textproduct: Huntsville

KEY MESSAGES

Issued at 323 AM CDT Wed May 20 2026

- Medium to high chances (60-90%) of showers and thunderstorms are forecast today through early next week. No severe weather is forecast.

- Locally heavy downpours and frequent lightning may accompany all thunderstorms and those with outdoors plans or events should monitor the forecast.

NEAR TERM

(Today) Issued at 323 AM CDT Wed May 20 2026

A broad area of showers and a few embedded thunderstorms continue to meander across northern Mississippi. This activity has drifted largely NNE into western Tennessee and has remained just west of the region. Overall, this activity has diminished over the course of the night, but would not be shocked if a few light showers (and maybe an elevated thunderstorm) clip portions of far northwest Alabama near the AL/MS border between 09-12z. The latest trend in guidance is for this overnight activity to dissipate late this morning. However, would expect some regeneration late this morning and into the afternoon hours as a weak front pushes into the Tennessee Valley. Despite the cloud cover, some partial heating in the morning hours will allow for some appreciable destabilization of the boundary layer by this afternoon -- with medium to high (60-90%) chances of showers and thunderstorms forecast during this afternoon timeframe. PWATs in the 85-90th percentile for this day will help make any convection that can develop capable of producing locally heavy rainfall. The dense cloud cover and higher rain chances will keep highs a few degrees lower, with highs peaking in the low to mid 80s.

SHORT TERM

(Wednesday night through Friday night) Issued at 1035 PM CDT Tue May 19 2026

With weak shear remaining over the area near the front on Wednesday night and the loss of daytime heating, coverage should drop off significantly to low to medium coverage (20-50%). However, we will remain in a humid airmass, as the front moves north again into Thursday. This will keep overnight lows on the warm side Wednesday night, only dropping into the lower to mid 60s.

As the front moves northward again on Thursday, additional shortwaves move along it. Combined with building instability as the front moves back over the area, widespread showers and thunderstorms are expected to develop (especially in the afternoon). Shear remains weak in most model output (less than 25 knots). That is a good thing given instability shown by guidance (1500-3000 J/KG). PWATS increase again though, so heavy downpours and frequent lightning will be fairly common. We will need to monitor for minor flash flooding issues Thursday afternoon.

Things don't change through Friday, as the front doesn't move much and additional disturbances move along it through the area. This will keep highs Friday afternoon in the lower to mid 80s. There might be a bit stronger shear (0-3 km ~ 30 knots) Friday afternoon along with instability between 1000 and 3000 J/KG, just enough shear to have to worry about strong to marginally severe thunderstorm activity. Some minor flash flooding could occur on Friday as well. Overnight lows Thursday night will push higher into the mid to upper 60s.

LONG TERM

(Saturday through Tuesday) Issued at 1035 PM CDT Tue May 19 2026

Southwesterly flow will largely persist aloft through the long term period. In addition, a series of shortwaves looks to ripple across the Southeast during the weekend and into early next week. At the surface, a cold front is slated to slowly make its way towards the Southeast through the weekend, but stall over the mid-Mississippi Valley and into the lower Ohio Valley early next week. This pattern will maintain low-level southerly flow over the region as well the continued advection of moisture up from the Gulf. Therefore, the rainy and summertime-like pattern is expected to continue through at least early next week, with daily chances (50-80%) of showers and thunderstorms. Highs will be temperated a bit by the higher rain chances each day; but, highs are forecast to generally reach the lower to mid 80s with lows in the 60s.

Model PWATs generally remain between 1.6-1.8 inches throughout the period, which are over the 90th percentile when compared with Sounding Climatology from Birmingham (~1.6 inches) for May 23rd through 26th. Showers/storms will therefore be efficient rainfall producers, so we'll need to monitor for the increased risk of localized flooding for areas that receive rainfall repeatedly. As for the potential for any severe weather, guidance suggests that bulk shear values may reach around 30 knots periodically this weekend and into early next week. Therefore, there is a non-zero chance of a stronger storm or two, but confidence is low at this point. Regardless, if you have outdoor plans, make sure to stay weather aware, as lightning is dangerous whether or not a storm is severe! In addition, if you encounter any flooded roads, remember to Turn Around, Don't Drown!

AVIATION

(12Z TAFS) Issued at 549 AM CDT Wed May 20 2026

VFR conditions will prevail at both terminals early this morning, before clouds increase and ceilings drop late this morning into the afternoon. A front will move into the region, bringing medium to high chances of showers and storms. Have added a TEMPO during the main window of TSRA activity (20-00z). AWWs and amendments may be needed during this timeframe. After sunset, MVFR conditions will develop as low stratus settles in after convection wanes.

HUN WATCHES/WARNINGS/ADVISORIES

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