textproduct: Huntsville

KEY MESSAGES

Updated at 123 PM CDT Thu May 21 2026

- There is a low chance of a severe thunderstorm or two on Friday morning into the afternoon hours. The primary hazard is gusty winds and a very low chance of a tornado.

- Beneficial rainfall is expected over the next 7 days with 2-4 inches over this period for most areas. There is a low chance of brief excessive rainfall and minor flooding during this stretch.

- Temperatures remain near seasonal normals for highs and just above for lows.

NEAR TERM

(Tonight) Issued at 123 PM CDT Thu May 21 2026

With even limited daytime heating, SBCAPE values have climbed into the 1500-2000 j/kg range given dew points in the upper 60s to lower 70s. Thus, a few deeper convective cells were developing at this hour over north central and northeast AL. Very low bulk shear values will preclude organization and DCAPE is quite low to due weak lapse rates. The primary hazard will be brief but intense downpours given PW values sitting ~1.8-1.9 inches.

We still expect a decline in precipitation and thunderstorms overnight after loss of daytime heating. However, a new band of showers and thunderstorms associated with the next shortwave will develop in MS tonight and arrive in our western counties toward morning.

SHORT TERM

(Friday through Saturday) Issued at 955 AM CDT Thu May 21 2026

The next wave of showers and thunderstorms will move northeast through the area Friday morning into the early afternoon. CAMS suggest a cellular mode, and given increasing low to mid level winds of 30-40kt, supercells may occur given decent deep layer CAPE values. Thus, SPC has included a marginal risk of severe for Day 2 including a 2% tornado probability.

This will be followed by a similar wave that arrives late Friday night into early Saturday with similar traits. Thus, another round of heavy downpours and gusty winds with the stronger storms is expected late Friday night into Saturday morning. Then, subsidence may quell activity a bit Saturday afternoon and evening. The clouds and precipitation during this period will keep high temperatures in the upper 70s to lower 80s with lows in the 60s. Through Saturday evening, most areas will receive 1-1.75 inches of rain, with locally higher amounts.

LONG TERM

(Saturday night through Wednesday) Issued at 754 PM CDT Wed May 20 2026

A fairly stagnant weather pattern will remain in place late this weekend into the middle of next week. A 5h ridge will be anchored over the southwest Atlantic into GA and FL northwest into the Upper MS valley as a cutoff low in the southern Plains slowly moves northward through the week. The medium range models shows a similar low developing over the southern Plains by mid to late week. However, there is disagreement in the ridge position, the ECMWF is favored here due to its persistence this week. In either case, the pattern will keep persistent deep layer southerly flow in play for the TN valley during this period. This results in medium to high chances of showers and a few thunderstorms will persist Sunday and Monday lowering to low to medium Tuesday and Wednesday, with greatest PoPs during the daytime heating hours into the early evening.

AVIATION

(00Z TAFS) Issued at 638 PM CDT Thu May 21 2026

Multiple rounds of showers and thunderstorms are expected throughout the TAF period. Each round will provide heavy rainfall, brief gusty winds and lightning. CIGS and VIS reductions will create mainly MVFR conditions with IFR conditions more so after sunrise for a few hours. Southerly winds Friday afternoon will gust 15-20kts and will persist til the end of the TAF period.

HUN WATCHES/WARNINGS/ADVISORIES

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