(11:45AM - 3/16/21) A storm system will move through the region Wednesday into Thursday, bringing a low end severe t'storm threat to the southern half of the state and windy conditions to Northern and Central Illinois.

Summary...
A storm system will move from the Plains on Wednesday, into the Ohio Valley on Thursday. The northern side of a larger and more significant severe t'storm risk to the south will reach into the southern half of the state, with a low end severe t'storm threat being possible Wednesday afternoon through Thursday morning. Additionally, a period of windy conditions are expected across Northern and Central Illinois, Wednesday evening through Thursday evening.

​Forecast...
Scattered showers and t'storms will spread across Southern Illinois Wednesday morning into Wednesday afternoon, as a warm front lifts towards and into Southern Illinois. In the wake of this early activity and with the warm front in the vicinity, a marginal environment will develop. This marginal environment will feature low instability, modest moisture and great shear. Scattered showers and t'storms that develop along a cold front across Missouri and Arkansas during the afternoon, will spread across the southern half of the state Wednesday evening through early Thursday morning. Given the aforementioned marginal environment in place, a low end severe t'storm threat will exist with this activity, with a few severe t'storms being possible. Hail, damaging winds and an isolated tornado will be possible with any severe t'storm.

In addition the the severe t'storm potential, windy conditions are expected Wednesday evening through Thursday evening across Northern and Central Illinois. High winds aloft, characterized by a low level jet of 40-60KT, will be in place. The amount of mixing will be limited, thus preventing even higher winds. However, expected mixing depth will support northeasterly wind gusts of 25-45MPH across Northern and Central Illinois, Wednesday evening through Thursday evening.

Below is the severe t'storm and wind forecasts for this event.

JP

(10:00PM - 3/15/21) A storm system will move through the region Wednesday into Thursday, bringing a low end severe t'storm threat to the southern half of the state.

Summary...
A storm system will move from the Plains on Wednesday, into the Ohio Valley on Thursday. The northern side of a larger and more significant severe t'storm risk to the south, will reach into the southern half of the state, with a low end severe t'storm threat being possible Wednesday afternoon through Thursday morning.

Forecast...
Scattered showers and t'storms will spread across Southern Illinois Wednesday morning into Wednesday afternoon, as a warm front lifts towards and into Southern Illinois. In the wake of this early activity and with the warm front in the vicinity, a marginal environment will develop. This marginal environment will feature low instability, modest moisture and great shear. Scattered showers and t'storms that develop along a cold front across Missouri and Arkansas during the afternoon, will spread across the southern half of the state Wednesday evening through early Thursday morning. Given the aforementioned marginal environment in place, a low end severe t'storm threat will exist with this activity, with a few severe t'storms being possible. Hail, damaging winds and an isolated tornado will be possible with any severe t'storm.

Below is the severe t'storm forecast for this event.

JP

(10:30AM - 3/15/21) A storm system will be moving through the region through Tuesday, bringing a snow/sleet/ice event to Northern and portions of Central Illinois and windy conditions to much of the state.

Summary...
A storm system will move from the Plains today and into the Ohio Valley by Tuesday morning. This storm system will bring a period of precipitation to the state through tonight, and windy conditions to the state through later this afternoon. Model guidance and real time observations suggest the forecast is on track for the most part.

Forecast...
Northern Illinois...
An area of precipitation has been spreading across Northern Illinois this morning. Precipitation has been a mix of snow/sleet/freezing rain, with generally all snow across far Northwest Illinois. This area of precipitation will continue to spread across Northern Illinois through this evening, continuing as a mix for many areas, with the exception being far Northwest and North-Central Illinois where all snow is expected. Periods of moderate to heavy snow will be possible at times across far Northwest and North-Central Illinois. Precipitation will fully come to an end across Northern Illinois tonight.

Central Illinois...
Further south across portions of Central and Eastern Illinois, enough evaporation cooling has been occurring to allow precipitation to fall as sleet/freezing rain for many areas East-Central Illinois. This precipitation will end by mid-afternoon.

In addition the the snow potential, windy conditions are expected through this evening. High winds aloft, characterized by a low level jet of 45-65KT, will be in place. The amount of mixing will be limited, thus preventing even higher winds. However, expected mixing depth will support easterly wind gusts of 25-45MPH across the state, through this evening.

What's expected...
An axis of snowfall totals of 1-3" is expected across Northern Illinois, with higher accumulation expected across Northwest Illinois where upwards of 2-5" or 4-7" is expected. Across other portions of Northern Illinois, generally from I-88 on south, minor sleet and ice accumulations are expected, in addition to tapering snowfall amounts.

​Below is the snow/sleet, ice and wind forecasts for this event.

JP

(10:45PM - 3/14/21) A storm system will be moving through the region through Tuesday, bringing a snow event to Northern Illinois and windy conditions to the state.

Summary...
A storm system will move from the Plains tonight and into the Ohio Valley by Tuesday morning. This storm system will bring a period of precipitation to the state tonight through Monday night, and windy conditions to the state through Monday afternoon. Model guidance continues to be in some disagreement regarding thermal profiles and snowfall amounts across Northern Illinois. However, all other aspects of the storm system have high agreement.

Forecast...
An area of precipitation will first enter Northwest Illinois late tonight/very early Monday morning. Precipitation will likely start as rain, before changing over to snow. This precipitation will then spread across the remainder of Northern Illinois Monday morning, also starting as rain or a mix, before changing over to snow. A period of snow is then expected across a good portion of Northern Illinois along/north of I-80, Monday morning through Monday afternoon. Snow will be of varying intensity during this time. This will be a heavier/wetter, with marginal temperatures expected, which will lead to some melting as the event is ongoing. Snow will then end Monday evening, potentially as a mix in some areas. Further south, along/south of I-80, after beginning as rain earlier Monday morning...Precipitation will likely be a mix of rain/freezing rain/sleet/snow for much of the event.

In addition the the snow potential, windy conditions are expected tonight through Monday afternoon. High winds aloft, characterized by a low level jet of 45-65KT, will be in place. The amount of mixing will be limited, thus preventing even higher winds. However, expected mixing depth will support easterly wind gusts of 25-45MPH across the state, tonight through Monday afternoon.

What's expected...
An axis of snowfall totals of 2-5" are expected norther of I-80 in Northwest and North-Central Illinois, with locally higher amounts possible. Snowfall amounts of 1-3" are expected in Northeast Illinois. Snowfall amounts will taper near and south of I-80. Near and south of I-80, there will also be minor sleet of a few tenths and freezing rain accumulation up to a glaze possible.

​Below is the snow and wind forecasts for this event.

JP

(11:45AM - 3/14/21) A storm system is expected to move through the region tday through Tuesday, bringing an accumulating snowfall to portions of Northern Illinois and windy conditions to the state.

Summary...
A storm system will move from the Plains tonight and into the Ohio Valley by Tuesday morning. This storm system will bring a period of precipitation to the state tonight through Monday night, and windy conditions to the state this afternoon through Monday afternoon. Model guidance continues to be in some disagreement regarding placement of the snowfall axis across Northern Illinois, and snowfall amounts. However, all other aspects of the storms system has high agreement.

Forecast...
An area of precipitation will first enter Northwest Illinois late tonight/very early Monday morning. Precipitation will likely start as rain, before changing over to snow. This precipitation will then spread across the remainder of Northern Illinois Monday morning, also starting as rain or a mix, before changing over to snow. A period of snow is then expected across a good portion of Northern Illinois along/north of I-80, Monday morning through Monday afternoon. Snow will be of varying intensity during this time. This will be a heavier/wetter, with marginal temperatures expected, which will lead to some melting as the event is ongoing. Snow will then end Monday evening, potentially as a mix in some areas. Further south, along/south of I-80, after beginning as rain earlier Monday morning...Precipitation will likely be a mix of rain/freezing rain/sleet/snow for much of the event.

In addition the the snow potential, windy conditions are expected this afternoon through Monday afternoon. High winds aloft, characterized by a low level jet of 45-65KT, will be in place. The amount of mixing is questionable and will likely be limited, thus preventing even higher winds. However, expected mixing depth will support easterly wind gusts of 25-45MPH across the state, this afternoon through Monday afternoon.

​What's expected...
Snowfall totals of 1-3" are expected along/north of I-80 across Northern Illinois, with amounts tapering to the south where minor sleet and ice accumulation is possible along/south of I-80 in Northern Illinois. Higher snowfall amounts of 2-5" are possible across Northwest Illinois.

​Below is the snow and wind forecasts for this event.

JP

(11:45PM - 3/13/21) A storm system is expected to move through the region on Monday, bringing an accumulating snowfall to portions of Northern Illinois.

Summary...
A storm system will move from the Plains on Sunday night and into the Ohio Valley by Tuesday morning. This storm system will bring a period of precipitation to the state on Monday, and windy conditions to the state Sunday afternoon through Monday afternoon. Model guidance continues to be in some disagreement regarding placement of the snowfall axis across Northern Illinois, and snowfall amounts. However, all other aspects of the storms system has high agreement.

Forecast...
An area of precipitation will first enter Northwest Illinois very early Monday morning. Precipitation will likely start as rain or a mix, before changing over to snow. This precipitation will then spread across the remainder of Northern Illinois Monday morning, also starting as rain or a mix, before changing over to snow. A period of snow is then expected across a good portion of Northern Illinois, Monday morning through Monday afternoon. Snow will be of varying intensity during this time. This will be a heavier/wetter, with marginal temperatures expected, which will lead to some melting as the event is ongoing. Snow will then end Monday evening, potentially as a mix in some areas. Further south across Central and Southern Illinois, this will likely be an entirely rain event.

In addition the the snow potential, windy conditions are expected Sunday afternoon through Monday afternoon. High winds aloft, characterized by a low level jet of 45-65KT, will be in place. The amount of mixing is questionable and will likely be limited, thus preventing even higher winds.However, expected mixing depth will support easterly wind gusts of 25-45MPH across the state, Sunday afternoon through Monday afternoon.

What's expected...
Snowfall totals of 1-3" are expected along/north of I-80 across Northern Illinois, with amounts tapering to the south. Higher snowfall amounts of 2-5" are possible across Northwest Illinois.

​Below is the snow and wind forecasts for this event.

JP

(11:15AM - 3/13/21) A storm system is expected to move through the region on Monday, bringing an accumulating snowfall to portions of Northern Illinois.

Summary...
A storm system will move from the Plains on Sunday night and into the Ohio Valley by Tuesday morning. This storm system will bring a period of precipitation to the state on Monday, and windy conditions to the state Sunday afternoon through Monday afternoon. Model guidance has been showing the potential for accumulating snow across Northern Illinois for the past several days. However, there has been and continues to be some disagreement regarding placement of the snowfall axis and snowfall amounts.

Forecast...
An area of precipitation will first enter Northwest Illinois very early Monday morning. Precipitation will likely start as rain or a mix, before changing over to snow. This precipitation will then spread across the remainder of Northern Illinois Monday morning, also starting as rain or a mix, before changing over to snow. A period of snow is then expected across a good portion of Northern Illinois, Monday morning through Monday afternoon. Snow will be of varying intensity during this time. This will be a heavier/wetter, with marginal temperatures expected, which will lead to some melting as the event is ongoing. Snow will then end Monday evening, potentially as a mix in some areas. Further south across Central and Southern Illinois, this will likely be an entirely rain event.

In addition the the snow potential, windy conditions are expected Sunday afternoon through Monday afternoon. High winds aloft, characterized by a low level jet of 45-65KT, will be in place. The amount of mixing is questionable and will likely be limited, thus preventing even higher winds.However, expected mixing depth will support easterly wind gusts of 25-45MPH across the state, Sunday afternoon through Monday afternoon.

​What's expected...
Snowfall totals of 1-3" are expected along/north of I-80 across Northern Illinois, with amounts tapering to the south. Higher snowfall amounts of 2-5" are possible across Northwest Illinois. 

​Below is the snow and wind forecasts for this event.

JP

(2:30PM - 3/11/21) A disturbance moving through the region will bring a low end severe t'storm threat to Southern Illinois, this afternoon and evening.

Forecast...
A disturbance moving through the region will bring a low end/minor severe t'storm threat to portions of Southern Illinois, this afternoon and evening. A large area of rain and t'storms has been spreading across Southern Illinois this afternoon, generally along and north of a frontal boundary pushing southward across Southern Illinois. South of this boundary a marginal environment exists... Featuring good shear, low instability and good moisture for the time of year. While this environment is marginal, it is enough to support an isolated severe t'storm threat. As activity continues to push eastward across Southern Illinois this afternoon and evening, along and ahead of the frontal boundary, an isolated severe t'storm threat will exist. Damaging winds and hail will be the main threats.

​Below is the severe t'storm forecast for this event.

JP

(11:30AM - 3/10/21) A storm system moving through the region today into Thursday will bring a period of high winds to the state, from this morning through Thursday morning.

​​Forecast...
A storm system moving through the region today into Thursday will bring a period of high winds to the state, this morning through Thursday morning. High winds aloft, characterized by a low level jet of 50-70KT, will be in place. With ample sun/clearing expected across the state today, ample mixing is expected. This will help support wind gusts of 30-45MPH across the southern half of the state, and 35-55MPH wind gusts across the northern half of the state...where locally higher wind gusts in excess of 55MPH are possible. Winds will be southerly for the duration of the event, which will make for hazardous travel for high profile vehicles on west-east roads. Additionally, for areas impacted by the strongest winds, isolated minor tree damage and isolated power outages are possible. Winds will diminish overnight tonight and into Thursday morning from north to south across the state, as a cold front pushes through.

​Below is the high wind forecast for this event.

JP

(8:00PM - 3/9/21) A storm system moving through the region on Wednesday and Thursday will bring a period of high winds to the state, Wednesday morning through Thursday morning.

​​Summary...
A storm system moving through the region on Wednesday and Thursday will bring a period of high winds to the state, Wednesday morning through Thursday morning. High winds aloft, characterized by a low level jet of 50-70KT, will be in place. Mixing depth is in question, however it is expected to be deep enough to support widespread southerly 30-45MPH wind gusts. Locally higher wind gusts of 45-50MPH are possible if deeper mixing can occur.

​Below is the high wind forecast for this event.

JP