Area Forecast Discussion
Issued by NWS Huntsville, AL
Issued by NWS Huntsville, AL
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210 FXUS64 KHUN 241301 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 801 AM CDT Tue Sep 24 2024 ...New NEAR TERM... .NEAR TERM... (Rest of Today) Issued at 802 AM CDT Tue Sep 24 2024 Todays focus will be on a mid level trough and associated cold front slowly making its way east across the area. Current observations indicate the front is still well to our west over Missouri and Arkansas. Despite this, a band of prefrontal clouds and showers is moving through NW AL and TN. Given that this activity is far removed from the front, it is expected to wane as it continues to push east through the morning. Better forcing will be present this afternoon as the front draws closer to support scattered shower and thunderstorm development across the area. HREF models continue to support 1000-2000 J/KG of CAPE along with 40-45 KTS of Bulk shear. This will be sufficient for strong to severe storm potential this afternoon with the main threats being damaging winds and frequent lightning. The highest CAPE and SHEAR values are forecast for NW AL, giving us greater confidence in the low severe threat materializing there. We will have to keep an eye on ongoing showers and overcast conditions to see if that inhibits fuel for afternoon storms. While storms will decrease with the loss of diurnal heating, rain is expected to continue along the front through the night, please see the short term forecast for additional rainfall details. && .SHORT TERM... (Tonight through Thursday night) Issued at 233 AM CDT Tue Sep 24 2024 The front will drift into NW AL this evening and lightly stall, with lingering showers/tstms continuing along/ahead of the weak sfc boundary, although the loss of buoyant energy will likely offset the prob for any additional stronger storms. The influx of slightly cooler air may at least allow for lows early Wed more in the mid/upper 60s. The unsettled/wet pattern will then continue into the middle of the week, as the upper trough pattern evolves into a closed low over the Midwest/Mid South areas. Additional periods of showers/tstms along/ahead of the stalled front are expected into Wed night, although considerable cloudiness/rainfall may limit much in the way of airmass destabilization. Rainfall amounts Tue/Wed predom look to be around 1-3 inches. Given these conditions, highs on Wed may struggle to surpass the upper 70s, with lows Wed night falling into the lower/mid 60s. The pattern will then shift to Potential Tropical Cyclone Nine out of the western Caribbean lifting north and strengthening into a hurricane prior to landfall along the eastern Gulf Coast/Big Bend area of FL Thu night. Outer bands of showers/tstms associated with the oncoming tropical system will spread northward into the region during the day Thu, especially east of I-65. The eventual track of this system remains uncertain, although its likely to pass east of the area into GA and the Carolinas. Nevertheless, additional rain totals Thu/Thu night could range from 2-4 inches, especially east of I-65. Rainfall within these tropical bands may certainly be heavy at times and a Flood Watch may be needed starting Thu if not earlier. Gusty winds are also possible across NE AL Thu/Thu night, although this threat may be limited with a more eastward track. With abundant cloud cover/rainfall, highs on Thu may trend more in the mid 70s, with lows that night again falling into the lower/mid 60s for most spots. && .LONG TERM... (Friday through Monday) Issued at 233 AM CDT Tue Sep 24 2024 The forecast going into the Long Term portion will of course be dependent on the eventual track of the tropical system, but the rainfall impacts to the area may transition more to the upper low over the Mid South/lower MS Valley regions as opposed to the remnant tropical system exiting to the ENE. Medium chances for showers/tstms (30-50%) are expected on Fri, as the upper low begins to drift eastward. However, given the slower movement of this feature, rain chances look to taper off this weekend to around 20-30%. In fact, any additional rainfall looks to remain as showers, although an isolated storm cannot be ruled out Sun afternoon. With less cloud cover/rainfall, highs this weekend look to climb back into the lower 80s/near 80F. Those rain chances increase slightly on Mon, as the upper low begins to lift into the OH Valley area. Highs on Mon also look to trend more in the upper 70s/near 80F. Lows this weekend and into next week look to remain in the lower/mid 60s. && .AVIATION... (12Z TAFS) Issued at 639 AM CDT Tue Sep 24 2024 Mid/high clouds continue to spread into the area from the west heading into the morning hrs this Tue, as a weak cold front approaches the MS River. As the front moves eastward closer to NW AL, sct/perhaps num shra/tsra are expected to develop along/well ahead of the front as this activity crosses into NW AL going more into the afternoon period. A TEMPO group has been added mainly in the 20-24Z time frame to account for reduced cig/vis due to any shra/tsra closer to the airfields. A PROB30 group was then added this evening for lingering shra as the front crosses into NW AL and stalls. Lower cigs are possible late tonight although the prob is not very high attm. Light/var winds will also become SW around 8-9kt with higher gusts late this morning. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...None. TN...None. && $$ NEAR TERM...RAD SHORT TERM....09 LONG TERM....09 AVIATION...09