textproduct: Huntsville

KEY MESSAGES

Updated at 1109 AM CDT Mon Jun 8 2026

- Excessive rainfall and life-threatening flash flood risk will persist through Tuesday.

- A Flood Watch is in effect until 8 PM today for much of north AL and all of southern middle TN.

- Heat Risk increases by late this week. Heat index values in the middle 90s to around 100 degrees Wednesday through Saturday.

NEAR TERM

(Tonight) Issued at 358 PM CDT Mon Jun 8 2026

Recent radar and satellite trends show that convection along the I-20 corridor has resulted in a northward-moving outflow boundary that is now serving as the forcing mechanism for additional convective initiation south of the TN River. Thunderstorms have increased along this boundary, and additional development is expected through the afternoon as the boundary continues to move north through the area. Farther west, a cluster of thunderstorms continues to move eastward across northeast MS. While recent high- res guidance suggests these storms may struggle to maintain organization as they move into the TN Valley, the thermodynamic environment remains highly favorable for heavy rainfall production. Sfc based CAPE values approaching 4000 J/kg combined with PWATs exceeding 2.2" will support the potential for very high rainfall rates within any sustained convection.

The greatest concern will be in areas where low level convergence becomes enhanced along these outflow boundaries and may be a focus for repeated thunderstorm development. This would result in training or slow-moving storms that will be capable of producing excessive rainfall in a short amount of time. Given the saturated soils and ongoing flooding from yesterday's rainfall, it will take very little rain to produce rapid runoff resulting in additional flash flooding.

Trends will continue to be monitored closely through the afternoon. Residents across the Tennessee Valley should remain weather aware throughout the day and treat all Flash Flood Warnings as life-threatening situations. Use extreme caution if driving through rainfall, obey all road closures, and never attempt to drive through flooded roadways!

Rain should come to an end from west to east late this evening with a brief period of dry conditions before low rain chances start to creep back in across norther portions of the forecast area before sunrise. Please remember that any areas that flood today will likely remain that way overnight, leading to an increased threat to life due to lower visibility.

SHORT TERM

(Tuesday through Wednesday) Issued at 1109 AM CDT Mon Jun 8 2026

The aforementioned upper trough axis will begin to shift east of the area on Tuesday, resulting in low to medium chances for showers and storms particularly for areas east of I-65. With PWATs still near 2", additional heavy rainfall could worsen flood conditions. Due to the more scattered nature of these storms, the Flood Watch was not extended through Tuesday at this time but forecast trends will be monitored closely. Convection will become more diurnally driven during the mid-week period with rain chances capping near 30% Wednesday afternoon. The threat will begin to shift more toward dangerous heat during this time with afternoon heat indices approaching 100 degrees. Be sure to keep heat safety in mind for any outdoor plans later this week!

LONG TERM

(Wednesday night through Sunday) Issued at 1209 AM CDT Mon Jun 8 2026

The ridge across much of the southern and eastern CONUS will be dampened as a wave of energy rounds the base of a trough in southern Canada on Thursday and furthermore on Friday. On Friday, the associated sfc low will be north of the Great Lakes, but the cold front will drape down through the OH Valley and back into the Mid MS Valley. Some models have the cold front dipping toes into the TN Valley Friday night, while others are suggesting it stalls out north of us and never makes it in. Will stick with guidance for now with this, and that brings a medium chance (60%) of showers and thunderstorms Friday. Otherwise, we will be under high pressure throughout the rest of the extended forecast, but it won't feel like it. We'll be trapped in with plenty of moisture for diurnally driven convection each day (low to medium chances 20-50%).

We will also turn up the heat as temps reach the upper 80s/lower 90s on Thursday through Saturday and just in the upper 80s on Sunday. It is important to note that this set up will also push the heat index values into the upper 90s/lower 100s Thursday through Saturday. Will monitor trends, but right now values are below Heat Advisory Criteria. Regardless though, you will need to practice heat safety because we do not feel acclimated to the high heat and humidity for this long quite yet, so ensure that you stay hydrated and slow down to prevent heat related illnesses.

AVIATION

(00Z TAFS) Issued at 619 PM CDT Mon Jun 8 2026

VFR to MVFR conditions are forecast through the TAF period with periods of lowered visibility and ceilings with thunderstorms pushing northward. AWWs are likely at KHSV through this evening.

HUN WATCHES/WARNINGS/ADVISORIES

AL...Flood Watch until 8 PM CDT this evening for ALZ001-005>010-016.

TN...Flood Watch until 8 PM CDT this evening for TNZ076-096-097.