textproduct: Huntsville

KEY MESSAGES

Updated at 1012 AM CDT Sun Jul 19 2026

- Moderate (Level 2/4) to Major (Level 3/4) Heat Risk will build into the Tennessee Valley through the middle of next week, with peak heat index values between 100 to 105 degrees likely, and potentially between 105-109 degrees in some locations Monday and Tuesday.

- Daily thunderstorm chances will continue into early next week. A few storms could become strong to marginally severe today. Gusty to damaging winds, frequent lightning, and locally heavy rainfall will be the main threats.

NEAR TERM

(Tonight) Issued at 202 PM CDT Sun Jul 19 2026

Looks like the morning convection did not hinder the development of afternoon convection much at all. Numerous showers and storms are ongoing over north-central and northeast Alabama as well as southern middle Tennessee. Most of the storms have been sub- severe, but we have been monitoring a few storms that have had decent cores to them. Expecting this activity to persist through the afternoon (and likely fill in over NW AL) and into this evening. The low chance of severe storms remains, with damaging winds, frequent lightning, and heavy downpours the main threats. Small hail may also occur, but not anticipating large hail due to the amount of moisture in the atmosphere at the moment as well as the freezing level being high (~16kft). Make sure to stay weather aware and when thunder roars, go indoors! Have multiple ways to receive warnings! This activity has also dampened the heat, so not expecting Heat Advisory criteria to be met (or even approached) today. Current temperatures are merely in the 80s at present.

Showers and storms will diminish through mid to late evening, with no rain forecast late tonight into early Monday morning. However, as previously stated, we'll need to monitor for at least patchy fog for much of the local area late tonight due to calm winds, low dew point depressions, and potential breaks in clouds.

SHORT TERM

(Monday through Tuesday) Issued at 1012 AM CDT Sun Jul 19 2026

Upper level ridging over the central US tries to build southeast into the region, but the tropical system currently over the eastern Gulf looks to meander to the west along the northern Gulf coast through midweek. This may prevent the ridge from building into our area quite as much. Although, high pressure is slated to develop over the Appalachians once the aforementioned surface front pushes back north as a warm front Monday night. Even so, humidity will remain elevated through early next week. Low to medium shower and storm chances (20-40%) on Monday look to decrease by Tuesday to be mainly low (10-30%, highest over NE AL and TN counties). SPC did clip the northeast portion of the local area in a Marginal Risk of severe weather on Tuesday; however, current thinking is that most of the storm activity will be concentrated to our northeast. So, confidence is low on any severe weather on Tuesday.

The main concern will continue to be the heat as high humidity persists and highs are expected to reach the lower to mid 90s with lows in the lower to mid 70s (approaching upper 70s in some locations) Monday and Tuesday. Much like today (Sunday), uncertainty remains in whether shower and storm activity will dampen heat a bit on Monday. However, heat index values may reach the 100-107 degree range once again on Monday with a Moderate HeatRisk (level 2 of 4) and WBGTs in the mid to upper 80s. With lower coverage of showers/storms anticipated on Tuesday, the forecast continues to pinpoint that this day will be the hottest of the week with heat indices in the 102-109 degree range, along with a Major HeatRisk (level 3 of 4) and WBGTs in the upper 80s to around 90 degrees in some spots. A Heat Advisory for Tuesday will likely be needed for all of north Alabama and southern middle Tennessee in subsequent updates. Stay hydrated, take frequent breaks in the shade, and never leave people or pets in vehicles!

LONG TERM

(Tuesday night through Saturday) Issued at 854 PM CDT Sat Jul 18 2026

A strong mean upper trough position will remain in place over the Great Lakes into the northeast U.S. late next week into the weekend while an upper ridge sits over the Southern High Plains. This will keep a robust northwest flow pattern from the northern Plains and Corn belt into the central Appalachians. The good news for the local area is that a cold front will arrive on Wednesday. This will bring chances of showers and thunderstorms before delivering noticeably drier air into the region, at least for a couple of days with dew points dropping into the 60s. Highs will be in the middle to upper 80s Thursday, followed by low temperatures in the 60s. By next weekend, "ridge rider" MCSs may start to clip our area with low chances of thunderstorms introduced into the forecast Friday night into Saturday. The risk of some severe weather will have to be monitored in this pattern with increasing shear and strong instability.

AVIATION

(18Z TAFS) Issued at 1228 PM CDT Sun Jul 19 2026

VFR conditions will prevail through late this evening. The exception to this will where storms move over this afternoon, bringing the potential for lower CIGs and VIS. Gusty winds, frequent lightning, and heavy downpours are also anticipated in the stronger storms. Activity should wane through this evening, with no rain overnight. What we'll need to watch tonight is fog development. Expecting at least MVFR conditions later tonight at both terminals, with instances of IFR as well (such as at HSV). This will be monitored for further reductions, especially if dense fog forms. Any fog should then lift and dissipate through mid- morning on Monday. Otherwise, expect winds less than 10 knots (outside of storms) this afternoon to decrease to be calm this evening.

HUN WATCHES/WARNINGS/ADVISORIES

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