082 FXUS64 KHUN 161422 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 922 AM CDT Fri Aug 16 2019 .NEAR TERM...(Rest of Today) Issued at 922 AM CDT Fri Aug 16 2019 High pressure will settle into the region today, with mostly clear skies persisting across the TN Valley. The upper flow pattern will remain fairly zonal, though heights will be slightly higher than yesterday. Given higher heights, clear skies and lighter winds, temps are expected to rise a degree or two higher day, with with highs expected in the lower to mid 90s. The previous forecast remains on track, so no major changes were necessary. .SHORT TERM...(Tonight through Sunday) Issued at 256 AM CDT Fri Aug 16 2019 After another clear and calm night, an even warmer day is possible on Saturday as the upper ridge continues to build northeast into the Mid-South and Tennessee Valley region this weekend. Latest guidance indicates slightly higher thickness values and temperatures, with mid 90s highs more common -- and potentially a couple sites peaking in the upper 90s. Expect another dry day, thanks to strong subsidence from the ridge and the lack of any lifting mechanism. A weak front across South Central Alabama may move slightly to the north (closer to the I-20 corridor) on Sunday, and serve as a focus for isolated to widely scattered convection. As a result, we could see an uptick in cloud cover and possibly a few showers and storms in the afternoon. However, most locations will remain dry given the sparse coverage of this activity. .LONG TERM...(Sunday night through Thursday) Issued at 256 AM CDT Fri Aug 16 2019 At the start of the extended period, blocking was evident near the International Date Line north of 40N to eastern Russia. The block's further westward shift from its current position south of the eastern Aleutians should result in a relaxation of troughing that was in place over the lower-48, and return of upper ridging over the Desert SW. At the surface, high pressure situated off of the east coast will continue to bring a southerly flow from a very warm Gulf (sea surface temperatures in the mid 80s to around 90 degrees). Daily high temperatures will remain at summer time levels, into the low/mid 90s. Dewpoints in the low/mid 70s will yield daily heat index values from the mid 90s to around 107 degrees in a few spots. Areal coverage of heat index values above 105 looks greatest on Monday, with coverage slowly falling from Tuesday onward. That said, it still will be very warm to hot temperatures and heat index wise, with values to 105 into the middle of next week. Heat Advisories may be needed for the start of next week if these trends continue. Moisture within the southerly flow along with daytime heating will bring mainly afternoon and early evening showers and thunderstorms for much of the new work week. Model output was not in good agreement regarding placement of showers, so stayed in the 20-30 percent range through the mid week. An eastward moving trough in the westerlies over southern Canada could bring a cold front towards the forecast area late next week. The approach of this boundary will bring somewhat better shower/thunderstorm chances on Thursday. && .AVIATION...(For the 12Z TAFS through 12Z Saturday morning) Issued at 618 AM CDT Fri Aug 16 2019 VFR conditions will prevail at the KMSL and KHSV terminals through the period. Light northerly winds will generally remain below 7 kts and skies will remain mostly clear. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && $$ NEAR TERM...73 SHORT TERM...AMP.24 LONG TERM...RSB AVIATION...73 For more information please visit our website at weather.gov/huntsville.