textproduct: Huntsville

KEY MESSAGES

Updated at 1109 PM CDT Sun Jul 26 2026

- A Heat Advisory remains in effect for areas along and west of I-65 through 7 PM Tuesday.

- Clusters of thunderstorms will shift southward during the early morning hours Monday, with potential redevelopment of storms in the southwest during the afternoon. Locally damaging winds, frequent lightning and heavy rainfall will accompany this activity.

- A cold front will bring additional thunderstorms to the region Tuesday afternoon/evening, with coverage highest in the east. A a few strong-severe storms may occur during this timeframe.

- A drier airmass will encompass the region from Wednesday- Friday, but chances for showers and some thunderstorms will increase once again this weekend.

NEAR TERM

(Today) Issued at 200 AM CDT Mon Jul 27 2026

The MCS that moved in around 4Z has largely died with light stratiform rain remaining. Unfortunately, remnant outflow boundaries and another passing short wave have fired off another mass of storms currently moving into TN. CAMs remain an absolute mess, thus this forecast is largely based off of radar, observations site, and satellite trends. Current thinking is this second wave of storms will make it into the area around sunrise but be significantly weaker and pose little to no severe threat. Showers and storms will likely dissipate through mid morning with a decent amount of cloud cover lingering through around 16Z. Beyond that, conditions should quickly heat up. With high 70s to low 80s dew points in place it won't take much to push heat indices into the triple digits with seeing heat index values above 105 likely across the area. As such, a Heat Advisory remains in effect for portions of north Alabama and southern middle TN.

As for storm chances tomorrow afternoon, it will again be contingent on what happens upstream. With CAMs verifying horribly today, it's hard to place any value in their output. Rather, we will watch radar and satellite trends through the afternoon to assess additional storm development and possible threats to our area. Please check back for updates as this pattern has allowed MCSs to spin up quite quickly, which subsequently has significant impacts to our forecast.

SHORT TERM

(Monday night through Wednesday) Issued at 1109 PM CDT Sun Jul 26 2026

Over the course of the short term period, an intensifying mid- level shortwave trough in the northern stream is predicted to travel across the eastern Great Lakes before evolving into a closed low over the northern Mid-Atlantic states that will drift slowly east-southeastward through Wednesday. In the low-levels, a surface low related to the shortwave trough is expected to gradually deepen across NY/PA, with a cold front attached to the low expected to make steady southeastward progress on Monday night and Tuesday. Southwesterly flow in the low-levels will begin to strengthen on Monday night, and although latest guidance from the CAMs indicates that another MCS will track south-southeastward from the Lower Great Lakes into eastern KY/TN, at this point it appears as if this system will bypass our forecast area to the northeast.

However, chances for thunderstorms should begin to increase in our CWFA by mid/late Tuesday afternoon (and continue through the evening hours) as a prefrontal trough/wind shift axis begins to enter the region from the north. Although the coverage of convection should be higher to our north/east (where deep-layer ascent will be augmented by the shortwave trough), it seems reasonable to believe that at least scattered storms will develop as far southwest as northern AL. Very hot temperatures (m-u 90s) and high dewpoints (u70s-l80s) will exist ahead of the wind shift axis, warranting another Heat Advisory and yielding high CAPE of 3000-3500 J/kg. This level of instability, coupled with an increase in NNW flow aloft to 20-30 knots, suggests that damaging winds and frequent lightning will be possible with the strongest cells. Light northerly flow in the wake of the front will begin to advect a drier continental airmass into the region during the day on Wednesday, with only a low chance for a few showers south of the TN River before this occurs.

LONG TERM

(Wednesday night through Sunday) Issued at 1109 PM CDT Sun Jul 26 2026

Extended range guidance from the lastest suite of global models continues to indicate that our forecast area will remain under the influence of moderately strong NNW flow aloft and dry northerly flow at the surface from Wednesday night-Friday. With dewpoints falling into the 60s, overnight lows will respond by dropping to more comfortable levels (m-u 60s), with afternoon highs remaining in the u80s-l90s. However, it appears as if deep-layer moisture will quickly return to the region at some point Friday night/Saturday morning as a compact surface low shifts eastward from the southern Plains into the Lower-MS Valley. Although strong low-level warm/moist advection ahead of the low will contribute to an increase in the coverage of convection across our region, current thinking is that instability will remain low (at least compared to the past couple of weeks) and should limit the overall coverage of thunderstorms. That said, the low-level jet will likely increase considerably ahead of this system, and may yield at least a limited risk for storm organization on Friday night/Saturday. By Sunday, the surface low is expected to weaken and transition into a broad trough across the Gulf Coast states, which should lead to a gradual decrease in the coverage of precipitation across our region.

AVIATION

(12Z TAFS) Issued at 543 AM CDT Mon Jul 27 2026

Rain and the potential for lower ceilings look to continue for a few hours past sunrise at HSV. Around 14Z rain looks to dissipate with clouds clearing through the morning. VFR conditions should be in place by mid day. There is a low chance of more convection in the second half of the TAF period but confidence is currently too low to include it.

HUN WATCHES/WARNINGS/ADVISORIES

AL...Heat Advisory until 7 PM CDT Tuesday for ALZ001>007-016.

TN...Heat Advisory until 7 PM CDT Tuesday for TNZ076-096.