Area Forecast Discussion (AFD)
Issued by Huntsville, AL (HUN)
305 FXUS64 KHUN 221130 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 530 AM CST Wed Nov 22 2017 .UPDATE... For 12Z TAFS. && .NEAR TERM...(Today) Issued at 315 AM CST Wed Nov 22 2017 Surface analysis from this morning shows that the dry cold front has shifted through the S. Middle TN/N. AL region. Northerly winds are steadily increasing to to the 5-8kt range at the surface. Model soundings and KHTX VWP are showing deep northerly flow through ~10Kft behind the front, with winds 25-35 kt off the surface. Its safe to saw the cold air advection is underway. For the rest of the day, expect temps to only rebound into the upper 40s/low 50s across the region which would be around a 10 degree difference from yesterday. With strong ridging re-establishing along with a strong low to mid level subsidence inversion over the area, rain chances will be at 0 percent. .SHORT TERM...(Tonight through Friday) Issued at 315 AM CST Wed Nov 22 2017 Little change to the overall pattern expected through Friday. Surface ridging will become elongated over much of the SE US by Thanksgiving with the ridge axis north of the area. The low-mid level subsidence will remain in place through tomorrow night but gradually weaken as the ridge shifts east through Friday. With plenty of dry air and subsidence lingering over the region, do not expect any chance of precip. For temperatures, expect widespread freezing conditions Thanksgiving morning thanks to the on going cold air advection, light winds, and clear skies. Temps will start to moderate by Thanksgiving afternoon as the cold air advection begins to wane. A few locations mainly west of I-65 will deep below freezing Friday morning, but temps will be quick to rebound into the upper 50s/low 60s across the area. .LONG TERM...(Friday night through Tuesday) Issued at 315 AM CST Wed Nov 22 2017 Yet another reinforcing cold front will be on the doorstep of the cntrl TN Valley at the start of Fri night. The front will get its surge sewd from another strong dome of high pressure building swd across the Plains states. Prior to the onset of the frontal passage later in the day on Sat, near seasonal temps look to be in place across much of the region, with lows Fri night mainly in the lower 40s followed by highs climbing into the lower 60s Sat. Other than a slight increase in cloud cover out of the WNW, little fanfare is xpcted with the passage of the cold front Sat. The sfc high will begin to build ewd into the TN/OH Valley regions for the second half of the weekend period, with slightly cooler air streaming into the area from the N. Lows Sat night look to fall predom into the mid/upper 30s while highs on Sun trend fairly mild, with afternoon temps mainly in the mid 50s. After a chilly morning on Mon, with lows falling into the lower 30s for most locations, high pressure will then gradually move ewd, or more into the mid Atlantic Basin, heading into the first half of the new work week. This should allow for a gradual warming trend, as highs trend closer to 60F Mon afternoon while lows that night climb back to near 40F. This trend continues into Tue, with highs climbing more into the mid 60s, while lows Tue night remain predom in the mid 40s. A deep upper trough pattern carving thru the Plains states will help push another cold front close to the TN Valley area around the middle of next week. This frontal boundary may bring with it our next chc of rain/showers as well, with moisture return increasing out of the S/SW along/ahead of this oncoming cold front. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 530 AM CST Wed Nov 22 2017 VFR conditions will prevail through the 12z TAF period. Expect gusts to increase to around 20 kt beginning around 15z and persisting through 20z. North winds will subside before sunrise and drop to 5 kt or less by nightfall. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && $$ NEAR TERM...Barron SHORT TERM...Barron LONG TERM...09 AVIATION...Barron For more information please visit our website at weather.gov/huntsville.