textproduct: Huntsville

KEY MESSAGES

Updated at 1046 AM CDT Fri Mar 13 2026

- A strong cold front will bring a high chance of thunderstorms from late Sunday night-early Monday morning. A medium chance of severe storms will be possible with a primary threat of damaging winds up to 60-70 mph.

- A low chance of a few snow flurries mixed within rain is forecast to occur late Monday morning into the early afternoon, with a hard freeze likely Monday night/Tuesday morning (lows in the lower-mid 20s).

NEAR TERM

(Tonight) Issued at 325 PM CDT Fri Mar 13 2026

Upper level ridging and sfc high pressure continue to allow dry conditions through the Tennessee Valley tonight. Low temperatures are forecast to drop into the 40s tonight under mostly clear skies. A very low chance of patchy fog is possible, primarily along large bodies of water. However, confidence is low at this time due to lack of adequate moisture.

SHORT TERM

(Saturday through Monday) Issued at 1046 AM CDT Fri Mar 13 2026

UPDATE (3/13 Afternoon): SPC has upgraded most of the area to an Enhanced Risk (level 3 of 5) for severe storms Sunday night into Monday morning due to increased confidence in widespread damaging winds.

The primary concern in the short term period will be a deep upper level trough shifting through the southern Plains towards the Tennessee Valley. Associated with this, strong synoptic forcing is likely as there has been model consistency in pushing a ~100-120 kt upper level jet and 70-80 kt LLJ through the Tennessee Valley by Sunday night into Monday morning. As the associated cold front approaches the area, a medium chance of severe storms is forecast. The SPC currently has most of the Tennessee Valley in a Slight Risk (level 2 of 5). The primary hazard with this event will be damaging wind gusts up to 60-70 mph (potentially higher if models remain consistent with the current shear values). While shear is abundant, there continues to be model inconsistency in how much instability will be available to work with. There is some model agreement in timing of the line of storms to move in late Sunday night and exit the area quickly Monday morning (with a few hours of variability). This overnight timing will dampen instability (limiting it to a max of ~200-300 J/kg), keeping the tornado threat low. If timing shifts earlier, the tornado threat will likely increase. The overnight low tornado threat will primarily be fueled by streamwise vorticity that is evident in low levels within model hodographs. As far as hydro concerns go, we are not expecting widespread flooding due to the quick- moving nature of the front (which should be around 50-60 mph). However, with saturated soils, there will likely be some runoff and ponding of water on roadways or areas of poor drainage.

Following the cold front, strong CAA is forecast behind the line of storms. In turn, a few flurries could be mixed in with lingering rainfall late Monday morning in northeastern AL and southern middle TN. No significant accumulations nor impacts are forecast. High temperatures are forecast to top out in the 40s, which is about 15-20 degrees below normal for this time of year. Dry air will take over the region by Monday evening and mostly clear skies should return. Monday night, we will be monitoring for record breaking lows as temperatures drop into the low to mid 20s. The record for HSV is 21 degrees (1956) and the record for MSL is 20 degrees (1916). Additional details in the long term section below.

LONG TERM

(Monday through Thursday) Issued at 1142 PM CDT Thu Mar 12 2026

Low clouds and potential flurries will persist early Monday morning, but should end by midday. But blustery and very cold air will continue to advect into the region. 8h temperatures will fall to -8 to -10C by late afternoon and evening. High temperatures once low clouds dissipate will only rise into the middle to upper 40s. A hard freeze is forecast Monday night into Tuesday morning as a ridge of high pressure along the MS River begins to shift into the TN Valley. Tuesday morning lows will easily drop into the lower to middle 20s. After highs again in the 40s Tuesday, overnight lows will drop into the upper 20s to around 30.

Northwesterly 5h flow will persist through Wednesday and Thursday as an anomalous 5h anticyclone of 594dkm takes shape over AZ. A large and warm thermal ridge will result over the Rockies into the Plains, advecting into the OH and TN valleys Wednesday into Thursday. This will result in a significant warmup with highs in the 50s Wednesday and 60s on Thursday. Isentropic lift/warm air advection will generate mainly mid and high level clouds Wednesday night into Thursday. At this time, no precipitation is foreseen, but will monitor that trend in coming days as Gulf moisture return can better be assessed.

AVIATION

(18Z TAFS) Issued at 1203 PM CDT Fri Mar 13 2026

VFR conditions are forecast through the TAF period at both KMSL and KHSV. Southwesterly wind gusts up to 17 kts should continue through the afternoon before subsiding this evening.

HUN WATCHES/WARNINGS/ADVISORIES

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