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(9:00PM - 11/25/19) The same storm system that will bring high winds to the state on Tuesday and Wednesday, will also bring a low end threat for strong and severe t'storms to the state.
A broken line of showers and t'storms is expected to develop along a cold front, across portions of Iowa and Missouri, late Tuesday afternoon and evening. Ahead of this activity an environment will be in place featuring 50-60 degree dew points and <1,000 J/KG CAPE. On the other end of the spectrum, shear will be on the high end of the scale. In other words, this is a low moisture/instability and high shear setup. As the broken line of showers and t'storms races northeastward across the state Tuesday night, isolated strong to severe t'storms will be possible. By no means does this look like a significant or widespread severe weather event. However, given the time of year and holiday travel will be underway for some, it is noteworthy. Damaging/high winds will be the greatest threat with this activity. High winds are already expected outside of showers and t'storms, but this activity could enhance the wind potential. Additionally, an isolated tornado cannot be ruled out given there will be some instability in place, coupled with the strong shear. Below is the TAM severe t'storm forecast for this event. 
JP
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(7:30PM - 11/25/19) A storm system is expected to move across the region Tuesday and Wednesday, which will bring an extended period of high winds to the state.
The high winds during this period will be a product of a quickly organizing and strengthening storm system, and associated strong jet streak aloft. 850mb winds aloft of 40-60kts is likely, with mixing potentially up near that level at times, which correlates to the expected high winds at the surface.
Winds will increase across the state late Tuesday afternoon and into Tuesday night, as the storm system enters the region. Wind gusts will increase to 20-40mph across the state during this time. Overnight Tuesday and into Wednesday afternoon, winds will increase even more. This will occur just ahead of a passing cold front, and on the backside of the storm system. Wind gusts during this time will be in the 45-60mph range. Isolated higher wind gusts in excess of 60mph will be possible as well. Winds will gradually diminish later Wednesday afternoon and evening across the state.
Due to the expected wind gusts and prolonged nature of higher wind gusts, some tree damage and power outages will be possible across the state. Below is the TAM high wind forecast for this event. 
JP
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(11:45AM - 11/25/19) A storm system is expected to move across the region Tuesday and Wednesday, and expected to bring high winds to the state.
Winds will increase across the state late Tuesday afternoon and into Tuesday night, as a storm system enters the region. Wind gusts will increase to 20-40mph across the state during this time. Overnight Tuesday and into Wednesday morning, wind gusts of 35-50mph will be likely across the state, along and ahead of a cold front sweeping across the state. Higher gusts of 50-55mph will be possible, especially in and around expected isolated to scattered thunderstorms. The rest of the day Wednesday will feature wind gusts of 30-50mph across the state, on the backside of the storm system. Winds will gradually diminish later Wednesday afternoon and evening across the state. Below is the TAM high wind forecast for this event. 
JP
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(4:00PM - 11/22/19) A storm system is expected to move across the region tonight into Saturday, which will affect portions of the state during this time.
As was outlined in our original post from Wednesday night, "Potential Weekend Accumulating Snow?", model guidance was showing a storm system potentially affecting the state during the time-frame of tonight into Saturday. Model guidance was significantly struggling with this system and the overall pattern, in a complex setup. Two scenarios were outlined in the original post... #1... The southern stream disturbance is slower at ejecting out into the Plains, with a northern stream disturbance digging into the Northern U.S. This would allow for partial phasing to occur, thus a more pronounced storm system with the potential for at least a couple inches of snow within a swath across the heart of the state. #2... The southern stream disturbance is faster and ejecting out, misses a partial phase with the northern stream disturbance, and is instead sheared out. This would lead to a very weak storm system, with little to no chance for snow across the state.  GFS model depiction for Saturday morning.
At the time of the original post, model guidance was fairly split between both scenarios, but slightly favored scenario #1...which resulted in the need for a post outlining the potential, especially given it was only 2-3 days away. Since that time, model guidance continued to struggle for a while, before finally coming into agreement on the original outlined scenario #2. With all of that said, a storm system is still expected to move across the region tonight into Saturday. Rain showers will be possible across Central and Southern Illinois during this time. With some cold air in place, some snow showers will be possible across Central Illinois and vicinity. Little to no snow accumulation is expected. This will likely be the last update regarding this storm system.
JP
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(9:30PM - 11/20/19) A storm system is expected to move across the region Friday into Saturday, which potentially could bring accumulating snow to portions of the state.
Over the past several days model guidance has been hinting at the potential for accumulating snow across portions of the state, Friday night into Saturday afternoon, as a storm system moves through the region. However, there has been a high amount of disagreement regarding this potential event...Ranging from no storm system at all on some model guidance, to a pronounced storm system with several inches of snow on other model guidance. The main issue giving model guidance a fuss is a complex scenario in place, which will feature a southern stream disturbance across the Inter-mountain West and a potential partial phase or shearing, with a northern stream disturbance dropping in from Canada. How these two disturbances evolve and interact will determine how the storm system evolves for the region.
Two scenarios are in play at this time...
#1... The southern stream disturbance is slower at ejecting out into the Plains, with a northern stream disturbance digging into the Northern U.S. This would allow for partial phasing to occur, thus a more pronounced storm system with the potential for at least a couple inches of snow within a swath across the heart of the state. #2... The southern stream disturbance is faster and ejecting out, misses a partial phase with the northern stream disturbance, and is instead sheared out. This would lead to a very weak storm system, with little to no chance for snow across the state. More recently, model guidance has been trending towards the above mentioned scenario #1. Further updates will be provided over the coming days. Note: On the below map, the area of "accumulation possible" does not mean you will see snowfall accumulation. This is merely a depiction of where the range of model guidance has would suggest accumulating snow would be possible, should it occur. 
JP
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(4:00PM - 11/13/19) A weak and fast moving disturbance moving through the region will bring the chance for a bit of snow to portions of the state, through tonight.
An area of snow will be pushing into portions of Northwest Illinois shortly. This area of snow will spread across portions of Northern Illinois during the evening and into tonight, before slowly ending from west to east overnight. This snow will be associated with a weak and fast moving disturbance pushing through the region. This will be a nuisance event, with just minor snow accumulation of a dusting up to 1" expected across portions of Northern Illinois...with locally amounts in excess of 1" being possible for isolated areas. Below is the TAM snowfall forecast for this event. 
JP
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(6:00PM - 11/13/19) Following the Veterans Day snowstorm, very cold temperatures for early November settled in across the region. This period featured record breaking and historic cold for this early in the season/early November. A brief recap...
Monday night/Tuesday morning low temperatures ranged from just below zero to the single digits across Northern and Central Illinois, to the single digits to teens across Southern Illinois. On Tuesday, high temps remained in the teens across much of the state, the only exception be portions of far Southern Illinois that made it into the 20's. Tuesday night/Wednesday morning low temps ranged from just below zero to the single digits across much of the state, the only exception be portions of far Southern Illinois that stayed in the teens.
While this type of cold was nothing out of the ordinary by mid-winter standards, it was very noteworthy for the time of year. As was mentioned above, this was record breaking and historic cold for this early in the season/early November. Daily record low max and low temps were broken across the state during this period. Additionally, these were some of the coldest temps that have occurred this early in a season before for many areas. Below are a list of cities and new/old records...Some of these records were smashed.
New records in bold/italics. .....Chicago..... Nov 11th Record Low... New: 13 (2019)/Old: 15 (1950) Nov 12th Record Low Max... New: 17 (2019)/Old: 28 (1995) Nov 12th Record Low... New: 7 (2019)/Old: 8 (1986) .....Rockford..... Nov 11th Record Low: 10 (1926) 11 Nov 12th Record Low Max... New: 16 (2019)/Old: 27 (1940) Nov 12th Record Low... New: 3 (2019)/Old: 7 (1986) .....Dubuque..... Nov 11th Record Low: 6 (1986) 7 Nov 12th Record Low Max... New: 13 (2019)/Old: 16 (1911) Nov 12th Record Low... New: -5 (2019)/Old: 6 (1986) .....Moline..... Nov 11th Record Low... New: 11 (2019)/Old: 12 (1950) Nov 12th Record Low Max... New: 19 (2019)/Old: 20 (1911) Nov 12th Record Low... New: 6 (2019)/Old: 8 (1986) .....Galesburg..... Nov 11th Record Low... New: 10 (2019)/Old: 13 (2008) Nov 12th Record Low Max... New: 17 (2019)Old: 24 (1940) Nov 12th Record Low... New: 0 (2019)/Old: 8 (1986) .....Peoria..... Nov 11th Record Low... Tie: 13 (2019/1995) Nov 12th Record Low Max... Tie: 18 (2019/1911) Nov 12th Record Low... New: 5 (2019)/Old: 9 (1986)
.....Springfield.....
Nov 11th Record Low... Tie: 13 (2019/1995) Nov 12th Record Low Max... New: 18 (2019)/Old: 19 (1911) Nov 12th Record Low... New: 5 (2019)/Old: 12 (1986/1995) .....Lincoln..... Nov 11th Record Low... Tie: 13 (2019/1913) Nov 12th Record Low Max... New: 18 (2019)/Old: 27 (1995) Nov 12th Record Low... New: 4 (2019)/Old: 10 (1919) .....Champaign..... Nov 11th Record Low... New: 11 (2019)/Old: 16 (1995/1950/1913) Nov 12th Record Low Max... New: 16 (2019)/Old: 27 (1920) Nov 12th Record Low... New: -1 (2019)/Old: 9 (1911) Nov 13th Record Low... New: 3 (2019)/Old: 7 (1986) .....Quincy..... Nov 11th Record Low... Tie: 12 (2019/1950) Nov 12th Record Low Max... New: 18 (2019)/Old: 28 (2014) Nov 12th Record Low... New: 5 (2019)/Old: 10 (1986) .....St. Louis..... Nov 11th Record Low... New: 16 (2019)/Old: 18 (1976/1950/1911) Nov 12th Record Low Max: 20 (1911) 21 Nov 12th Record Low... New: 11 (2019)/Old: 12 (1911) .....Paducah..... Nov 11th Record Low: 18 (1960) 24 Nov 12th Record Low Max... New: 26 (2019)/Old: 36 (1911) Nov 12th Record Low... New: 12 (2019)/Old: 21 (1995/1986/1976) Nov 13th Record Low... Tie: 10 (2019/1986) 
JP
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After what was a busy end of October and first ten days of November with several record setting snows across the state along with several days of record temperatures, we will enter a stretch of fairly quiet and boring weather across the Midwest, including here in Illinois. I dig into some details below....
After a weak weather disturbance passes through the Midwest and far northern Illinois with a shot of some light snow, broad high pressure will slowly build into our region from the central plains. This will lead to a several day stretch of quiet and dry weather across the Midwest as you can see below, with any precipitation avoiding our area.
With continued northwest flow aloft allowing for bouts of colder temperatures into the Midwest, surface temperatures will remain well below normal, especially across the northern half of the state. Below is forecast daytime highs across the state for tomorrow.
With some more sunshine expected on Friday thanks to the area of high pressure over the region, temperatures will be a bit warmer with more widespread 40's expected. The cool spots will be across northern Illinois where the deepest snow pack currently resides, aiding in keeping temperatures cooler.
Beyond Saturday, daytime highs will continue to be below normal Sunday and Monday ranging from the upper 30's to upper 40's from north to south across the State. Regarding any precipitation chances, numerical model guidance continue to try to bring a weak front into the region from the west with chances for some precipitation but as of now, much of Illinois will remain on the dry side outside of a spotty shower.
(6:00AM - 11/13/19) A weak and fast moving disturbance moving through the region will bring the chance for a bit of snow to portions of the state, this afternoon into tonight.
A period of light snow will be possible across portions of Northern Illinois, late this afternoon into tonight. This snow will be associated with a weak and fast moving disturbance pushing through the region. Overnight model guidance has shifted slightly south with this “event”, thus have expanded snow potential a bit with this update. This will be a nuisance event, with just minor snow accumulation of a dusting is possible across portions of Northern Illinois. Below is the TAM snowfall forecast for this event. 
JP
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