textproduct: Huntsville

KEY MESSAGES

Updated at 1209 AM CDT Mon Jun 8 2026

- Excessive rainfall and flash flood risk persist through Tuesday.

- Flood Watch Monday for areas north of the Tennessee River.

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

NEAR TERM

(Today) Issued at 304 AM CDT Mon Jun 8 2026

A nondescript wave of low pressure (initially across the Mid-MO Valley) will shift slowly northeastward over southern IA/northern MO today in conjunction with a faster-moving shortwave trough in the mid-levels. As this occurs, a subtle warm front extending south-southeastward into the TN Valley will continue to advance slowly northeastward early this morning, perhaps initiating redevelopment of showers and thunderstorms in the 9-12Z timeframe from the Lower-OH Valley southeastward into northern portions of MS/AL/GA. Should this occur, the risk for Flash Flooding will increase quickly (particularly in locations impacted by the swath of heavy rain yesterday, where an Areal Flood Warning for excessive runoff and rising river/creek levels remains in effect through 7 AM). Otherwise, a thick layer of very low stratus clouds will gradually expand across the region as temps descend into the u60s-l70s within the very moist airmass locally.

As for the rest of the day, latest CAMs suggest that convection will develop by 16Z across the western portion of the CWFA as the first in a series of subtle low-level confluence axes within the broad warm sector will provide sufficient convergence given the abundance of moisture (PWAT values in the 2.1-2.2" range). Although we will likely experience no direct impacts on deep-layer vertical motions from the shortwave trough to our northwest, a plume of steeper lapse rates along its southern flank will contribute to higher CAPE (1500-2500 J/kg) compared to yesterday, and for this reason we anticipate a significant increase in both lightning and rainfall rates (due to convective enhancement). Thus, the current Flood Watch (in effect from 6 AM - 8 PM) has recently been expanded to include Cullman, Dekalb, Marshall and Morgan counties, as thunderstorms should expand in coverage as they spread slowly east-northeastward across our region.

SHORT TERM

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

The upper trough axis will pivot more southeast Monday night into Tuesday as the ridge builds a bit over the Ozarks. This system generates clusters of convection over the lower OH Valley into middle and western TN Monday night and into the TN Valley and much of AL and GA into Tuesday as the trough shifts southeast. For now, will not extend the Flood Watch past Monday, but this may need to be reassessed depending on Monday's rainfall. The upper ridge will build east into TN/AL and MS by Wednesday, but will not cap off at least diurnally driven convection, mainly in our eastern counties. So low to medium chances remain in the forecast. Temperatures will warm more significantly on Wednesday with highs in the upper 80s to around 90. With dew points in the 70s, heat index values will reach the middle to upper 90s (possibly 100 in far northwest AL).

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

(12Z TAFS) Issued at 646 AM CDT Mon Jun 8 2026

There have been no major changes to previous aviation forecast reasoning, with an overcast MVFR stratus layer and patches of lgt RA in place region-wide. Early development of convective cells is expected btwn 12-16Z as the moist airmass begins to diurnally destabilize ahead of a subtle sfc trough. Current thinking is that coverage of TSRA will be greater today (compared to Sun), with the timeframe of greatest concern for impacts from lightning and torrential downpours coming btwn 16-22Z. There are indications that a slightly drier airmass may infiltrate the region beginning tomorrow evening. Thus, we will indicate no precipitation beyond 22Z, and advertise gradual scattering of the low cloud layer. Prevailing sfc winds will remain from the SSE at 5-10 kts.

HUN WATCHES/WARNINGS/ADVISORIES

AL...Flood Watch through this evening for ALZ001-005>010-016.

TN...Flood Watch through this evening for TNZ076-096-097.