the overall forecast, and consensus solution on hi-res/short term model guidance.

​A cold front that moved through the region Wednesday and Wednesday night associated with a storm system moving through Southern Canada stalled out near the Ohio Valley in the region and Southern Illinois. A storm system developed in the Southern Plains Wednesday night, and will be tracking through the Ohio Valley today, and eventually into the Northeast on Friday. This storm system is bringing a renewed push of precipitation and main impacts of this period across the region and state, this morning through this evening.

​Wintry (Snow/Sleet/Ice) Aspect Forecast...
This Morning - This Evening, Feb 17th ~ Main Winter Storm Event:
​As the main storm system is moving through the region today, an associated renewed push of precipitation is also moving across the state and region with the main impacts expected, this morning through this evening. This renewed push of precipitation, in the form of snow/sleet/freezing rain/rain has been spreading into West-Central and Southwestern Illinois this morning. This area of precipitation will continue to spread across portions of Northern and all of Central Illinois through late this afternoon, before ending this evening. A transition zone has set up and will be in place much of the day today across portions of Central Illinois, generally near and between I-72 and I-70. Across this zone, precipitation types will from south to north will range from freezing rain to sleet to snow. This transition zone will eventually change over to snow for a time, before precipitation ends this evening. North of this transition zone across affected areas of Northern and Central Illinois (Near/north of I-72), most precipitation will fall as snow. Periods of moderate to heavy snow is likely at times, with snowfall rates of 1-2" an hour likely at times. Additionally, windy conditions are expected this morning into this evening across a large portion of the state. During this time wind gusts upwards of 20-40MPH will be possible, which will cause some blowing and drifting snow for areas experiencing snow and near blizzard conditions at times. 

​Below are the snowfall and ice forecasts for this winter storm.

​Severe T'Storm Risk/Heavy Rain/Flooding Aspect Forecast...
This Morning - This Afternoon, Feb 17th ~ Severe T'Storm Event:
​The main risk for an isolated severe t'storm risk will exist across far Southern Illinois, this morning through this afternoon. Areas of rain and isolated to scattered t'storms have been ongoing this morning across Southern Illinois, in the vicinity of a nearly stationary frontal boundary in place. An isolated severe t'storm cannot be ruled out with this activity. As the main storm system moves through the region today, an arc of rain and t'storms will accompany the low pressure and cold front that sweeps across Southern Illinois, this morning through this afternoon. Ahead of this activity, an environment will be in place supportive of some severe t'storm risk with this activity. This environment will feature marginal instability of up to 500J/KG, dew points in the low 50's to around 60, good shear, good forcing, and modest lapse rates of 5.0-7.0C. This environment will be supportive of upwards of an isolated severe t'storm risk (levels 1) across far Southern Illinois. It should eb stressed that this is a very low and very isolated severe t'storm risk. Damaging winds, hail and an isolated tornado will be the severe weather threats.

Wed Afternoon - This Evening, Feb 16-17th ~ Heavy Rain/Flooding Event:
Persistent periods of rainfall have been occurring across the southern half of the state since yesterday afternoon, with additional periods of rainfall expected to continue through later this afternoon. This activity is associated both with a frontal boundary becoming stationary across Southern Illinois and the main storm system moving through. During this period of time, periods of heavier rainfall will be possible. Rainfall totals of 1-3" have already occurred across the southern half of the state, with some reports of localized flooding. Including additional rainfall expected, widespread final rainfall totals of 1-4" are expected across the southern half of the state during this period of time, with locally higher amounts possible. Due to the combination of frost depth/frozen ground and the expected rainfall, localized to scattered flooding is likely across the southern half of the state. Further north across Northern and Central Illinois, rainfall totals of 0.50-1.50" occurred Wednesday afternoon through early this morning, which lead to some instances of localized/minor flooding, due to frozen ground not being able to absorb lingering snow melt and rainfall.

Below are the severe t'storm and heavy rain/flooding forecast for this winter storm.

​Impacts...
-An axis of of snow/sleet accumulation of 2-5" to 4-7" across portions of Northern and Central Illinois, with locally higher amounts possible. Snowfall amounts will taper north and south of this main axis.
-Ice accumulations of a glaze (Up to 0.10") across a large portion of the state, with an axis of localized 0.10"+ ice accumulation across the heart of the state.
​-An isolated severe t'storm threat across Southern Illinois, this morning through this afternoon.
-Widespread heavy rainfall across the southern half of the state, with widespread rainfall totals of 1-4" expected. These rainfall totals will cause localized to scattered flooding potential for affected areas.
-Widespread travel impacts likely across much of the state, through this evening.

JP

(10:30PM Wednesday - 2/16/22) A winter storm will continue to impact the region and state, tonight through Thursday evening. This winter storm is expected to produce a swath of accumulating snow/sleet/ice, heavy rainfall with minor flooding potential, and an isolated severe t'storm risk across the region and state during this time.

Summary...
Over the past several days model guidance has been honing in on the potential for a winter storm to affect the region and state through Thursday. A large majority of model guidance has shown a consensus solution for the past day or so, and lingering outlier model guidance has finally come into agreement as well. Even so, as the winter storm continues to unfold some changes to the forecast are still possible. Stay tuned to updates over the next several days regarding this winter storm.

​A cold front has been moving through the region today and will continue to tonight, associated with a storm system moving through Southern Canada. This frontal boundary will become nearly stationary by Thursday morning, near the Ohio Valley in the region and Southern Illinois. Furthermore, a storm system will develop in the Southern Plains tonight, and will then track through the Ohio Valley on Thursday, and eventually into the Northeast on Friday. This storm system will bring a renewed push of precipitation and main impacts of this period across the region and state, Thursday morning through Thursday evening.

​Wintry (Snow/Sleet/Ice) Aspect Forecast...
Tonight - Thursday Morning, Feb 16-17th ~ Cold Front/Lead Wave Event:
A cold front has been moving through the region today and will continue to tonight, associated with a storm system moving through Southern Canada. This frontal boundary will then become nearly stationary by Thursday morning, near the Ohio Valley in the region and Southern Illinois. Precipitation in the form of rain developed ahead of the cold front, across portions of Missouri, Iowa, Northern/Central Illinois and Wisconsin this afternoon. This area of rain continued to expand as it further developed and pushed northeastward, spreading into other portions of Northern and Central Illinois this afternoon and evening. This activity will continue across Northern and Central Illinois tonight, and has also started to push into Southern Illinois as well early tonight with it expected to continue overnight tonight. Isolated to scattered t'storms will be possible with this activity across much of the state through tonight. Colder air has started to filter in behind the cold front across Northern and Western Illinois, with this expected colder air expected to continue to push southward behind the cold front overnight tonight. As this colder air filters in, rain will transition to a mix of rain/freezing rain/sleet/snow across portions of Northern and Western Illinois overnight tonight, and then continuing into Thursday morning. Some snow/sleet/ice accumulation will be possible across portions of affected areas of Northern and Western Illinois, tonight into Thursday morning. Windy conditions featuring wind gusts of 30-45MPH that had been in place much of the day across the state have subsided this evening, with winds remaining lighter overnight tonight.

Thursday Morning - Thursday Evening, Feb 17th ~ Main Winter Storm Event:
​As the main storm system moves through the region, an associated renewed push of precipitation will move across the state and region with the main impacts expected, Thursday morning through Thursday evening. This renewed push of precipitation, in the form of snow/sleet/ice, will move into Western Illinois by mid morning Thursday. This area of precipitation will then spread across portions of Northern and all of Central Illinois late Thursday morning through mid Thursday afternoon, before ending Thursday evening. A transition zone will set up much of the day on Thursday across portions of Central Illinois, generally between I-72 and I-70. Across this zone, precipitation types will from south to north will range from freezing rain to sleet to snow. This transition zone will eventually change over to snow for a time, before precipitation ends between mid Thursday afternoon into Thursday evening. North of this transition zone across affected areas of Northern and Central Illinois, most precipitation will fall as snow. Periods of moderate to heavy snow will be possible at times, with snowfall rates of 1"+ an hour likely at times. Additionally, windy conditions are expected Thursday morning into Thursday evening across a large portion of the state. During this time wind gusts upwards of 20-40MPH will be possible, which will cause some blowing and drifting snow for areas experiencing snow. 

​Below are the snowfall and ice forecasts for this winter storm.

​Severe T'Storm Risk/Heavy Rain/Flooding Aspect Forecast...
Thursday Morning - Thursday Evening, Feb 17th ~ Severe T'Storm Event:
​The main risk for an isolated severe t'storm risk will exist across far Southern Illinois, Thursday morning into Thursday afternoon. Areas of rain and isolated to scattered t'storms will be ongoing Thursday morning across Southern Illinois, in the vicinity of a nearly stationary frontal boundary in place. An isolated severe t'storm cannot be ruled out with this activity. As the main storm system moves through the region, an arc of rain and t'storms will accompany the low pressure and cold front that sweeps across Southern Illinois, Thursday morning into Thursday afternoon. Ahead of this activity, an environment will be in place supportive of some severe t'storm risk with this activity. This environment will feature marginal instability of up to 500J/KG, dew points in the mid 50's to low 60's, good shear, good forcing, and modest lapse rates of 5.0-7.0C. This environment will be supportive of upwards of an isolated severe t'storm risk (levels 1) across far Southern Illinois. Damaging winds, hail and an isolated tornado will be the severe weather threats.

This Afternoon - Thursday Evening, Feb 16-17th ~ Heavy Rain/Flooding Event:
Persistent periods of rainfall are expected across the southern half of the state tonight through Thursday afternoon, associated both with a frontal boundary becoming stationary across Southern Illinois and the main storm system moving through. During this period of time, periods of heavier rainfall will be possible. Widespread rainfall totals of 1-3" are expected across the southern half of the state during this period of time, with locally higher amounts possible. Due to the combination of frost depth/frozen ground and the expected rainfall, some localized/minor flooding will be possible for some areas. Further north across Northern and Central Illinois, rainfall totals of 0.50-2.00" through early Thursday morning could lead to some instances of localized/minor flooding potential, due to frozen ground not being able to absorb lingering snow melt and rainfall.

Below are the severe t'storm and heavy rain/flooding forecast for this winter storm.

​​Impacts...
-An axis of of snow/sleet accumulation of 2-5" to 4-7" across portions of Northern and Central Illinois, with locally higher amounts likely. Snowfall amounts will taper north and south of this main axis.
-Ice accumulations of a glaze (Up to 0.10") across much of the state, with an axis of 0.10-0.25"+ ice accumulation across the heart of the state.
​-An isolated severe t'storm threat across Southern Illinois, Thursday morning through Thursday afternoon.
-Widespread heavy rainfall across the southern half of the state, with widespread rainfall totals of 1-4" expected. These rainfall totals could cause localized/minor flooding potential for affected areas.
-Widespread travel impacts likely across much of the state, Wednesday night through Thursday evening.

JP

(11:45AM - 2/16/22) A winter storm is set to impact the region and state, midday today through Thursday evening. This winter storm is expected to produce a swath of accumulating snow/sleet/ice, heavy rainfall with minor flooding potential, and an isolated severe t'storm risk across the region and state during this time.

Summary...
Over the past several days model guidance has been honing in on the potential for a winter storm to affect the region and state, today through Thursday. While a large majority of model guidance has shown a consensus solution for the past day or so, there was still some disagreement within some guidance. However, much of the remaining outlier guidance has also finally shifted to the main consensus solution. Even so, as the winter storm continues to unfold some changes to the forecast are still possible. Stay tuned to updates over the next several days regarding this winter storm.

​A cold front will move through the region today and tonight, associated with a storm system moving through Southern Canada. This frontal boundary will then become nearly stationary by Thursday morning, near the Ohio Valley in the region and Southern Illinois. Furthermore, a storm system will develop in the Southern Plains tonight, and will then track through the Ohio Valley on Thursday, and eventually into the Northeast on Friday. This storm system will bring a renewed push of precipitation and main impacts of this period across the region and state, Thursday morning through Thursday evening.

Wintry (Snow/Sleet/Ice) Aspect Forecast...
This Afternoon - Thursday Morning, Feb 16-17th ~ Cold Front/Lead Wave Event:
A cold front will move through the region today and tonight, associated with a storm system moving through Southern Canada. This frontal boundary will then become nearly stationary by Thursday morning, near the Ohio Valley in the region and Southern Illinois. Precipitation in the form of rain will develop along and ahead of the cold front, across portions of Missouri, Iowa, Northern/Central Illinois and Wisconsin around midday today into early this afternoon. This area of rain will expand as it further develops and pushes northeastward, spreading into other portions of Northern and Central Illinois this afternoon and evening, and eventually into Southern Illinois as well late this evening and into tonight. Isolated to scattered t'storms will be possible with this activity across much of the state, this afternoon into tonight. As colder air filters in behind the slowing cold front pushing through the state, rain will transition to a mix of rain/freezing rain/sleet/snow across portions of Northern and Western Illinois late this evening and into Wednesday night, and then continuing into Thursday morning. Some snow/sleet/ice accumulation will be possible across portions of affected areas of Northern and Western Illinois, tonight into Thursday morning. In addition to precipitation, wind conditions are expected across much of the state today, with wind gusts of 20-40MPH being likely through this evening for much of the state, with locally higher wind gusts in excess of 40MPH being possible.

Thursday Morning - Thursday Evening, Feb 17th ~ Main Winter Storm Event:
​As the main storm system moves through the region, an associated renewed push of precipitation will move across the state and region with the main impacts expected, Thursday morning through Thursday evening. This renewed push of precipitation, in the form of snow/sleet/ice, will move into Western Illinois early to mid morning Thursday. This area of precipitation will then spread across portions of Northern and all of Central Illinois late Thursday morning through mid Thursday afternoon, before ending Thursday evening. A transition zone will set up much of the day on Thursday across portions of Central Illinois. Across this zone, precipitation types will from south to north will range from freezing rain to sleet to snow. This transition zone will eventually change over to snow as precipitation ends mid Thursday afternoon into Thursday evening. North of this transition zone across affected areas of Northern and Central Illinois, most precipitation will fall as snow. Periods of moderate to heavy snow will be possible at times, with snowfall rates of 1"+ an hour likely at times. Additionally, windy conditions are expected Thursday morning into Thursday evening across a large portion of the state. During this time wind gusts upwards of 20-40MPH will be possible, which will cause some blowing and drifting snow for areas experiencing snow. 

​Below are the snowfall and ice forecasts for this winter storm.

​Severe T'Storm Risk/Heavy Rain/Flooding Aspect Forecast...
Thursday Morning - Thursday Evening, Feb 17th ~ Severe T'Storm Event:
​The main risk for an isolated severe t'storm risk will exist across far Southern Illinois, Thursday morning into Thursday afternoon. Areas of rain and isolated t'storms will be ongoing Thursday morning across Southern Illinois, in the vicinity of a nearly stationary frontal boundary in place. As the main storm system moves through the region, an arc of rain and t'storms will accompany the low pressure and cold front that sweeps across Southern Illinois, Thursday morning into Thursday afternoon. Ahead of this activity, an environment will be in place supportive of some severe t'storm risk with this activity. This environment will feature marginal instability of up to 500J/KG, dew points in the mid 50's to low 60's, good shear, good forcing, and modest lapse rates of 5.0-7.0C. This environment will be supportive of upwards of an isolated severe t'storm risk (levels 1) across far Southern Illinois. Damaging winds, hail and an isolated tornado will be the severe weather threats.

This Afternoon - Thursday Evening, Feb 16-17th ~ Heavy Rain/Flooding Event:
Persistent periods of rainfall are expected across the southern half of the state this afternoon through Thursday afternoon, associated both with a frontal boundary becoming stationary across Southern Illinois and the main storm system moving through. During this period of time, periods of heavier rainfall will be possible. Widespread rainfall totals of 1-3" are expected across the southern half of the state during this period of time. Due to the combination of frost depth/frozen ground and the expected rainfall, some widespread minor flooding will be possible for some areas. Further north across Northern and Central Illinois, rainfall totals of 0.50-2.00" this afternoon through tonight could lead to localized flooding potential, due to frozen ground not being able to absorb lingering snow melt and rainfall.

Below are the severe t'storm and heavy rain/flooding forecast for this winter storm.

​Impacts...
-An axis of of snow/sleet accumulation of 2-5" to 4-7" across portions of Northern and Central Illinois, with locally higher amounts likely. Snowfall amounts will taper north and south of this main axis.
-Ice accumulations of a glaze (Up to 0.10") across much of the state, with an axis of 0.10-0.25"+ ice accumulation across the heart of the state.
​-An isolated severe t'storm threat across Southern Illinois, Thursday morning through Thursday afternoon.
-Widespread heavy rainfall across the southern half of the state, with widespread rainfall totals of 1-3" expected. These rainfall totals could cause minor/localized flooding potential for affected areas.
-Widespread travel impacts likely across much of the state, Wednesday night through Thursday evening.

JP

(10:30PM - 2/15/22) A winter storm is set to impact the region and state, midday Wednesday through Thursday evening. This winter storm is expected to produce a swath of accumulating snow/sleet/ice, heavy rainfall with minor flooding potential, and an isolated severe t'storm risk across the region and state during this time.

Summary...
Over the past several days model guidance has been honing in on the potential for a winter storm to affect the region and state, Wednesday through Thursday. While there continues to be some model guidance disagreement regarding this storm system at this time, a large majority of model guidance continues to show a consensus solution, which is what our current forecast is based around. As stated, there still does continue to be some disagreement within model guidance at this time, so some changes to the forecast can be expected until full agreement on the situation is reached. Stay tuned to updates over the next several days regarding this winter storm.

​A cold front will move through the region Wednesday and Wednesday night, associated with a storm system moving through Southern Canada. This frontal boundary will then become nearly stationary across the region and southern half of the state, Thursday morning. Furthermore, a storm system will develop in the Southern Plains Wednesday night, and will then track through the Ohio Valley on Thursday, and eventually into the Northeast on Friday. This storm system will bring a renewed push of precipitation and main impacts of this period across the region and state, Thursday morning through Thursday evening.

​Wintry (Snow/Sleet/Ice) Aspect Forecast...
Wednesday Afternoon - Thursday Morning, Feb 16-17th ~ Cold Front/Lead Wave Event:
A cold front will move through the region Wednesday and Wednesday night, associated with a storm system moving through Southern Canada. This frontal boundary will then become nearly stationary across the region and southern half of the state by Thursday morning. Precipitation in the form of rain will develop along and ahead of the cold front, across portions of Missouri, Iowa and Northwest Illinois and Wisconsin around midday Wednesday. This area of rain will expand as it further develops and pushes northeastward, spreading into other portions of Northern and Central Illinois Wednesday afternoon and evening, and eventually into Southern Illinois as well Wednesday night...Where isolated t'storms may be possible. As colder air filters in behind the slowing cold front pushing through the state, rain will transition to a mix of rain/freezing rain/sleet/snow across portions of Northern and Western Illinois late Wednesday evening into Wednesday night, and then continuing into Thursday morning. Minor snow/sleet/ice accumulation will be possible across portions of affected areas of Northern and Western Illinois, Wednesday night into Thursday morning.

Thursday Morning - Thursday Evening, Feb 17th ~ Main Winter Storm Event:
​As the main storm system moves through the region, an associated renewed push of precipitation will move across the state and region with the main impacts expected, Thursday morning through Thursday evening. This renewed push of precipitation, in the form of snow/sleet/ice, will move into Western Illinois early to mid Thursday morning. This area of precipitation will then spread across portions of Northern and all of Central Illinois late Thursday morning through mid Thursday afternoon, before ending Thursday evening. A transition zone will set up much of the day on Thursday across portions of Central Illinois. Across this zone, precipitation types will from south to north will range from freezing rain to sleet to snow. This transition zone will eventually change over to snow as precipitation ends mid Thursday afternoon into Thursday evening. North of this transition zone across affected areas of Northern and Central Illinois, most precipitation will fall as snow. Periods of moderate to heavy snow will be possible at times, with snowfall rates of 1"+ an hour likely at times. Additionally, a period of windy conditions is possible on Thursday. During this time wind gusts upwards of 20-35MPH will be possible, which will cause some blowing and drifting snow. 

​Below are the snowfall and ice forecasts for this winter storm.

​Severe T'Storm Risk/Heavy Rain/Flooding Aspect Forecast...
Thursday Morning - Thursday Evening, Feb 17th ~ Severe T'Storm Event:
​The main risk for an isolated severe t'storm risk will exist across far Southern Illinois, Thursday morning into Thursday afternoon. Areas of rain and isolated t'storms will be ongoing Thursday morning across Southern Illinois, in the vicinity of a nearly stationary frontal boundary in place. As the main storm system moves through the region, an arc of rain and t'storms will accompany the low pressure and cold front that sweeps across Southern Illinois, Thursday morning into Thursday afternoon. Ahead of this activity, an environment will be in place supportive of some severe t'storm risk with this activity. This environment will feature marginal instability of up to 500J/KG, dew points in the mid 50's to around 60, good shear, good forcing, and modest lapse rates of 5.0-7.0C. This environment will be supportive of upwards of an isolated severe t'storm risk (levels 1) across far Southern Illinois. Damaging winds, hail and an isolated tornado will be the severe weather threats.

Wednesday Afternoon - Thursday Evening, Feb 16-17th ~ Heavy Rain/Flooding Event:
Persistent periods of rainfall are expected across the southern half of the state Wednesday afternoon through Thursday afternoon, associated both with a frontal boundary becoming stationary across Southern Illinois and the main storm system moving through. During this period of time, periods of heavier rainfall will be possible. Widespread rainfall totals of 1-3" are expected across the southern half of the state during this period of time. Due to the combination of frost depth/frozen ground and the expected rainfall, some minor flooding will be possible for some areas.

Below are the severe t'storm and heavy rain/flooding forecast for this winter storm.

​Impacts...
-An axis of of snow/sleet accumulation of 2-5" across portions of Northern and Central Illinois, with locally higher amounts likely. Snowfall amounts will taper north and south of this main axis.
-Ice accumulations of a glaze (Up to 0.10") across much of the state, with an axis of scattered 0.10-0.25"+ ice accumulation across the heart of the state.
​-An isolated severe t'storm threat across Southern Illinois, Thursday morning through Thursday afternoon.
-Widespread heavy rainfall across the southern half of the state, with widespread rainfall totals of 1-3" expected. These rainfall totals could cause minor flooding potential for affected areas.
-Widespread travel impacts likely across much of the state, Wednesday night through Thursday evening.

JP

​​(2:00PM - 2/15/22) A winter storm is set to impact the region and state, Wednesday afternoon through Thursday evening. This winter storm is expected to produce a swath of accumulating snow/sleet/ice, heavy rainfall with minor flooding potential, and an isolated severe t'storm risk across the region and state during this time.

Summary...
Over the past several days model guidance has been honing in on the potential for a winter storm to affect the region and state, Wednesday through Thursday. While some model guidance continues to be in significant disagreement regarding this storm system, a large majority of model guidance has formed a consensus solution, which is what our current forecast is based off of. As stated, there still does continue to be some disagreement within model guidance at this time, so some changes to the forecast can be expected until full agreement on the situation is reached. Stay tuned to updates over the next several days regarding this winter storm.

​A cold front will move through the region Wednesday and Wednesday night, associated with a storm system moving through Southern Canada. This frontal boundary will then become nearly stationary across the region and southern half of the state, Thursday morning. Furthermore, a storm system will develop in the Southern Plains Wednesday night, and will then track through the Ohio Valley on Thursday, and eventually into the Northeast on Friday. This storm system will bring a renewed push of precipitation and main impacts of this period across the region and state, Thursday morning through Thursday evening.

​Wintry (Snow/Sleet/Ice) Aspect Forecast...
Wednesday Afternoon - Thursday Morning, Feb 16-17th ~ Cold Front/Lead Wave Event:
A cold front will move through the region Wednesday and Wednesday night, associated with a storm system moving through Southern Canada. This frontal boundary will then become nearly stationary across the region and southern half of the state by Thursday morning. Precipitation in the form of rain will develop along and ahead of the cold front, across portions of Missouri, Iowa and Northwest Illinois and Wisconsin around midday Wednesday. This area of rain will expand as it further develops and pushes northeastward, spreading into other portions of Northern and Central Illinois Wednesday afternoon and evening, and eventually into Southern Illinois as well Wednesday night...Where isolated t'storms may be possible. As colder air filters in behind the slowing cold front pushing through the state, rain will transition to a mix of rain/freezing rain/sleet/snow across portions of Northern and Western Illinois Wednesday night, and then continuing into Thursday morning. Minor snow/sleet/ice accumulation will be possible across portions of affected areas of Northern and Western Illinois, Wednesday night into Thursday morning.

Thursday Morning - Thursday Evening, Feb 17th ~ Main Winter Storm Event:
​As the main storm system moves through the region, an associated renewed push of precipitation will move across the state and region with the main impacts expected, Thursday morning through Thursday evening. This renewed push of precipitation, in the form of snow/sleet/ice, will move into Western Illinois by mid Thursday morning. This area of precipitation will then spread across portions of Northern and all of Central Illinois late Thursday morning through mid Thursday afternoon, before ending Thursday evening. A transition zone will set up much of the day on Thursday across portions of Central Illinois. Across this zone, precipitation types will from south to north will range from freezing rain to sleet to snow. This transition zone will eventually change over to snow as precipitation ends mid Thursday afternoon into Thursday evening. North of this transition zone across affected areas of Northern and Central Illinois, most precipitation will fall as snow. Periods of moderate to heavy snow will be possible at times, with snowfall rates of 1"+ an hour likely at times. Additionally, a period of windy conditions is possible on Thursday. During this time wind gusts upwards of 20-35MPH will be possible, which could cause some blowing and drifting snow. 

​Below are the snowfall and ice forecasts for this winter storm.

Severe T'Storm Risk/Heavy Rain/Flooding Aspect Forecast...
Thursday Morning - Thursday Evening, Feb 17th ~ Severe T'Storm Event:
​The main risk for an isolated severe t'storm risk will exist across far Southern Illinois, Thursday morning into Thursday afternoon. Areas of rain and isolated t'storms will be ongoing Thursday morning across Southern Illinois, in the vicinity of a nearly stationary frontal boundary in place. As the main storm system moves through the region, an arc of rain and t'storms will accompany the low pressure and cold front that sweeps across Southern Illinois, Thursday morning into Thursday afternoon. Ahead of this activity, an environment will be in place supportive of some severe t'storm risk with this activity. This environment will feature marginal instability of up to 500J/KG, dew points in the mid 50's to around 60, good shear, good forcing, and modest lapse rates of 5.0-7.0C. This environment will be supportive of upwards of an isolated severe t'storm risk (levels 1) across far Southern Illinois. Damaging winds, hail and an isolated tornado will be the severe weather threats.

Wednesday Afternoon - Thursday Evening, Feb 16-17th ~ Heavy Rain/Flooding Event:
Persistent periods of rainfall are expected across the southern half of the state Wednesday afternoon through Thursday afternoon, associated both with a frontal boundary becoming stationary across Southern Illinois and the main storm system moving through. During this period of time, periods of heavier rainfall will be possible. Widespread rainfall totals of 1-3" are expected across the southern half of the state during this period of time. Due to the combination of frost depth/hardened ground and the expected rainfall, some minor flooding will be possible for some areas.

Below are the severe t'storm and heavy rain/flooding forecast for this winter storm.

Impacts...
-An axis of of snow/sleet accumulation of 2-5" across portions of Northern and Central Illinois, with locally higher amounts likely. Snowfall amounts will taper north and south of this main axis.
-Ice accumulations of a glaze (Up to 0.10") across much of the state, with an axis of localized 0.10-0.25"+ ice accumulation across the heart of the state.
​-An isolated severe t'storm threat across Souther Illinois, Thursday morning through Thursday afternoon.
-Widespread heavy rainfall across the southern half of the state, with widespread rainfall totals of 1-3" expected. These rainfall totals could cause minor flooding potential for affected areas.
-Widespread travel impacts likely across much of the state, Wednesday night through Thursday evening.

JP

(12:30PM - 2/14/22) It is becoming increasingly likely that a winter storm will impact a large portion of the region and state this week. This winter storm will have the potential to produce an axis of accumulating snow, sleet and ice across portions of the state, Wednesday night through Thursday evening.

Summary...
Over the past several days model guidance has been honing in on the potential for a winter storm to affect the region and state, Wednesday through Thursday. While the potential for a winter storm to affect the state is likely, there is still uncertainty regarding track and strength of this system within model guidance...Which will affect the location of the snow, sleet and ice axis and associated snowfall, sleet and ice accumulations. Stay tuned for further updates over the next few days regarding this winter storm.

What we know...
-A winter storm will move through the region Wednesday through Thursday.
-An axis of accumulating snow, sleet and ice is expected across the state, with portions of Northern and Central Illinois favored at this time.

What we don't know...
-The exact track and strength of the storm system.
-The exact location of the snowfall, sleet and ice axis, and expected snowfall, sleet and ice amounts.

JP

(5:45PM - 2/5/22) A brief recap regarding the Tue-Thur, Feb 1-3rd major winter storm that produce a swath of significant accumulating snow/sleet/ice across the region and state during this time.

Summary...
A cold front moved across the region on Tuesday, associated with a storm system moving through Southern Canada. This frontal boundary became nearly stationary across portions of the region and Southern Illinois Tuesday night into Wednesday. With ample advection from the south over-topping this frontal boundary, a widespread overrunning precipitation event occurred across the region and state, midday Tuesday through Wednesday evening. Furthermore, a storm system developed in the Southern Plains on Wednesday, and then tracked through the Tennessee Valley on Thursday, and eventually into the Mid-Atlantic region on Friday. This storm system brought a renewed push of precipitation across the region and state, Wednesday night through Thursday night.

Summary...
Tuesday Midday - Wednesday Evening, Feb 1-2nd ~ Overrunning Precipitation Event:
A cold front moved through the region on Tuesday, associated with a storm system moving through Southern Canada. This frontal boundary slowed and became nearly stationary across the region and southern half of the state Tuesday night into today. With ample advection of mild/moist air from the south over-topping this frontal boundary, a widespread overrunning precipitation event occurred across the region and state, Tuesday morning through Wednesday evening. Precipitation, in the form of rain, developed and spread across the state Tuesday morning into Tuesday evening. As colder air filtered in on behind the slowing cold front pushing through the state, rain transitioned to a mix and snow across affected areas of Northern and Central Illinois Tuesday evening into Tuesday night. Snow then continued in varying intensity across a large portion of Northern and all of Central Illinois, from transition time through Wednesday afternoon and evening. Periods of moderate to heavy snow occurred at times, with more lull-like periods of lighter snows likely as well. Snowfall rates upwards of 1"+ an hour also occurred at times in the heavier periods of snow, especially Tuesday night through Wednesday morning. Across southern portions of Central Illinois, this is where the overall transition zone set up with mixed precipitation set up Tuesday night into Wednesday morning. Across this zone, precipitation types from south to north ranged from freezing rain to sleet to snow. This transition zone shifted southward Wednesday morning across Southern Illinois, and will eventually stalled out across Southern Illinois during the day on Wednesday.

Wednesday Night - Thursday Evening, Feb 2-3rd ~ Main Storm System:
As the overrunning precipitation continued across the state into Wednesday evening, the main storm system will also move into the region. A renewed push of precipitation moved across the state and region associated with the main storm system, Wednesday night through Thursday evening. This renewed push of precipitation, in the form of snow, moved into Southwestern Illinois Wednesday night. This area of snow then spread across portions of Central and Southern Illinois, from  Wednesday night through Thursday afternoon, before ending by Thursday evening. Periods of moderate to heavy snow occurred at times, with snowfall rates of 1-2" an hour having also occurred at times. Additionally, a period of windy conditions occurred Wednesday morning through Thursday afternoon. During this time wind gusts upwards of 25-40MPH occurred across portions of Central and Southern Illinois, which caused blowing and drifting snow. Further south across Southern Illinois, the transition zone of mixed precipitation was in place Wednesday night through Thursday morning. Across this zone in Southern Illinois, precipitation types from south to north will range from freezing rain to sleet to snow. This transition zone eventually changed over to snow during the day on Thursday, before ending.

In additional to the synoptic aspect to this winter storm period, conditions were favorable for a bit of lake enhanced and lake effect snow across portions of Northeast Illinois, Wednesday night through Thursday evening. This enhanced snowfall totals a bit for portions of Northeast Illinois near Lake Michigan.

Wrap Up...
-An axis of of significant snowfall totals occurred across the heart of the state, with snowfall totals upwards of 8-15" in the main corridor, with locally higher amounts. Snowfall amounts quickly tapered north and south of this main axis, across Northern and Southern Illinois.
-An axis of significant ice accumulations of 0.10-0.50" occurred across Southern Illinois.
-Windy conditions on Wednesday and Thursday caused blowing and drifting snow across the heart of the state.
-Significant and widespread travel impacts occurred across much of the state, especially across the heart of the state

​​Below are map representations of the final forecasts and observed totals of snowfall and ice across the state and adjacent areas. 

JP

(10:45AM - 2/2/22) A major winter storm will continue to impact region and state, through Thursday night. This winter storm will produce a swath of significant accumulating snow/sleet/ice across the region and state during this time.
​
Summary...
A winter storm continues to unfold across the region, and has been impacting the state since midday Tuesday. Last night into this morning the first part of this winter storm brought a widespread accumulating snowfall occurred across Northern and Central Illinois, with mixed precipitation across portions of Central Illinois as well. This first part of this winter storm will continue to affect the state through this evening. The second part of this winter storm will affect the state, tonight through Thursday evening. Regarding the second part to this winter storm, model guidance continues to be in fairly good agreement in showing a consensus solution. However, this solution has trended a bit south over the past 12-18 hours. Thus, this additional update has been warranted to update forecast information.

​A cold front moved across the region on Tuesday, associated with a storm system moving through Southern Canada. This frontal boundary became nearly stationary across portions of the region and Southern Illinois Tuesday night into Wednesday. With ample advection from the south over-topping this frontal boundary, a widespread overrunning precipitation event has been occurring across region and state, Tuesday morning through this evening. Furthermore, a storm system will develop in the Southern Plains today, and will then track through the Tennessee Valley on Thursday, and eventually into the Mid-Atlantic region on Friday. This storm system will bring a renewed push of precipitation across the region and state, tonight through Thursday night.

Forecast...
This Morning - This Evening, Feb 2nd ~ Overrunning Precipitation Event:
A cold front moved through the region on Tuesday, associated with a storm system moving through Southern Canada. This frontal boundary slowed and became nearly stationary across the region and southern half of the state Tuesday night into today. With ample advection of mild/moist air from the south over-topping this frontal boundary, a widespread overrunning precipitation event has been occurring across the region and state, Tuesday morning through this morning. Precipitation, in the form of rain, developed and spread across the state Tuesday morning into Tuesday evening. As colder air filtered in on behind the slowing cold front pushing through the state, rain transitioned to a mix and snow across affected areas of Northern and Central Illinois Tuesday evening into Tuesday night. Snow will continue in varying intensity across a large portion of Northern and all of Central Illinois, through this afternoon and evening. Periods of moderate to heavy snow will be possible at times, with more lull-like periods of lighter snows likely as well. Snowfall rates upwards of 1" an hour will be likely at times in the heavier periods of snow, especially through this afternoon. Across southern portions of Central Illinois, this is where the overall transition zone set up with mixed precipitation set up Tuesday night into this morning Across this zone, precipitation types from south to north ranged from freezing rain to sleet to snow. This transition zone has been shifting southward this morning across Southern Illinois, and will eventually stall out across Southern Illinois today.

Tonight - Thursday Evening, Feb 2-3rd ~ Main Storm System:
As the overrunning precipitation continues across the state into this evening, the main storm system will also move into the region. A renewed push of precipitation will move across the state and region associated with the main storm system, tonight through Thursday evening. This renewed push of precipitation, in the form of snow, will move into Southwestern Illinois tonight. This area of snow will then spread across portions of Central and Southern Illinois, from tonight through Thursday afternoon, before ending by Thursday evening. Periods of moderate to heavy snow will be possible at times, with snowfall rates of 1-2" an hour likely at times. Additionally, a period of windy conditions is possible Wednesday night through Thursday evening. During this time wind gusts upwards of 25-40MPH will be possible, which will cause blowing and drifting snow. Further south across Southern Illinois, the transition zone of mixed precipitation will be in place toight Across this zone in Southern Illinois, precipitation types from south to north will range from freezing rain to sleet to snow. This transition zone will eventually change over to snow Thursday morning, continuing into Thursday evening before ending.

In additional to the synoptic aspect to this winter storm period, conditions will be favorable for lake enhanced and lake effect snow across portions of Northeast Illinois, this evening through Thursday night. This will likely enhance snowfall totals for portions of the Chicago area near Lake Michigan.

​Impacts...
-An axis of of significant snowfall totals across the heart of the state, with upwards of 7-15" in the main corridor, with locally higher totals possible. Snowfall amounts will quickly taper north and south of this main axis, across Northern and Southern Illinois.
-An axis of significant ice accumulations of 0.10-0.50"+ across Southern Illinois.
-Significant and widespread travel impacts likely across much of the state, through Thursday evening.
​-This is a long duration winter storm, with impacts across the state spread out over a two day period.

​Below are the snowfall and ice forecasts for this winter storm.

JP