352 FXUS64 KHUN 281819 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 119 PM CDT Mon Sep 28 2020 .UPDATE... For 18Z TAFS. && .NEAR TERM...(Rest of Today) Issued at 1002 AM CDT Mon Sep 28 2020 The well-advertised cold front is approaching the doorstep of NW Alabama this morning, with a broken line of showers and thunderstorms ahead of the front. This activity will traverse the region through the day today, with a few stronger storms possible this afternoon. The main threat will be for borderline-severe wind gusts, though this should be very isolated, at best. A vast majority of the incoming precipitation is showery in nature, though a line of storms is trying to hold together just west the KGWX radar. Right now, this is the part of the line to watch, but it is well below severe limits at this time. Later in the day, shear values creep upward as you head east of the Interstate-65 corridor, so this will be something to keep an eye on on the happen chance the storms are able to utilize those values and try to rotate. Otherwise, a relatively benign fropa is expected with showers and a few storms here or there (some of which may become strong to borderline-severe). The main change with the update this morning was to update the PoPs for today to make them more in line with radar trends/expectations thru this evening. Storms will end from west to east by/after 00Z tonight, with some light rain maybe wrapping around overnight. Lows Tuesday morning will fall into the lower 50s. .SHORT TERM...(Tonight through Wednesday) Issued at 405 AM CDT Mon Sep 28 2020 The front in most guidance slows its eastward movement tonight. This is mainly due to a very amplified ridge off the eastern seaboard. This will likely keep scattered to likely rain chances in the forecast, primarily east of the I-65 corridor. Further west rain will be much more spotty. The parent low (associated with the front) over the eastern Great Lakes region moves more to the north on Tuesday. As it does so, a closed low forms along the trough axis of the front and moves quickly southeastward. Very strong forcing is associated with this feature and as it moves into northern Alabama during the afternoon hours, and models show some elevated and surface instability associated with it. The atmosphere will be fairly moisture starved by that time. However, given the strong forcing and with some lingering moisture east of the I-65 corridor included scattered showers and isolated thunderstorms in forecast on Tuesday. It should be a bit chilly compared to what we have been used to with stronger cold air advection continuing behind the front. Cloudy conditions and highs only in the lower to mid 60s are expected. Tuesday night the upper low pushes well east of the area into the Carolinas. This should put an end to any lingering precipitation. Even drier air will push into the area with lows dropping into the mid to upper 40s. Despite the return of sunshine, highs will struggle to climb to around 70 degrees in most locations on Wednesday. .LONG TERM...(Wednesday night through Sunday) Issued at 405 AM CDT Mon Sep 28 2020 The extended part of the forecast will be characterized by fair weather and a bout of below normal temperatures as we head into early October. In wake of a strong cold front earlier in the week, a cool, dry air mass will filter into the area. This will result in temperatures running as much as 10-20 degrees lower than normal for this time period (especially by the weekend). Thursday may well be the warmest day as plenty of sunshine will allow temperatures to at least warm into the low to perhaps mid 70s in the somewhat modified air mass. On Friday, a stronger push of cold air will arrive as a secondary lobe of energy will rotate around a parent upper low over the Great Lakes into this Ohio valley. This will sent a dry cold front into the region, bringing in some Canadian air into the area. This stronger push of cold air will serve to magnify this cool, dry air mass and result in some of the coolest temperatures we have seen since early last Spring. Highs will struggle to climb above the lower to mid 60s on Friday and Saturday, with some areas on the Cumberland Plateau only reaching the upper 50s. Crisp and cool weather is expected overnight thanks to the clear conditions and dry air mass, with lows in the lower 40s being common. As the center of the surface high shifts slightly to the east on Sunday, we may get a little air mass modification as winds briefly veer to the SW, allowing highs to return to around 70 degrees. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) Issued at 100 PM CDT Mon Sep 28 2020 MVFR conds will prevail at both KMSL/KHSV thru the afternoon as showers and a few storms ahead of a cold front push across the region. Winds will gust up to 20kts at times ahead of the front, with winds becoming northwesterly in the wake of the front. Wind gusts up to 15kts will be possible through the evening hours, with winds subsiding after midnight to arnd the 5kt range. Low clouds will push off to the E this evening, giving way to OVC clouds arnd 8-10kft between 29/08-12Z. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && $$ NEAR TERM...12 SHORT TERM...KTW LONG TERM...AMP.24 AVIATION...12 For more information please visit our website at weather.gov/huntsville.