8:25 p.m. Update: Thunderstorms have made it into the northern suburbs, mainly north of the Beltway, with areas of heavy rain, gusty winds and possibly small hail. They should move out of the area or dissipate over the next couple hours.
From 4 p.m.: Today’s temperatures in the mid-80s to near 90 are about to be a thing of the past as the first in a series of cold fronts pushes through late tonight. A second front, arriving at some point tomorrow, brings even cooler air into the region, giving us our first real taste of fall weather around here. But first, we may have to dodge an isolated to widely scattered shower or storm into the night and more rain threats tomorrow.
Through Tonight: There could be a few showers or a storm around this evening and during the early night. Right now, coverage appears to be rather low and maybe focused on the western half of the area. However, any storm could become severe with wind damage the primary threat. Temperatures should not fall too far though as the first front won’t get entirely through ‘til near sunrise. Look for lows in the low-to-mid 60s in the suburbs to the upper 60s downtown.
Tomorrow (Thursday): We should see a fair amount of clouds during the day, also mixed with some sun here and there as well. During the midday or afternoon, as a second cold front nears, showers and a rumble of thunder may break out again. Odds are decent for some rain, about a 40-50% chance. A sometimes quite gusty (sustained near 20 mph with gusts past 30 mph) north and northwest wind may make it feel somewhat blustery. Daytime temperatures probably don’t get much higher than the low-to-mid 70s or so.
Desert rains: The sunny deserts of Southern California have dealt with some flooding rain from thunderstorms over recent days. Yesterday was particularly intense in many areas, including spots around Palm Springs where record rainfall led to highway closures thanks to flash flooding. Numerous small fires were also started because of lightning from the storms, and several fire fighters were injured by one lightning strike. In addition, parts of Joshua Tree National Park sustained significant damage from flooding .
Minnesota fires: Several fires are burning across Minnesota currently. The largest is the Pagami Creek fire near the border of Canada, and it is now at over 100,000 acres of charred remote forest land. The Pagami fire, started by lightning, is the largest in Minnesota since 1918. Check out some neat imagery of the fire, and smoke which has poured all the way into the Chicago area.
Pollen update from Walter Reed: Tree pollen is MODERATE, grasses are also MODERATE, while weeds are running HIGH.