Area Forecast Discussion (AFD)
Issued by Huntsville, AL (HUN)
000 FXUS64 KHUN 131149 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 649 AM CDT Sat Oct 13 2018 .UPDATE... For 12Z TAFS. && .NEAR TERM...(Today) Issued at 357 AM CDT Sat Oct 13 2018 Temperatures across the area this morning currently range from the mid/upper 50s to around 60 degrees, which is about 5-10 degrees warmer than this time yesterday. This is thanks to the cloud cover in place across the region, associated with a cold front (draped SW to NE) meandering S/SEwrd through the CWFA. Regional METARs show this feature's passage, with N/NWrly winds picking up in its wake. High pressure at the sfc is building into the area from the NW, with weak CAA ongoing as well. Time sections show these low clouds hanging around through most of the day today, and therefore high temps this afternoon will be a couple of degrees cooler than yesterday. Values should top out in the middle to upper 60s (with a few lower 60s possible in the higher terrain locations of Southern Middle TN). A dry day is expected, though clouds/moisture will increase through the column overnight with a disturbance approaching the area in SW flow aloft (and the sfc ridge departing to the E helping to turn the winds more SErly). .SHORT TERM...(Tonight through Monday) Issued at 357 AM CDT Sat Oct 13 2018 Much of the rainfall/lift with this approaching disturbance will remain just N of the CWFA, though due to model guidance differences/uncertainty in exact coverage, have opted to retain PoPs beginning at 00Z tonight. PoPs increase through the night, but again, they will be tapered higher N/lower S. The disturbance moving through will stall a cold front just NW of the area, with higher PoPs again N of the TN River and lessening as you move S across the CWFA. By this time as well, the subtropical ridge strengthens over S FL, which places our area on the Nrn periphery of the ridge. This pattern generally is a wetter one for our area locally, with disturbances passing in SW flow aloft. The atmosphere will recharge in-between disturbances, and bringing showers to the area through much of the week ahead. Daytime temps will fall through the day Monday with the cold front stalled across the region, with morning lows Tuesday falling into the 50s. .LONG TERM...(Monday night through Friday) Issued at 357 AM CDT Sat Oct 13 2018 Much of the extended is a rinse-and-repeat forecast from what occurred Monday. Disturbances in SW flow aloft will affect the area on the Nrn periphery of the upper ridge to the SE. As such, rain is in the forecast for Tuesday and Tuesday night, with a dry stretch for Wednesday and Thursday in the wake of another cold front. High pressure builds into the area from the NW during this time and quickly shifts to the E. This will help return flow to the SE, increasing moisture ahead of our next weathermaker slated to arrive late in the extended. Model runs continue to indicate heavy rainfall may affect the area during late Friday night through the wee hours next Sunday. An upper trof will swing across the Nrn CONUS, but runs into a strengthening H5 ridge parked over S FL. With stout SW flow aloft and a disturbance crossing the region, PWats are near/above the daily record max values for this time frame (per the SPC PWat Climo page). I'm not sounding the flooding alarms just yet, but this will be something to watch unfold as the week progresses. Stay tuned! Temps during the extended will be seasonable, and even a few degrees below normal during this time. Considering normal highs this time of year are in the mid/upper 70s, highs in the upper 60s to around 70 are a much-welcomed change from less than week ago when we were in the 90s! && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) Issued at 640 AM CDT Sat Oct 13 2018 Low clouds arnd 3-4kft will linger for much of the first half of the TAF period, with showers in the vicinity of the terminals possible by sunset this evening. Spotty -RA will overspread the region after midnight, lingering thru the end of the TAF period. Conds aren't expected to drop below MVFR during this time, as rain will generally be light over both KMSL/KHSV. Heavier rain should remain N of both sites thru 14/12Z, but will increase in intensity after this time. Winds will slowly shift around to the SE, remaining AOB 10kts. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && $$ NEAR TERM...12 SHORT TERM...12 LONG TERM...12 AVIATION...12 For more information please visit our website at weather.gov/huntsville.