10 In A Row & Counting
Above Average Streak Stretches On
Yesterday was the 10th day in a row with above average temperatures. The high was 67° or just 1° above average. The low was 65° or 16° above average. Since the average temperature for a day is the high and low divided by 2, the average temperature on Wednesday was 66° or 8° above average. October so far is running nearly 12° above average.
Our current streak of days with above average temperatures that started in late September could stretch to at least 21 days. We even have the possibility of an 80° high both Saturday and Sunday.
The GFS Model has our highs hitting 70° or warmer for most of us today. The average high for today's date is 67°.
This weekend will be the two warmest back to back days through most likely the rest of this month. The GFS Model temperature anomaly forecast for Saturday afternoon has our temperatures between 15° to 20° above average. That would mean a high near 80° or warmer on Saturday. Temperatures on Saturday will be highly dependent on just how much cloud cover we end up getting.
I'm still checking on the forecast for the start time of the Chicago marathon on Sunday. The race begins at 7:30 AM. It looks like it will be a rather mild morning. Temperatures at 7 AM are forecast to be around 70°. Normal lows for Sunday morning are in the middle to upper 40s.
Sunday should round out a warm weekend. Highs could reach to 80° or even a few degrees warmer.
A bit breezy again today with winds out of the northeast. Winds will shift to the southeast on Thursday. More mild October temperatures with highs near 70° today and into the lower 70s tomorrow. Maybe a few peeks of sunshine today by generally cloudy today and tomorrow.
The threat of rain ramps up this evening and stays fairly high tonight, through Thursday and into Friday morning. Scattered showers look likely and even a few isolated thunderstorms are possible.
"Real" Fall Still On Hold
For those who like cool, crisp fall weather it looks like you will have to keep waiting for its arrival. The National Blend Of Models has our highs above average for the next eleven days in a row. The weekend will see the warmest temperatures during this streak with highs possibly hitting 80° or more both days.
The blue blob is growing out west on the long range temperature outlooks but we are still firmly in the red. The 6-10 day outlook has us favored for above average temperatures overall from October 11th through October 15th. We are in the 70% to 80% probability contour, the highest for this outlook. The longer range 8-14 day forecast also favors us for above average temperatures overall. It covers the period from October 13th through October 19th. We are in the 60% to 70% probability contour, the second highest for this outlook. Average highs for this period are in the middle 60s.
The even longer range temperature anomaly forecast keeps the overall mild pattern going into next month. The longer term 35 day temperature anomaly forecast still has all of the Midwest and most of the country outlooked for above average temperatures overall all the way through nearly the first week of November. We are outlooked to be between 5° to 7° above average overall for the period from October 3rd through November 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.
More Active Pattern For A Change
Models are suggesting a more active pattern for rainfall starting late today. So far October is running .40 of rain below average and O'Hare is down 2.36" below average since the start of September. The rainfall that is predicted will be especially welcome for Lake and McHenry counties which are still mired in a serious drought.
Here is a recap from Friday's post:
The areas in a severe drought (level 2 out of 4) and extreme drought (level 3 out of 4) areas have more than doubled compared to last week. The area in a moderate drought increased slightly. Northern Illinois is being hit the hardest by the drought.
A side-by-side comparison shows the change between September 28's drought conditions and the prior analysis back on September 21st.
Here is a summary of the impacts the ongoing drought is having on northern Illinois from the National Weather Service:
Volunteer observers across far northern Illinois indicate much lower then typical stream flows on area creeks and rivers, particularly along Beaver Creek and the Kishwaukee River.
Reports also indicate that lawns have gone dormant and there has been some stress to the trees. Few impacts to agriculture have been received recently, though the dry conditions and stressed crops have resulted in an early start to the harvest season across northern Illinois. Data available from the Illinois State Water Survey, USGS, and NCEP indicate that soil moisture, groundwater, and surface water levels remain below normal.
The drought news was also discouraging for the Midwest as a region. The areas in a moderate, severe and extreme drought all expanded.
An analysis of the past 30 days of rainfall that includes are weekend rain shows just only slight improvements for portions of the area. North of the city in eastern Lake County and south of the city for southern Will County and most of Kankakee County benefitted from rainfall over the weekend. Most of our northern Illinois is still rather parched for the period, only receiving about 25% to 75% of average rainfall over the past four weeks.
The GFS model's meteogram for O'Hare has several periods of potential rainfall. The greatest chance is tonight, through Thursday and into Friday morning. More spotty showers possible over the weekend but there should be many more dry hours than wet ones. Another shot of unsettled weather arrives late Monday and continues through Tuesday.
The GFS model's total precipitation forecast through Monday morning suggests most areas would pick up around a half inch of rain. Parts of northern Indiana could see nearly an inch of rain.
Both of the longer range rainfall outlooks have us outlooked for above average precipitation during the middle of this month. The latest 6-10 day forecast has the Chicago area favored for above normal rainfall from September October 11th through October 15th. The longer range 8-14 day forecast has us outlooked for above average precipitation from October 13th through October 19th. A positive sign for the parched portions of northern Illinois.
Here is my 7 day forecast:
Today: Mostly cloudy, scattered showers possible late High: 71
Thursday: Cloudy, occasional showers, isolated thunderstorms possible Low: 63 High: 72
Friday: Partly to mostly cloudy, sct. showers possible Low: 63 High: 76
Saturday: Partly to mostly sunny Low: 63 High: 80
Sunday: Partly to mostly sunny, pm sct. showers possible Low: 66 High: 81
Monday: Partly to mostly sunny, sct. showers possible Low: 64 High: 77
Tuesday: Partly to mostly sunny, sct. showers possible Low: 59 High: 73