Late summer conditions prior to a fall cold front
After a couple of warm and humid days, a cold front is pegged to bring some slightly drier air by the end of the week. A significant cool down is not expected though. Even with a front crossing, rain chances will remain slim. This is opposite what occurred over the summer as rain actually helped to limit excessive heat, read more about that HERE.
Today and Tonight: The afternoon will be partly sunny with a stray shower or thunderstorm possible. Look for high temperatures to near 90 degrees with some humidity. The overnight hours will be quiet and mostly clear with low temperatures in the low 70s.
Up Next: The middle of the week, Wednesday and Thursday, will be mostly sunny and warm with highs in the low 90s. A weak cold front will pass through on Thursday, likely without rain. By this weekend though, we will notice a change. The biggest difference will be a drop in humidity. This drop will allow overnight temperatures to fall into the mid 60s while afternoon temperatures remain in the mid 80s. Outdoor plans for the upcoming weekend, including LSU Homecoming, appear to be in great shape.
The Tropics: Hurricane Maria is positioned 210 miles southeast of Cape Hatteras with a minimum central pressure of 970mb and maximum sustained winds of 75mph moving north at 7mph. Tropical Storm conditions are expected in parts of eastern North Carolina and storm warnings have been posted for the Outer Banks. 2-4 feet of storm surge, 1-2 inches of rain and wind gusts over 40mph will be possible Tuesday and Wednesday. Hurricane Lee is a small but strong storm with 100mpg winds in the central Atlantic. Going nowhere fast, Lee will remain a fish storm, eventually curving out to sea.
A weak upper level trough over the central Gulf Coast will continue to trigger showers and thunderstorms through Tuesday. Rain coverage will not exceed 20 percent across the 13 Parish, 3 County forecast area. The best chances will be south and east of Baton Rouge, closer to the coast. By Wednesday, the trough will be replaced by ridging effectively shutting down convection. A mid-level ridge will dominate through Thursday and associated subsidence will lead to much warmer than average temperatures. Highs will be well into the low 90s both days. On Thursday, a shortwave trough digging through the Eastern U.S. will send a weak cold front toward the Gulf Coast. This front will be moisture starved, but will be followed by some lower dew points. By Friday, humidity will be reduced. The dry air will stay in place with high and low temperatures down about 5 degrees for the upcoming weekend. There is considerable uncertainty as to how the forecast plays out into next week. The GFS model shows an extensive ridge building across the central U.S. and Gulf Coast that would lead to hot and mainly dry conditions. Meanwhile, the ECMWF model is painting a different picture—a shortwave trough moving through which would keep temperatures near average with a better chance of showers and thunderstorms.