After a rather chilly beginning to the week, we should expect some showers and thunderstorms to move into the area overnight Thursday and into Friday.Tuesday was a relatively cool day across the mid-south. The high temperature here in Bowling Green only reached 62 degrees at the Ag farm (Source: Kentucky Mesonet). To give you some perspective for how cool this really is for late-September in south central Kentucky, the average high temperature on Tuesday was 77 (Source: NWS). Furthermore, Bowling Green saw a high temperature of 86 on September 29, 2008 and 83 on September 29, 2007. You have to go back to 2001 to find a cooler high temperature (61) for Bowling Green on any day in the month of September (Source: MRCC).
But we can expect to see a slight warm-up today and tomorrow as we receive continued sunshine and winds shifting from the north today to the south by tomorrow evening. The high temperature this afternoon will threaten to reach 70 with an overnight low in the mid-40s. The central U.S. will warm-up quite a bit more than us today as a trough makes its way toward the Rockies. This will pull warm air from Texas and Mexico into the Plains region and even as far north as central Canada. In fact, the Dakotas are likely to receive temperatures in the 70s this afternoon. Assuming that the cap is broken with the surge in daytime heating, this set-up has led the SPC to place a bulls-eye over Nebraska this afternoon and evening for severe hail and wind with the potential for tornadoes.
This system will advance east overnight tonight and should cause some problems for folks from ArkLaTex north to Missouri on Thursday. As the surface low pressure center enters Iowa, warm and moist air from the Gulf will move into eastern Texas and the lower Mississippi valley. It wouldn’t be out of the question to see some 80s creep into extreme southern Illinois and southwestern Kentucky tomorrow afternoon. The Bowling Green area, however, should expect to see a high temperature in the low- to mid-70s. The main threats again appear to be hail and damaging winds for the lower Mississippi valley.
For us, it appears that the system will pass overnight on Thursday and into the early morning hours of Friday. Beginning around midnight tomorrow night, the low level jet at 850 mb will quickly amplify to about 40 knots out of the south/southwest. Normally this would be a good-looking set-up for severe weather in south central Kentucky, but the front will almost certainly lose some of its punch overnight with the lack of daytime heating. This is especially true given that the low temperature tomorrow night will be somewhere in the mid-50s with a dew point of 50 at best. So Bowling Green won’t receive very much in the way of severe weather. Beginning around 3-5 in the morning, south central Kentucky will get some consistent rainfall that will be heavy at times along with a rumble or two of thunder and some gusty winds at times. By the time the front moves out of the area by noon on Friday, the SPC indicates that about 0.5 inch of rain will have fallen across the area.
Check back in on Friday for a quick look at the weekend and just how much this passing cold front will cool us down.