textproduct: Huntsville

KEY MESSAGES

Updated at 1039 PM CDT Wed Apr 15 2026

- There is a low-medium (20-50%) chance for showers and thunderstorms Thursday (mainly afternoon and evening). A few storms could produce strong winds and small hail.

- There is a high (60-80%) chance for showers and thunderstorms late Saturday afternoon and evening. A few storms could produce strong winds and small hail.

- A cool/dry airmass will overspread the region Sunday and Monday, followed by a gradual warming trend through Wednesday.

NEAR TERM

(This Evening through Thursday) Issued at 1039 PM CDT Wed Apr 15 2026

Over the course of the near term period, a weakening mid-level shortwave trough will advance east-northeastward from the MO Valley into the eastern Great Lakes within the flow around a dampening subtropical ridge centered across the eastern Gulf. However, along the southwestern flank of the trough, subtle amplification of a secondary 500-mb wave is predicted to occur as it lifts east- northeastward from the southern High Plains into the Mid-South region. In the low-levels, a weakening area of low pressure (related to the northern trough) should reach Lake MI by 12Z Thursday before tracking further east-northeastward into southern QC/northern New England by 0Z Friday.

Clusters of showers and thunderstorms in the vicinity of a surface trough extending south-southwestward from the low will remain to our west through sunrise, although modest elevated warm/moist advection associated with a 20-25 knot southwesterly low-level jet will contribute to an increase in stratocumulus clouds and perhaps a few sprinkles of rain (mainly across the western portion of the CWFA) early Thursday morning. Otherwise, a light SSW wind at the surface will lead to another mild night, featuring lows ranging from the m-u 50s (northeast AL) to the l-m 60s (elsewhere).

Partly-mostly cloudy skies and perhaps a few light showers will continue across the region late tomorrow morning, as an outflow boundary spreads eastward in advance of a diminishing area of rain and some embedded thunderstorms to our west. However, forecast soundings indicate that skies will partially clear beginning early tomorrow afternoon, with redevelopment of showers and thunderstorms expected to occur in the vicinity of the increasingly diffuse surface trough (or perhaps a mesoscale boundary) extending from eastern KY southwestward into northern MS. Storm coverage will likely be limited by weak low-level convergence, warranting a gradient in POPs from 10-20%/SE to 40-50%/NW. However, with CAPE reaching 500-750 J/kg as temps rise into the l-m 80s and WSW flow aloft of 45-50 knots providing sufficient deep-layer shear for storm organization, a few cells producing small hail and strong wind gusts up to 40-50 MPH may occur.

SHORT TERM

(Thursday night through Saturday night) Issued at 1039 PM CDT Wed Apr 15 2026

During the afternoon hours tomorrow, convection-allowing models suggest that scattered thunderstorms will develop in the vicinity of a trailing outflow boundary (extending from western AR into southern MO). As large scale ascent strengthens with the approach of an amplifying mid-level wave, this activity may tend to evolve into a small but somewhat organized cluster of storms as it spreads southeastward late tomorrow afternoon/early tomorrow evening, before gradually dissipating later tomorrow evening as it becomes displaced from the initiating trough. Although the system should be weakening as it tracks across our CWFA, a second round of rain and some thunderstorms may occur early tomorrow evening, accompanied by a risk for locally strong wind gusts (especially across northwest AL). Otherwise, patchy fog will be possible in locations that are fortunate enough to receive measurable rainfall as temps drop into the u50s-l60s.

South-southwesterly flow will resume on Friday as a surface low develops north-northeastward (from eastern NE into western Lake Superior) in response to an intensifying trough tracking eastward across southern Canada and the northern Great Plains. With a developing subsidence inversion in the mid-levels expected to result in mostly sunny skies and dry conditions on Friday, afternoon temps will return to the m-u 80s, which may fall just shy of record highs for the day. Overnight lows will drop into the l-m 60s Saturday morning.

Latest short range model guidance still suggests that rapid intensification of the northern stream trough will support steady deepening of the related surface low as it tracks northeastward across eastern OT and into northern QC by 12Z Sunday. As this occurs, a cold front will spread southeastward, likely reaching northwestern AL late Saturday afternoon and exiting our forecast area by Midnight. After diminishing in coverage during the morning hours on Saturday, thunderstorms are expected to redevelop along the southern portion of the cold front Saturday afternoon as the boundary layer destabilizes and a lingering layer of stable air aloft begins to erode with the approach of the mid-level trough. With mid-level WSW flow predicted to increase into the 50-60 knot range Saturday evening, deep-layer shear will be sufficient to support organized storm clusters, capable of producing small hail and strong wind gusts. However, this will likely be more of a concern across northwest AL where instability will be maximized around the time of frontal passage. In the wake of the front, a 2-4 hour window of light rain can be expected, as winds veer to the north and begin to advect a cooler continental airmass into the region.

LONG TERM

(Sunday through Wednesday) Issued at 1039 PM CDT Wed Apr 15 2026

An upper level trough will be swinging from the Ohio and Tennessee valleys over the eastern seaboard through Monday. Ridging tries to build in the wake of this through midweek, but a few shortwave ripples are shown to dive into the region from the mid Mississippi River Valley during this time. At the surface, a cold front will have passed to our southeast by Sunday morning, with high pressure from western Canada and the northwest CONUS pushing into the Southeastern states. This feature will largely maintain its hold on the eastern CONUS until it is shunted eastward through midweek by a system sweeping over Canada.

For sensible weather for the local area, there may be some lingering showers early Sunday morning from the system that is slated to move through on Saturday (discussed above), but much of the long term period looks to be dry. Although, we will need to keep an eye on Wednesday, as some guidance hints at the potential (albeit low probability) for the aformentioned upper shortwaves to bring some rain to the Tennessee Valley. Confidence is low at this point due to model discrepancies, but stay tuned!

Don't pack those jackets away for the season just yet, since it will be fairly cool to start the week. Cold air advection from the high pressure moving in from the northwest CONUS and western Canada will result in highs topping out in the 60s Sunday afternoon and forecast lows in the upper 30s to lower 40s Sunday night! Monday will be pleasant with highs in the lower 70s with lows in the 40s that night. Fortunately or unfortunately (depending on if you like or dislike cooler weather), temperatures will then begin to moderate once again through midweek. Expect highs to warm into the upper 70s to around 80 degrees by Wednesday.

AVIATION

(06Z TAFS) Issued at 1234 AM CDT Thu Apr 16 2026

Winds will become gusty late this morning and afternoon out SW/WSW between 10-15 kts before weakening after sunset. A weak front will approach the area from the northwest, bringing some -SHRA during the late morning through mid afternoon and have added a PROB30 highlight this. Overall, VFR conditions will be the predominant flight category at each terminal through the period.

HUN WATCHES/WARNINGS/ADVISORIES

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