textproduct: Huntsville

KEY MESSAGES

Updated at 1127 PM CDT Thu Oct 1 2026

- Chances for showers and thunderstorms will increase from 20-50% today and tonight to 40-60% by Saturday afternoon. Lightning and brief heavy rainfall will be the main impacts from the storms.

- A fairly widespread coverage of rain (and some embedded thunderstorms) is expected from early Sunday morning through much of the day. The risk for flash and areal flooding will be greatest during this period.

- A cold front will usher a drier airmass into the region early Monday morning, which will remain in place for the rest of the week.

NEAR TERM

(Today) Issued at 353 AM CDT Fri Oct 2 2026

Not much change to the near term forecast as current obs show calm winds across the TN Valley as low/mid level stratus very slowly expands east over AR and MS. Current temps range from the mid 60s to lower 70s making it a warm night compared to recent overnight periods. Expect to see a continued eastward expansion of the mid to low level stratus deck with low to medium (20-50%) chance PoPs entering the forecast around and after noon. The greatest chances for rain and storms today will be over NW AL. Abnormally hot temperatures will lead to minor to moderate HeatRisk levels across the TN Valley this afternoon with highs in the lower 90s and heat indices in the mid 90s nearing 100 degrees in urban locations.

Previous Discussion: In the mid/upper-levels, S-SW flow aloft of 15-25 knots will gradually back to W-SW over the course of the near term period as our region will remain situated between a high centered off the southeastern Atlantic Coast and an amplifying northern stream wave moving eastward across southern OT/QC. At the surface, light- moderate S-SE flow will continue overnight, as a ridge of high pressure shifts eastward off the coast of NC. Although this will not have a significant impact on boundary layer dewpoints, a modest low-level jet will contribute to an increase in low stratus clouds prior to sunrise, which (along with slightly elevated winds) should keep overnight lows in the 65-70F range. Well to the northwest of our region, a cold front extends from central QC southwestward through Lower MI, central IL/MO and to a decaying area of low pressure across northwest TX. As surface pressures gradually rise within an anticyclone across the northern Plains, the front will continue to drift southeastward overnight, but with most of the related precipitation expected to be anafrontal in nature, conditions across our CWFA will remain dry through 12Z.

The cold front will continue to advance slowly southeastward tomorrow as the center of a Canadian surface high migrates further eastward into the Upper MS Valley. Although it appears as if the leading edge of the cooler/drier continental airmass will eventually stall along an axis from northern AR east-northeastward into the central Appalachians, a prefrontal surface trough/wind shift axis well ahead of the thermal/moisture gradient may initiate development of a few showers and thunderstorms tomorrow afternoon (particularly across northwest AL and southern Middle TN, where current POPs are in the 30-40% range). However, additional convection may also evolve in the higher terrain of northeast AL. Instability may initially be limited by morning stratus, but as clouds bases lift during the afternoon, temperatures warming into the u80s-l90s will support CAPE in the 500-1000 J/kg range within an environment of weak shear. Thus, lighting will be the primary concern with thunderstorm activity tomorrow.

SHORT TERM

(Friday night through Sunday night) Issued at 1127 PM CDT Thu Oct 1 2026

Latest short range model guidance suggests that a subtropical ridge will gradually retrograde from the southwestern North Atlantic into the southern Gulf over the course of the short term period. This evolution will maintain weakly confluent flow aloft across our region (between the high to our southeast and a pair of northern stream troughs traveling along the U.S.-Canadian border). Although this type of pattern would normally not be conducive for either widespread or intense precipitation, a surface trough/wind-shift axis will drift further southeastward into the region on Friday night (before becoming stationary on Saturday), and this feature should provide sufficient lift within the increasingly moist airmass (highlighted by PWAT values in the 1.8-2" range, and potentially in excess of 2") to support development of showers and thunderstorms. The spatial coverage of convective cells will be notably higher during the afternoon on Saturday (compared to Friday night) and to the south/east of the streamline confluence axis. However, with a large amount of uncertainty regarding precisely where the boundary will lie, POPs range from 40%/NW to 60%/SE. Weak shear will continue to support unorganized convective updrafts during this period, but afternoon temps in the m-u 80s may support slightly higher CAPE as dewpoints rise into the u60s-l70s. Regardless, lighting and locally heavy rainfall will be the main storm impacts.

During the period from Saturday night-Sunday, the low-level convergence axis may attempt to lift northwestward in response to an amplifying northern stream trough that will travel east- southeastward into southern OT and the western Great Lakes by 12Z Sunday. As this occurs, frontogenetical forcing will gradually strengthen in the lower troposphere, and this coupled with weak lift along the southern flank of the trough to our north may result in an increase in both the coverage and intensity of rain and embedded thunderstorms beginning early Sunday morning and continuing for much of the day. Although weak shear and instability will continue to limit storm intensity, it is during this timeframe that the risk for flash and areal flooding will be greatest (especially as PWAT values may be in excess of 2"). Current thinking is that rain and thunderstorms will slowly end from NW-to-SE late Sunday afternoon and Sunday evening as a cold front shifts southward into the forecast area, with strengthening N-NE winds in the wake of the front advecting a drier airmass into the northern part of the region by early Monday morning. High temperatures on Sunday will be reduced to the 75-80F range due to widespread clouds and precipitation, with temps by Monday morning falling into the u50s-l60s.

LONG TERM

(Monday through Thursday) Issued at 1127 PM CDT Thu Oct 1 2026

Global models suggest that a reinforcing surface high will shift eastward from the Upper MS Valley into the Mid-Atlantic region on Monday and Tuesday, with moderate N-NE flow veering to the SE as pressures begin to rise to the east of the central/southern Appalachians. Although a temporary increase in clouds (and perhaps a few light showers) may occur at the onset of this regime on Tuesday, a drier airmass will likely return from the east for the last couple of days of the forecast period. Afternoon highs will remain in the u70s-m80s, with overnight lows in the m40s-l50s.

AVIATION

(12Z TAFS) Issued at 658 AM CDT Fri Oct 2 2026

VFR conditions have lingered longer than originally forecast this morning as low to mid stratus expands both to our west and east. It remains low confidence when or if these conditions will make it to our area this morning, but lower cigs are forecast at least by the overnight hours tonight. Low chances for rain and thunder will exist over NW AL today, so included a PROB30 group at MSL to cover this risk. Confidence in thunderstorm coverage closer to the HSV terminal is much lower, so we have left any mention of rain out of the TAF for now. Amendments may be needed if cloud cover trends speed up this morning.

HUN WATCHES/WARNINGS/ADVISORIES

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