60s By Sunday But Is Snow Possible By The Following Weekend?
Warm Great Lakes Fueling Early Season Snow
It has certainly been cold enough for snow here at times the past few days. O'Hare's low of 29° Wednesday morning was the coldest since early April. Several spots this morning also dipped into the 20s again. So far no snow for northern Illinois. We should normally have about .2" by this point. If you want some snow, head north.
A significant lake-effect snow fell Tuesday into Wednesday this week. The video above is from Gaylord, Michigan which saw record snowfall. Snow piled up to almost a foot deep in parts of the Great Lakes. 17.9% of the northern Great Lakes region now has snow cover with an average depth of a half inch. Nearly twice as much of the region has snow cover compared to this point last year. The average snow depth there now is around a half inch compared to just a tenth of an inch a year ago.
Gaylord, Michigan in the northern part of the lower Peninsula broke a record for snowfall with 11.7" on Tuesday. That is the most they have seen in a single calendar day in November.
It was an ideal set up for lake-effect snow. Unseasonably cold air blew over unseasonably warm water in the Great Lakes. The region saw a warm October and that helped heat up the water several degrees above normal. Most of the Great Lakes are unusually warm for this point of the year. According to NOAA, the average water temperatures of all six Great Lakes has set a daily warm record since September 29th. Some of the lakes have even set record temperatures for this time of the year. The greater the difference in temperature between the cold air blowing over the lakes and the temperature of the relatively warmer water in those lakes, the more snow can be squeezed out during lake-effect snow events. This fall has the potential to see more big lake-effect snowstorms in the Great Lakes.
Could the Chicago area be in line for some heavy lake-effect snow? The potential is certainly there. What we need now is a cold wind off the lake to blow into the city. No signs of that in the immediate future but looking ahead to a week from Saturday offers a glimmer of hope for snow fans. More on some snow potential below in this post.
Thawing Out By The Weekend
Today will be the 5th straight day with temperatures below average. November is now running about 8° below average.
Average highs for today's date are around 54°. The GFS Model has our highs today failing to get out of the 40s for the 4th straight day. Highs this afternoon should top out in the lower to middle 40s. More cloud cover today will keep us chilly with highs around 10° below average.
Friday's highs should hit at least 50°. The GFS Model has our highs tomorrow topping out in the lower 50s with the help of more sunshine and a southerly breeze.
I am expecting at least middle 50s for Saturday and then soaring past 60° on Sunday. The GFS Model has our highs Sunday into the lower to middle 60s. That would be 10° or more above average. 60° or warmer highs could stick around then through at least Tuesday.
The GFS temperature anomaly forecast for Monday afternoon keeps this unseasonably warm pattern coming into early next week. It has most of the middle part of the country between 10° to 20° above average.
So we'll bounce back from 40s for highs today into the 50s for Friday. Keep in mind the combination of temperatures and wind will make it feel like the 30s most of today with wind chills dipping into the 20s overnight.
Gusty southerly winds will combine with sunshine to bring about the warm up that starts tomorrow and continues into the weekend.
Only a slight chance for some spotty sprinkles early today but basically a dry forecast through Monday.
Warm Up Peaks Early Next Week
The National Blend Of Models has our highs warming into the 60s Sunday and staying at 60° or more through Tuesday. The warmest day would come on Monday with a high of 64°. Temperatures drop fairly dramatically by the end of next week. Some models are even hinting at some snow by next weekend.
The longer range temperature outlooks also suggest a trend towards a relatively cooler pattern by the end of next week. The 6-10 day outlook has us favored for above average temperatures overall from November 9th through November 13th. The longer range 8-14 day forecast favors us for cooling to near normal temperatures overall from November 11th through November 17th. Average highs for this period are in the upper 40s to lower 50s.
The even longer term 35 day temperature anomaly forecast once again has northern (and central) Illinois staying near normal overall all the way through the first week of December. Downstate Illinois is still outlooked to be between 1° to 3° below average. This forecast covers the period from November 2nd through December 7th. 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.
Dry Pattern For Now
Today should be the 5th dry day in a row and that streak into early next week. The next decent chance of rain isn't until Tuesday.
The most recent US Drought Monitor analysis was released last Thursday. It was the third report in a row to bring good news for Illinois. It did not include our rainfall this past Thursday and Friday. Here is a recap from that report:
The area considered in either a moderate or severe drought diminished at least slightly. Unlike the previous analysis, this most recent one shows even the area considered "abnormally dry" dropped in coverage.
The news for the Midwest region was good almost across the board. The area in either a moderate or severe drought decreased slightly. The 1.20% of the area in an extreme drought did not change from the last report.
October certainly helped put a dent in our drought. The 30-day precipitation departure from average map shows just how much rain we've seen since early October. Most of the Chicago area has received between 150% to 300% of average rainfall since early last month.
The GFS model's total precipitation forecast through next Monday keeps us dry.
I ran the precipitation forecast out through next Wednesday afternoon. It spits out some light rainfall for late Tuesday into early Wednesday morning. Most areas are forecast to see bit over a tenth of an inch of rain in total during the period.
For fun, I also ran out the total snowfall forecast for the next ten days. It hints at some light snowfall possibly coming a week from Saturday. There is a range of snowfall between about a third of an inch to nearly an inch and a half. This would be the result of some potential lake-effect snow. Stay tuned.
The GFS model's meteogram for O'Hare keeps us dry through Monday and then brings in the next chance of rain later Tuesday into early Wednesday. More rain is forecast for a week from this Thursday and then some light snow and rain for a week from this Saturday.
The longer term precipitation outlooks still favor us for above average precipitation starting early next week and lasting through the middle of the month. The latest 6-10 day forecast has the Chicago area favored for above average precipitation (which can take the form of rain or snow now) from November 9th through November 13th. The longer range 8-14 day forecast also has us outlooked for above normal precipitation for the period from November 11th through November 17th although the probabilities drop a bit.
Here is my 7 day forecast:
Today: Partly to mostly cloudy High: 46
Friday: Sunny & not as cold Low: 34 High: 52
Saturday: Mostly sunny & milder Low: 39 High: 58
Sunday: Mostly sunny Low: 44 High: 63
Monday: Partly to mostly sunny Low: 49 High: 65
Tuesday: Partly to mostly cloudy, chance of rain late Low: 49 High: 60
Wednesday: Mostly sunny Low: 30 High: 49