Area Forecast Discussion
Issued by NWS Huntsville, AL
Issued by NWS Huntsville, AL
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
108 FXUS64 KHUN 180746 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 246 AM CDT Sat Jul 18 2026 ...New NEAR TERM... .KEY MESSAGES... Updated at 858 PM CDT Fri Jul 17 2026 - Daily rounds of scattered storms will continue over the weekend into early next week. Strong gusty winds, frequent lightning and very heavy rainfall causing localized flooding may occur. There is a marginal risk of severe storms across far northeast Alabama and adjacent southern middle Tennessee Cumberland Plateau Sunday. - Heat indices will reach the low 100s for many areas west of the Cumberland Plateau into early next week. Tuesday will be the hottest day of the period with heat indices nearing or exceeding 105 degrees for much of the area. - Slightly cooler and less humid air is expected in the middle and latter portions of next week. && .NEAR TERM... (Today) Issued at 246 AM CDT Sat Jul 18 2026 Current satellite shows cloud cover is thinning over the TN Valley and could set the stage for patchy dense fog into the morning hours. Current obs show RH values near 100%, so expect some fog at least around river valleys and areas that have seen recent rain. Lower chances for showers and storms today as the heat cranks up once again bringing heat indices as high as 106 degrees this afternoon. With 105-106 degree heat indices looking more isolated today, will hold off on a Heat Advisory for now but will stress that much of the area is in a Moderate HeatRisk. This will be dangerous for those who are sensitive to heat as well as those who are without proper heating and hydration. Remember to look before you lock and stay weather aware if you have outdoor plans today! Previous discussion: We should have another round of showers and thunderstorms Saturday (mainly in the afternoon). Shower coverage appears will be isolated to scattered, thanks to slightly drier air. As is usually the case, the stronger storms could produce strong gusty winds, frequent lightning, and torrential downpours. Strong heating will push high temperatures into the low/mid 90s, with corresponding heat index values from the upper 90s to 105 degrees. The upper end of this is sufficient for a Heat Advisory; however areal coverage of the hottest values is too isolated to justify putting an Advisory at this time. && .SHORT TERM... (Saturday night through Monday night) Issued at 858 PM CDT Fri Jul 17 2026 Isolated shower/thunderstorm activity should continue Saturday evening. Away from shower activity (most of the area) otherwise will have another muggy, humid night with lows only in the low/mid 70s. A return of higher amounts of moisture, and more strong daytime heating will produce scattered to numerous showers and thunderstorms. Similar conditions are forecast with highs into the lower 90s (with a few mid 90s), and heat index from the upper 90s to 105 degrees. Area coverage of the hottest values may not be sufficient for a Heat Advisory; something we will closely monitor. Shower activity should wind down Sunday night as lows fall into the low/mid 70s. Slightly drier air will reduce rain chances to isolated on Monday. Similar high temperatures should heat again into the low/mid 90s, and lows Monday night in the low/mid 70s. The duration of the heat could become a problem to some, even if conditions do not "officially" reach Advisory criteria. Area residents are urged to exercise caution while outdoors; not limited to drinking plenty of water, limiting your time outside, and trying to stay in the shade as much as possible. && .LONG TERM... (Monday night through Friday) Issued at 858 PM CDT Fri Jul 17 2026 The weather pattern during the day 4-7 period will involve a strong trough developing over the Great Lakes into the mid Atlantic and New England states and an upper ridge building over the southern Plains. A low level thermal ridge (850 mb temps of 20-23C) will arrive on Tuesday, making for a hot and humid day. Heat Risk will reach the Major category (3 out of 4) for much of the TN valley. High temperatures in the lower to middle 90s, heat index values of 100 to ~105F and WBGTs in the middle to upper 80s are expected. A shortwave trough axis and cool front will drop southeast toward the TN Valley through the TN Valley on Wednesday, bringing a low chance of thunderstorms. Behind the front, slightly cooler air with highs in the upper 80s to lower 90s are expected Wednesday, with middle to upper 80s on Thursday after morning lows in the middle to upper 60s. Another Friday morning lows in the 60s, afternoon highs will be near normal and in the upper 80s to around 90. And even better, dew points will drop into the middle to upper 60s Friday. && .AVIATION... (06Z TAFS) Issued at 1244 AM CDT Sat Jul 18 2026 Rain has come to an end across the area and patchy fog will be the main concern through the morning hours. Current satellite shows high clouds overspreading the area that may mitigate a larger fog concern, but trends will be monitored through the morning hours. Low chances for showers and thunderstorms are in the forecast today with the best chances in the afternoon. Reductions to MVFR conditions or lower will occur during any heavier showers/storms. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...None. TN...None. && $$ NEAR TERM...25 SHORT TERM....RSB LONG TERM....17 AVIATION...25