449 FXUS64 KHUN 262324 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 624 PM CDT Sat Jul 26 2025 ...New AVIATION... .NEAR TERM... (Tonight) Issued at 239 PM CDT Sat Jul 26 2025 Under partly cloudy skies temperatures have risen into the high 80s to low 90s across the area. Along the western periphery of high pressure, continued SW flow is supporting scattered showers and a few thunderstorms across the area. These will continue to move south to north over the next several hours and wane just after sunset yielding a mostly clear night. Despite clear and calm conditions, overnight lows will only drop into the mid 70s before another hot and humid day tomorrow. && .SHORT TERM... (Sunday through Tuesday) Issued at 1055 AM CDT Sat Jul 26 2025 Through the short term forecast, ridging will continue to build and anchor itself over the TN Valley. At the surface this will amount to a significant warming trend in both our temperatures and heat indexes through mid week. Temps look to rise from the low 90s on Sunday to the high 90s on Tuesday. These temps couples with dew points in the mid to high 70s will amount to heat indexes also increasing steadily through mid week. Values look to increase from 100-105 on Sunday to 105-110+ by Tuesday. We have rather high confidence in seeing these values as long range models have been hinting at this pattern for over a week and probabilities of seeing 100-105+ heat indexes continue to increase in the LREF and NBM. With that being said, Heat Products will be needed for a majority of the area through mid week. For this forecast update, a Heat Advisory has been issued for NW and north central Alabama along with Lincoln and Moore counties in southern middle TN from 11 AM to 9 PM tomorrow on Sunday. While we look to meet Heat Advisory Criteria again through the start of the week, we will postpone issuing additional products until tomorrow to allow for more in depth analysis of HIRES model guidance to aid in differentiating who will see a Heat Advisory and who will see an Extreme Heat Warning through mid week. Currently NW AL looks most favorable to see and Extreme Heat Warning. Regardless of the exact products issued, it will be incredibly important to continue to practice proper heat and sun safety through the week. We will be in major heat risk for the entire area through mid week meaning this level of heat will impact anyone and everyone without proper heating and hydration and could result in a strain on health care services and our cooling infrastructure. Make sure to have a plan for you and your loved ones including pets for dealing with the heat. && .LONG TERM... (Tuesday through Saturday) Issued at 920 PM CDT Fri Jul 25 2025 Upper level ridging will strengthen over the Southeast and Mississippi Valley on Tuesday, then stretch westward over the Plains by midweek. From Wednesday through Friday, an upper trough over eastern Canada will dive southeast over the northeastern U.S., shifting the greater influence of the ridge over the central CONUS. At the surface, high pressure looks to persist over the Appalachians until a surface front traverses the Midwest and Ohio Valley by Wednesday. This feature is shown to then gradually make its way south, progressing over the Tennessee Valley Thursday into Friday. Thus, very hot conditions (the hottest of the year so far) will comprise the first half of the long term period, with higher shower/storm chances and somewhat cooler conditions to follow by late week. As moisture remains elevated for the region through the period, this combined with forecast highs in the mid to upper 90s will lead to very hot conditions Tuesday and Wednesday. In fact, it will be the hottest heat wave we`ve seen so far thus summer, as heat indices are expected to reach between 105-115 degrees! Yes, it`s summer and it`s hot during the summer. However, to put it into perspective a little bit: in Huntsville so far this July there has only been one day with high temperatures below 90 degrees and 18 days with heat indices at or above 100 degrees. Yes, it is hot, but Tuesday and Wednesday will be exceptionally hot. Criteria for an Extreme Heat Warning requires heat indices at or above 110 degrees or air temperatures greater than 105 degrees. Therefore, as has been the trend the past couple of days, it`s looking more and more likely that we will meet this criteria with our forecast heat index values. That being said, heat products will be necessary in the coming days to account for this. So, what can you do to be safe in this extreme heat? Make sure to drink plenty of water, take frequent breaks in the shade, wear light- colored and light-weight clothing, and never leave people or pets in vehicles! As we move into the latter half of the week, the aforementioned upper trough and surface front will bring much needed relief from the oppressive heat. Highs are expected to "cool" into the upper 80s to lower 90s by Friday along with increased shower and storm chances both Thursday and Friday. At this time, severe weather is not anticipated, but any storm that becomes strong will be capable of producing gusty winds, heavy downpours, and frequent lightning. For those working outside or have outdoor activities, remember: when thunder roars, go indoors! && .AVIATION... (00Z TAFS) Issued at 624 PM CDT Sat Jul 26 2025 Shower and storm activity to our southwest continues to gradually make its way towards north Alabama late this afternoon; however, much of the activity has seemed to dwindle as it gets close. Regardless, low chances (10-30%) of showers and storms will continue for the next couple of hours then decrease through the evening hours. No showers or storms are then forecast overnight. While patchy river valley fog is possible later tonight, not currently thinking the terminals will be impacted. Another hot day with low (10-30%) chances of showers and storms is on tap for Sunday. Storms will be capable of heavy downpours, some gusty winds, and lightning and may also bring brief periods of lower CIGs and VIS to the terminals should any storms move over them. Outside of any storms, light and variable winds tonight will become westerly at around 5 knots or so by early Sunday afternoon. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...Heat Advisory from 11 AM to 9 PM CDT Sunday for ALZ001>008-016. TN...Heat Advisory from 11 AM to 9 PM CDT Sunday for TNZ076-096. && $$ NEAR TERM...RAD SHORT TERM....RAD LONG TERM....26 AVIATION...26