textproduct: Huntsville

KEY MESSAGES

Updated at 303 AM CDT Sun Jul 12 2026

- A slightly lower coverage of showers and thunderstorms is expected on Sunday/Sunday evening, but stronger cells will be capable of producing brief strong winds and frequent lightning.

- The coverage of showers and thunderstorms will increase once again on Monday-Tuesday, with lightning and heavy rainfall/flash flooding the main impacts.

- A progressively lower coverage of afternoon thunderstorms is expected from Wednesday-Saturday, with dangerous heat becoming an increasing concern by Friday/Saturday.

NEAR TERM

(Today) Issued at 303 AM CDT Sun Jul 12 2026

Some lingering showers from convection yesterday remain across portions of the Tennessee Valley. These continue to wane and should dissipate as we head towards sunrise. During the day, a sfc low will push eastward across Tennessee. Not as hot today with highs in the mid to upper 80s as cloud cover will limit solar heating. However, it is still quite humid with dewpoints in the lower 70s. The sfc low will help develop showers and thunderstorms by this afternoon, once the atmosphere destabilizes. Latest CAMs show around 1000-1500 J/kg with vertical soundings having a more skinny CAPE appearance with poor lapse rates. Given the lack of wind shear, storms will have a hard time becoming organized, but a strong to severe storm cannot fully be ruled out especially east of I-65. As a result, the SPC has placed out eastern half of the CWA in a level 1 of 5 (marginal) risk. The main threat will be gusty to damaging winds. Pwats are once again between 1.8-2 inches meaning any strong storm can produce locally heavy rainfall that could lead to flash flooding.

SHORT TERM

(Sunday night through Tuesday night) Issued at 1009 PM CDT Sat Jul 11 2026

Latest short range model guidance suggests that a mid-level shortwave trough (and its related surface low) will remain nearly stationary across the TN Valley on Sunday night and Monday, before gradually decaying from Monday night-Tuesday night as both begin to travel westward in the flow around a strengthening 500-mb high across the northern Plains. Convection (that will likely be ongoing across portions of the region late Sunday afternoon) should become focused across our southeastern counties Sunday evening (ahead of a subtle low-level confluence axis attached to the low) before largely dissipating by late evening. However, low stratus clouds and perhaps a few light showers (in the immediate vicinity of the low) may impact portions of the CWFA through early Monday morning.

Thunderstorms should redevelop rather quickly after sunrise Monday morning in the general vicinity of the same low-level confluence axis (across our southeastern zones) before developing further northwestward across the remainder of the forecast area during the afternoon. Showers and some thunderstorms may continue for much of Monday night (especially in southeastern portions of the forecast area, where a residual low-level confluence axis will lie), with a similar scenario expected to unfold region-wide on Tuesday. However, by Tuesday night, the decaying surface low should be sufficiently far to our west to reduce low-level convergence and the risk for nocturnal convection. Fortunately, the combination of weakening lapse rates aloft and abundant low cloud cover will result in a progressively lower risk for strong- severe downburst winds each day. However, as southeasterly deep- layer flow becomes increasingly established, high PWAT values (2+") will yield a persistent risk for locally heavy rainfall and flash flooding. Daily high temperatures will remain in the l-m 80s, with overnight lows in the u60s-l70s.

LONG TERM

(Wednesday through Saturday) Issued at 1009 PM CDT Sat Jul 11 2026

Throughout the extended forecast period, global models indicate that a strong mid-level high (initially positioned across the northern Plains) will develop southeastward, becoming centered across western portions of the Lower MS Valley by Saturday. Although the precise location of the high and extent of the ridge are unclear at this time, subsidence and drying aloft will likely contribute to a lower (but non-zero) spatial coverage of thunderstorms each day from Wednesday-Saturday. That said, conditions will become increasingly favorable for strong-severe downburst winds with any thunderstorm activity (particularly by Friday/Saturday). Unfortunately, the synoptic pattern suggests that dangerous afternoon heat will likely become an increasing concern as we head into late next week and early next weekend, as high temperatures will warm back into the lower 90s. This, along with dewpoints in the mid 70s, will send heat indices back over 100F for much of the region.

AVIATION

(06Z TAFS) Issued at 1247 AM CDT Sun Jul 12 2026

There have been no significant changes to previous aviation forecast reasoning, and with only a few pockets of lingering lgt RA noted in radar data we will not mention this in the TAFs attm. As a result, VFR conds will continue early this morning, with an overcast As layer in place and potential development of lower stratus and perhaps some lgt BR/FG in the 10-14Z timeframe. Diurnal warming of the moist boundary layer will contribute to redevelopment of sct-bkn CuCon by 16Z, with additional clusters of TSRA expected to evolve by late morning across Middle TN, before spreading southeastward into northern AL btwn 18-0Z. In the wake of this activity, lgt SW winds will veer to NW and a low stratus deck will redevelop by 3Z.

HUN WATCHES/WARNINGS/ADVISORIES

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