Oct 18 | Climate Review and Weather Forecast
This week brought some cooler weather just in time for the harvest moon. Temperature this week ranged from the high 40s in northern Illinois to the high 50s in southern Illinois, right around 1 degree of normal. The lack of humidity allowed nighttime temperatures to regularly dip into the 30s, and get below freezing for many places on a couple of nights. Some of the more impressive nighttime lows this week included 25 degrees in Mount Carroll and 27 in Springfield. Even Carbondale dipped below freezing one night. The first fall freeze came right on time in northern and central Illinois, and 1-2 weeks ahead of average in southern Illinois. Still, October to date has been 1 to 3 degrees warmer than normal so far.
We had another dry week in Illinois, with only the northeast part of the state picking up any rain at all, but still mostly less than a tenth of an inch. The northern half of the state has been 1 to 4 inches drier than normal stretching back to mid-September, and parts of northwest Illinois have had a top 5 driest first half of fall on record. This includes Freeport, which has now been rain free for 23 consecutive days, the 10th longest such streak on record there. The Drought Monitor expanded moderate drought throughout most of the state north of Interstate 74, and introduced severe drought in northwest Illinois in response to the dryness. While the mild temperatures and lack of rain continue to make for good harvest weather, dry soils and even drier grain have really bumped up fire and blowing dust risk, two things that everyone should take note of as they’re working in the fields or simply driving around the state. River levels continued to decline, including on the Mississippi River where, once again, Tower Rock is walkable from the Missouri side.
Looking ahead, our 7-day forecast continues to look completely dry across Illinois. Temperatures will steadily increase this weekend and early next week with highs pushing into the upper 70s. A cool down is likely on its way toward the end of next week, but the week 2 outlooks and the newly released outlook for the month of November still show a propensity for milder temperatures as we move into late fall. That same week two outlook shows the best chances for near normal precipitation, which is quite a change from the dry signal we’ve had since mid-September.