979 FXUS64 KHUN 282246 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 546 PM CDT Sun Jun 28 2026 ...New AVIATION... .KEY MESSAGES... Updated at 135 PM CDT Sun Jun 28 2026 - A heat wave will occur this week with a Heat Risk value of 3 out of 4 (Major category) to 4 out of 4 (Extreme category). - A Heat Advisory is in effect through 7 PM Tuesday. && .NEAR TERM... (Tonight) Issued at 135 PM CDT Sun Jun 28 2026 Diurnal cumulus should dissipate by around sunset leaving a clear sky overnight. Muggy conditions are expected, but at this point any fog development would be very patchy in nature. Dew points in the lower 70s will keep low temperatures in that ballpark for overnight lows. The Heat Advisory remains in effect overnight due to the warm overnight low temperatures. && .SHORT TERM... (Monday through Tuesday) Issued at 903 AM CDT Sun Jun 28 2026 The 596 dkm 5h anticyclone will shift northeast from northern MS Monday morning to the KY/TN state line on Tuesday. This will enable easterly flow to begin by Tuesday in lower to mid levels, and thus will have to monitor moisture backdooring our area from the east. For now, PoPs of 20% or less will occur during the afternoon hours Tuesday generally east of I-65. High temperatures will reach the 93-97 range in valleys on Monday, and 94-98 on Tuesday (upper 80s to lower 90s atop the Cumberland Plateau). .LONG TERM... (Wednesday through Saturday) Issued at 1056 PM CDT Sat Jun 27 2026 By midweek, the upper ridge will shift from being centered over the Tennessee Valley to the Appalachians. Even so, this feature will largely maintain its hold over the Southeast through the work week. Global models then show it shifting eastward and flattening a bit by the weekend as a series of shortwaves ripple over the Great Lakes region. At the surface, high pressure persists over the Appalachians and Southeastern states through the early part of next weekend. While a very low chance of a few showers/storms is suggested by the NBM for Wednesday and Thursday, the aforementioned pattern indicates that most areas are more likely to remain dry. Although, by late in the week, as the upper ridge shifts a bit more east and flattens, perhaps the return flow would be enough to increase shower and storm chances (20-30%) and bring a more summertime, diurnal pattern to the region. Overall, the main concern will be the continued dangerous heat. Highs are forecast to remain steady in the mid 90s, with some spots potentially reaching the upper 90s (especially over NW AL) each day. Heat indices generally range between 102-110 degrees during this time as well. In addition, NWS HeatRisk is slated to be Major to Extreme (Levels 3 and 4 out of 4) Wednesday through Saturday. This is likely due in part to low temperatures not cooling off much at night, with values forecast to merely drop into the mid to upper 70s each night. WBGTs are also in the upper 80s to around 90 degrees. Therefore, not much relief is in sight, at least through next Saturday. Heat Advisories will likely be issued to account for this heat wave. Make sure to take precautions for the dangerous heat! Wear light- colored loose-fitting clothing, stay hydrated, and take frequent breaks in the shade if you work outside or have outdoor activities! Look before you lock - never leave people or pets in vehicles! && .LONG TERM... (Wednesday through Saturday) Issued at 1056 PM CDT Sat Jun 27 2026 By midweek, the upper ridge will shift from being centered over the Tennessee Valley to the Appalachians. Even so, this feature will largely maintain its hold over the Southeast through the work week. Global models then show it shifting eastward and flattening a bit by the weekend as a series of shortwaves ripple over the Great Lakes region. At the surface, high pressure persists over the Appalachians and Southeastern states through the early part of next weekend. While a very low chance of a few showers/storms is suggested by the NBM for Wednesday and Thursday, the aforementioned pattern indicates that most areas are more likely to remain dry. Although, by late in the week, as the upper ridge shifts a bit more east and flattens, perhaps the return flow would be enough to increase shower and storm chances (20-30%) and bring a more summertime, diurnal pattern to the region. Overall, the main concern will be the continued dangerous heat. Highs are forecast to remain steady in the mid 90s, with some spots potentially reaching the upper 90s (especially over NW AL) each day. Heat indices generally range between 102-110 degrees during this time as well. In addition, NWS HeatRisk is slated to be Major to Extreme (Levels 3 and 4 out of 4) Wednesday through Saturday. This is likely due in part to low temperatures not cooling off much at night, with values forecast to merely drop into the mid to upper 70s each night. WBGTs are also in the upper 80s to around 90 degrees. Therefore, not much relief is in sight, at least through next Saturday. Heat Advisories will likely be issued to account for this heat wave. Make sure to take precautions for the dangerous heat! Wear light- colored loose-fitting clothing, stay hydrated, and take frequent breaks in the shade if you work outside or have outdoor activities! Look before you lock - never leave people or pets in vehicles! && .AVIATION... (00Z TAFS) Issued at 546 PM CDT Sun Jun 28 2026 VFR conditions will persist through the TAF period with light SW winds and a clearing cu field this evening. && .CLIMATE... Issued at 552 PM CDT Sat Jun 27 2026 Moderate Risk for Much Above Normal Temperatures: The Climate Prediction Center has included the Tennessee Valley in a Moderate Risk for Much Above Normal Temperatures on July 5. This means that there is a medium chance (40-60%) for temperatures to reach or exceed 91-94 degrees with heat indices above 105 degrees during this period. More information on the CPC U.S. Hazards Outlook can be found at: https://www.cpc.ncep.noaa.gov/products/predictions/threats/threats.php && .HUN WATCHES/WARNINGS/ADVISORIES... AL...Heat Advisory until 7 PM CDT Tuesday for ALZ001>010-016. TN...Heat Advisory until 7 PM CDT Tuesday for TNZ076-096-097. && $$ NEAR TERM...17 SHORT TERM....17 LONG TERM....26 AVIATION...25