textproduct: Huntsville

KEY MESSAGES

Updated at 1135 AM CDT Sat May 23 2026

- A wet weather pattern will continue for the next seven days with an additional 2.5-4 inches of rain expected. Thus, there is at least a low risk of flooding into next week.

NEAR TERM

(Rest of Today and Tonight) Issued at 1135 AM CDT Sat May 23 2026

Over the course of the near term period, a decaying surface low (related to a low-amplitude 500-mb shortwave trough) will shift northeastward across northwestern OH today before turning northward over Lake Superior tonight. A slow-moving surface trough/wind shift axis extending southwestward from the low through Middle TN and into northern MS will likely provide the low-level forcing for initiation of diurnally-enhanced showers and thunderstorms later today, but it appears as if the overall coverage of convection will be reduced region-wide (and perhaps limited to just northwest AL) by broad scale subsidence in the wake of the departing mid-level trough and drying profiles aloft. However, the local storm environment will be characterized by higher values of both MLCAPE (1500-2000 J/kg) and DCAPE (600-800 J/kg) than we have seen in recent days, partially as a result of greater insolation (afternoon temps in the u70s-l80s) and steepening lapse rates in the mid-levels. Thus, the risk for locally damaging downburst winds (up to 50-60 MPH) will exist with stronger cells within the generally weak deep-layer shear regime (highlighted by 20-30 knot SW flow aloft).

Beginning late this afternoon and continuing throughout the evening, attention will turn to the southwest, as several CAMs are now suggesting that a large MCS (currently in progress across LA) may spread northeastward and into our CWFA between 0-6Z. Should this occur, the system will likely be on a gradual weakening trend concurrent with the onset of the nocturnal cooling cycle, but may still bring brief gusty winds, lightning and heavy rainfall to a majority of the region. Pockets of light rain appear likely to continue early Sunday morning as low stratus clouds become reestablished, with overnight lows ranging from the l60s in northeast AL to the m-u 60s elsewhere.

SHORT TERM

(Sunday through Monday night) Issued at 1135 AM CDT Sat May 23 2026

Short range model data suggests that a weak southern stream vort max (predicted to cross the Rio Grande Valley later today) will gradually evolve into a cutoff low across eastern TX through Monday night, as an amplifying trough to its north lifts out to the northeast. In response to this, a broad region of slowly falling surface pressures will remain centered across the western Gulf and adjacent portions of south TX/northeast Mexico, with an effective warm front spreading gradually northward across the Gulf Coast states and into the OH Valley. As deep-layer flow across our region backs to SSW, rich/tropical moisture will return to the region, with PWAT values expected to rise back into the 1.7-1.9" range tomorrow. Although weaker and nearly moist adiabatic lapse rates in this regime will reduce CAPE, diruanlly-enhanced convection is still anticipated to develop during the afternoon hours, particularly in the vicinity of any mesoscale boundaries left behind by overnight showers/storms.

The spatial coverage of showers and thunderstorms (driven largely be deep-layer warm/moist advection) will begin to increase at some point Monday morning and should remain rather widespread for much of the day and into the evening hours before diminishing from S-to-N early Tuesday morning as the effective warm front progresses northward and away from our region. Although southerly flow at the 850-mb level may eventually strengthen to 20-30 knots from late Monday afternoon into the overnight hours, weak instability during this timeframe will significantly reduce the risk for strong-severe thunderstorms. However, given the widespread nature (and extended period) of moderate-locally heavy rainfall, another Flash Flood Watch may need to be considered. Temperatures will fluctuate very little through the short term period, with highs remaining in the u70s-l80s and lows in the 60s.

LONG TERM

(Tuesday through Friday) Issued at 1032 PM CDT Fri May 22 2026

Unsettled weather will continue for the rest of the week. A larger scale upper troughing west and ridging east big picture pattern is expected. A deep southerly lower level flow will also persist. This flow bringing moisture from the Gulf further inland will keep daily chances of showers and thunderstorms in the forecast. The convection should be on a diurnal trend - mainly in the afternoon to early evening hours each day. As such, daily high temperatures should rise into the low/mid 80s, and nighttime lows mainly in the mid 60s. Precipitable water amount in the 1.6 to 1.8 inch range will produce a risk of locally heavy rainfall, with some risks for flooding and at times elevated water levels within area creeks, streams, and rivers.

AVIATION

(12Z TAFS) Issued at 555 AM CDT Sat May 23 2026

A mix of VFR and MVFR conditions were observed over north Alabama at issuance. For the terminals, anticipating low CIGs (mainly MVFR with perhaps instances of IFR) through this morning. Additionally, low to medium chances (30-60%) of showers and storms will prevail through much of the day, with chances decreasing this evening. Expect lower CIGs and VIS in the heavier showers. Otherwise, VFR conditions should largely return this afternoon. Although, conditions are forecast to drop once again late tonight to at least MVFR with rain chances increasing as well. Southerly winds around 5 knots or so will become southwesterly through this morning. Light to calm winds are then anticipated to take hold this evening and continue overnight.

HUN WATCHES/WARNINGS/ADVISORIES

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