textproduct: Huntsville

KEY MESSAGES

Updated at 1015 PM CDT Mon Apr 27 2026

- Low chance for severe thunderstorms tonight into early Tuesday morning, especially in NW Alabama. Further east, this threat will linger until just before daybreak on Tuesday. - Low chance of severe thunderstorms Tuesday evening into Tuesday night.

- Rainfall totals of 1.5 to 2.5 inches are forecast through Wednesday. Another solid half of an inch to an inch is forecast Thursday through Friday.

NEAR TERM

(Rest of tonight and Tuesday) Issued at 1015 PM CDT Mon Apr 27 2026

A low-end threat for strong to severe storms will continue overnight across North Alabama and Southern Middle TN as discrete convection has developed over northern MS ahead of an approaching system. High-res guidance continues to show some variability regarding the strength of a capping inversion around 3km, noted in the earlier 12z observed soundings from BMX and OHX. Recent ACARs soundings suggest near sfc temps may have warmed enough in some locations to erode this cap and allow for more robust storm development, but this threat seems a bit overdone based on current satellite and sounding observations. Taking a look at the recent 00z OHX and BMX soundings, capping in the 1-3km layer will likely win out over northern AL for the most part until the stronger forcing for ascent arrives later tonight. With that said, convective trends over northern MS will still need to be monitored closely over the next several hours, and SPC has issued a Tornado Watch over far NW AL to cover the threat both for any discrete supercells over the next several hours as well as along the eventual convective line of storms expected during the early morning hours.

While stronger large-scale forcing remains displaced to our north and west limiting convective coverage for much of the evening, taller updrafts have developed over northern MS over the past hour and have become strong enough to produce frequent lightning and quarter sized hail. So far, convective attempts closer to the AL/MS state line have not been sustainable where storms over NW MS have had better longevity. Given the favorable thermodynamic and increasingly favorable kinematic environment in place, any storms that form and are rooted at the sfc and remain discrete may quickly become supercellular and will be capable of producing all severe hazards, including damaging winds, large hail, and tornadoes.

The more likely severe threat for especially NW AL will arrive during the early morning hours as semi-discrete convection currently over southern Missouri gradually congeals into an MCS and tracks southeast through western and central TN before moving into the area. As this complex evolves, the primary hazard will transition more toward damaging straight-line winds, though embedded circulations capable of producing a tornado will be a key concern, especially along any bowing segments within the leading edge of the line.

With the threat expected to persist through the overnight hours, residents should ensure they have multiple reliable ways to receive warning information, especially methods capable of waking them up while sleeping.

SHORT TERM

(Tuesday night through Thursday) Issued at 1015 PM CDT Mon Apr 27 2026

The main focus during the short term period will be another round of strong to severe thunderstorms tomorrow evening into early Wednesday morning as a mid/upper lvl shortwave moves eastward above a warm and unstable airmass across much of the ArkLaMiss into TN Valley region. Southerly flow through the day will allow temps to warm into the upper 70s/lower 80s while maintaining rich low-level moisture, resulting in moderate to strong instability by late afternoon and evening. While overnight convection should limit activity through the morning and early afternoon hours across the TN Valley, large scale ascent should result in an uptick in discrete storms/clusters east of a dryline feature across portions of the southeastern Great Plains tomorrow afternoon before tracking into the Deep South tomorrow evening.

There remains some uncertainty regarding convective evolution, particularly as the progression and eventual impacts of tonight's storms may influence mesoscale boundaries, instability recovery, and storm mode as we head through Tuesday. Remnant outflow boundaries and any lingering convection could alter where the greatest severe threat ultimately develops and may result in adjustments to timing and the placement of the highest severe threat in later forecasts.

Forecast guidance continues to suggest an environment supportive of organized severe storms, with sufficient deep-layer shear to support both supercells and eventual upscale growth into clusters or a line/MCS of storms overnight. Discrete storms that can develop ahead of the main MCS would pose the greatest threat for all severe hazards with a conditional risk for a few stronger tornadoes if sustained supercells can be realized. If the current model trends hold, the primary hazard may shift toward damaging straight-line winds with the overnight MCS, though embedded circulations may form within any bowing segments along the line. Locally heavy rainfall and frequent lightning will also accompany stronger storms.

The severe threat is expected to gradually diminish from west to east during the early morning hours Wednesday as storms encounter weaker instability. Residents should continue to monitor later forecasts and ensure they have multiple reliable ways to receive warnings, especially with storms expected during the overnight period. A cold front is progged to move through the area Wednesday afternoon, and cooler temps with low chances for rain will linger through Thursday.

LONG TERM

(Thursday night through Monday) Issued at 1015 PM CDT Mon Apr 27 2026

Models are in agreement that an upper level trough will likely shift southeastward into the area this weekend, placing the TN Valley in a favorable location for additional chances for rainfall. At this point, ensembles depict a fairly stable environment with plenty of CIN and weak lapse rates. Therefore, confidence in any stronger storms remains extremely low for now. PWATs are forecast to be around 1" Friday night into Saturday morning, which is on par with climatological normals for this time of year. However, with the antecedent rainfall this week, we will have to monitor for rises on rivers, creeks, and streams as well as ponding of water in areas of poor drainage. Conditions should begin to dry out Saturday afternoon with upper level ridging and sfc high pressure filtering in from the west. We should remain dry through early next week with highs in the 60s-70s.

AVIATION

(06Z TAFS) Issued at 101 AM CDT Tue Apr 28 2026

VFR conditions will persist through the early overnight hours before a line of storms moves into the area later this morning. Gusty winds and hail will be the primary concerns with this first line of storms where reductions to IFR or LIFR conditions will be likely within heavier convective storms. Will likely see a break in thunderstorm activity during the late morning to early afternoon hours before additional rounds of storms move into the area later in the afternoon through the early overnight hours. Adjustments to the TAFs will likely be made, especially during the morning to early afternoon hours as the convective environment evolves.

HUN WATCHES/WARNINGS/ADVISORIES

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