Mild Monday But Wintry By The Weekend
60s To Start Week Then Dramatic Drop
Our first day since daylight savings time ended was delightful. Sunday was the warmest day in nearly three weeks. Yesterday's high soared to 65° or 13° above average. Today could be a degree or two warmer with highs more like we expect in early October rather than early November. Enjoy this unseasonably warm start to the week because it will be wintry here by the weekend. Highs will fall back into the 40s and some snowflakes could fly for the first time this fall. Watch for gusty winds to arrive with a storm system on Thursday and continue through Friday.
The HRRR model has highs today climbing into the middle 60s for the second straight day. Some sunshine and a southwest wind will push our highs to 10° to 15° above average.
A cold front comes through tonight and will help knock our highs back down closer to average on Tuesday. The GFS Model has our highs falling back into the middle 50s on Tuesday.
By the end of the week our highs fall back into the 40s and could stay there for several days in a row. The GFS Model has temperatures Friday afternoon in the lower to middle 40s. Strong winds will make it feel even colder. Wind chills should drop into the 30s for most of the day.
The cold keeps coming through the weekend. The GFS model temperature anomaly forecast for Saturday afternoon shows temperatures here between 6° to 10° below average. That means highs Saturday in the lower to middle 40s.
So after 60s for highs today then a cold front shifts our winds tonight to the north and eventually the northeast. That sets us up for a cloudier and cooler Tuesday. There is a chance for some sprinkles or light rain beginning late Tuesday morning into Tuesday night.
So Long 60s After Today
Today will be the third day in a row with above average temperatures and the second day in a row with highs in the 60s. The National Blend Of Models has our highs falling back into the 50s Tuesday through Thursday. It then has a more dramatic drop in temperatures later this week with highs falling into the 40s by Friday and staying there into at least the middle of next week.
The longer range temperature outlooks keeps the relatively colder pattern coming through the third week of this month. The 6-10 day outlook still has us favored for below average temperatures overall from November 13th through November 17th. The longer range 8-14 day forecast favors us for colder than average temperatures overall from November 15th through November 21st. Average highs for this period are in the middle 40s to near 50°.
The even longer term 35 day temperature anomaly forecast has us bouncing back a bit above average overall when averaged out from now to nearly the middle of December. Northern Illinois is again outlooked to be between 1° to 3° below average. This forecast covers the period from November 6th through December 11th. The Global Ensemble Forecast System (GEFS) is a weather forecast model made up of 21 separate forecasts, or ensemble members The model tries to give an idea of the amount of uncertainty in a forecast by running an ensemble of multiple forecasts which are each tweaked a bit with their initial conditions.
Will Flakes Fly Soon?
November's precipitation is now running .62" below average. On average by this point of fall we have about a third of an inch of snow. We have yet to see our first flakes of snow but that could happen by the end of this week.
The most recent US Drought Monitor analysis was released last Thursday. Here is a recap:
After three reports in a row with good news for Illinois the latest report is a bit more ambivalent. There is no areal increase in any of the drought categories but there is no decrease either. Things have not changed at all compared to the previous report. 9.29% of the state is in a moderate drought (level 1 out of 4) and 1.22% is in a severe drought (level 2 out of 4). The drought continues to be focused in northern Illinois entirely.
The report was more of a mixed bag for the Midwest region. While the areas in a severe to extreme drought decreased slightly, the area in a moderate drought increased slightly.
Today will be the 9th straight day without precipitation. Our first chance of rain this week comes tomorrow. The GFS model's total precipitation forecast through Sunday afternoon spits out between a quarter of an inch to nearly a half inch. Most of that will come in the form of rain on late Wednesday into Thursday.
The GFS model's total snowfall forecast through Monday spits out a third of an inch of snow to nearly three quarters of an inch with the heavier end of that range north of Chicago. The first snowflakes of fall could come Friday night into early Saturday. There could be some more light snow or flurries Saturday night and Sunday. Our first snow of the season will be nearly two weeks behind schedule. Typically our first flakes of snow fall around late October.
Focusing on just the GFS model's meteogram for O'Hare highlights late Wednesday into early Thursday for some sprinkles or light rain and then more moderate rain late Thursday into Thursday night. It has light rain on Friday mixing with and changing over to some light snow by Friday night into Saturday morning. It has another round of light rain and snow later Sunday.
The longer range precipitation forecasts keep us relatively dry at first then trend us towards a near normal pattern. The latest 6-10 day forecast has the Chicago area favored for below average precipitation (which can take the form of rain or snow now) from November 13th through November 17th. The longer range 8-14 day forecast also has us outlooked for about average precipitation for the period from November 15th through November 21st.
Here is my 7 day forecast:
Today: Mostly sunny, mild & a bit breezy High: 66
Tuesday: Mostly cloudy, chance of light rain or spotty sprinkles Low: 50 High: 58
Wednesday: Mostly cloudy, chance of light rain late Low: 47 High: 58
Thursday: Mostly cloudy, on & off rain, windy Low: 50 High: 57 (falling temps late)
Friday: Partly to mostly cloudy, windy. rain mainly late Low: 38 High: 47
Saturday: Mostly cloudy, light rain late (light snow possible overnight) Low: 32 High: 41
Sunday: Partly to mostly cloudy, light rain or snow possible late Low: 30 High: 42