textproduct: Huntsville

KEY MESSAGES

Updated at 1235 AM CDT Sat Jun 21 2026

- Low chances (30% or less) of showers and thunderstorms are forecast this evening before rain chances increase to between 30-70% after midnight. - Medium-high chances (60-90%) of thunderstorms are forecast Monday and Tuesday- peaking during the afternoon hours. A few storms have a low chance of becoming severe on Monday, with damaging winds and localized flash flooding being the main concerns

- Low-medium chances (40% or less) for showers and thunderstorms will continue Tuesday night-Saturday, but storm coverage across our region will depend on the location of a weak stationary front

NEAR TERM

(Today) Issued at 303 AM CDT Sun Jun 21 2026

Low level cloud development has helped limit fog formation across much of northern Alabama over the last few hours. The exception to this is from the Muscle Shoals area east along the Tennessee River into western Madison county. In those areas, fog formation (some locally dense) will continue to be possible for a few more hours. However, around 5 or 6 AM, models hint that even these areas will fill in with low clouds. Expect these clouds to linger into the late morning hours.

Guidance continues to back off on rain or storms forming over northern Alabama today. They continue to focus precipitation along a more distinct area of convergence over southeastern Alabama extending into SE Georgia. We should see cloud cover break up towards noon. Sunshine should help push high temperatures into the 85 to 90 degree range. It will be very humid pushing heat index values into the mid to upper 90s in a few locations, so if working outside give yourself plenty of breaks and stay hydrated.

SHORT TERM

(Tonight through Tuesday) Issued at 958 PM CDT Sat Jun 20 2026

Rain chances increase late this evening into Monday morning (30-70%) as an upper level shortwave shifts east into the area once again. Simultaneously, an approaching cold front stemming from low pressure centered over the OH River Valley will force high chances (70-90%) of thunderstorms by Monday afternoon. Model soundings indicate PWATs reaching around 1.9-2.2", which is above the 90th percentile per BMX and OHX sounding climatology. Therefore, thunderstorms will be efficient rainfall producers. Additionally, Corfidi upshear values indicate the potential for backbuilding/training of relatively slow moving storms, increasing the overall flash flood threat. The Weather Prediction Center has outlooked our area in a Slight (risk level 2 of 4) outlook for Excessive Rainfall Monday morning through Tuesday morning. A secondary threat will be damaging winds as both instability as well as shear will support some organized convection. The Storm Prediction Center has outlooked the entire Tennessee Valley in a Marginal Risk (level 1 of 5) for severe weather. Be sure to have multiple ways to get warnings Monday as multiple threats are on the table. Another heat threat also exists Monday afternoon as highs are forecast to reach the upper 80s once again with heat indices in the upper 90s to around 100, however, we will be monitoring how thunderstorms and subsequent cloud cover affects these temperatures as they will likely be cooler than currently forecast. While rain chances decrease overnight, medium rain chances (40-60%) return Tuesday afternoon as a boundary stalls to our south. This will continue a low flooding threat in NW AL, where the Weather Prediction Center currently has us outlooked in a Marginal Risk (level 1 of 4) for Excessive Rainfall. We encourage everyone with plans early in the week to remain weather aware and check back in for updates.

LONG TERM

(Tuesday night through Saturday) Issued at 958 PM CDT Sat Jun 20 2026

For the first couple of days of the extended period (Wednesday/Thursday), our forecast area will remain beneath a light (10-20 knot) NW flow aloft between a strong subtropical high centered across southern AZ/southern NM/northern Mexico and an amplifying northern stream shortwave trough digging southeastward into the Great Lakes. In the low-levels, high pressure (initially across the central Appalachians) will shift quickly eastward off the Mid- Atlantic Coast as a slow-moving area of low pressure drifts southeastward across the Upper MS Valley/Great Lakes. This will yield light SSW return flow across our region (perhaps as early as Wednesday, but more likely by Wednesday night) which will contribute to an increase in the coverage of showers/thunderstorms once again. Present indications are that storm coverage will remain fairly high on Thursday to the south of a weak cold front trailing southwestward off the low to our north, but deep-layer flow and shear appear too weak to warrant concern for organized convection. Nevertheless, a moist/unstable airmass featuring PWAT values of 1.6-1.8" and CAPE of 1500-2500 J/kg could result in a risk for strong downburst winds.

During the timeframe from Friday-Saturday, global models suggest that the mid-level high over the southwestern deserts will begin to weaken as the central North Atlantic subtropical ridge strengthens and retrogrades westward across the FL Peninsula and into the eastern Gulf. With our region likely to become increasingly influenced by minor height rises aloft and drying profiles, we expect the coverage of showers and thunderstorms to gradually decrease from Friday into Saturday (although with a lingering front/convergence axis likely to lie somewhere in the vicinity of the TN Valley, rain chances will certainly be non-zero). Highs will progressively warm from the l-m 80s into the m-u 80s by Saturday, as overnight lows rise from the m-u 60s into the u60s-l70s.

AVIATION

(06Z TAFS) Issued at 1235 AM CDT Sun Jun 21 2026

VFR conditions are currently in place at both terminals. Clear skies are currently in place as well. Winds are light and variable and should remain so through 13Z or 14Z. Dewpoint depressions are already 1 degree or less, so fog development will likely occur shortly after 5Z or 6Z. There is some question if low cloud cover will develop northward towards the terminals. However, believe between 6Z and 8Z we will start to see visibilities drop before cloud cover can build in. Due to the question of cloud development, kept drops in visibility somewhat conservative. At KMSL, dropped VSBYS to 5SM by 8Z and included a tempo between 9Z and 13Z with IFR VSBYS down to 2 SM. Further east at KHSV, cloud cover may develop later, thus dropped vsbys a bit lower (after 8Z dropped VSBY to 3SM and included a tempo between 9Z and 13Z for lower IFR VSBY down to 1 SM). VFR conditions should return after 13Z.

HUN WATCHES/WARNINGS/ADVISORIES

AL...None. TN...None.