textproduct: Huntsville

KEY MESSAGES

Updated at 311 AM CDT Mon Mar 9 2026

- There is a low to medium risk of strong to severe thunderstorms this afternoon and evening across the TN Valley.

- There is a low to medium risk of severe thunderstorms on Wednesday.

- Cooler conditions return Thursday, but temperatures should warm as we go into the weekend.

NEAR TERM

(Today) Issued at 311 AM CDT Mon Mar 9 2026

Fog started to develop yesterday evening and has progressed in coverage and density overnight. With this, a Dense Fog Advisory is in effect until 10am this morning for the entire TN Valley. Please give yourself extra time this morning for your morning commute and extra space between vehicles.

Once the hazard of fog is gone this morning, we turn our attention to later this afternoon and this evening. We will start the day off dry, but a boundary to our south will lift northward as a warm front. This will pull lower 60 dewpoints into the forecast area by this afternoon and help temps reach the mid to upper 70s. A shortwave will spark up convection in OK and the Lower MS Valley this morning, and that feature will bring strong to severe thunderstorms to us by the afternoon hours. High Res models are in fair agreement the line of convection will arrive on our doorstep of NW AL 19-22Z (2-5pm) and exit the CWA around 00-02Z (7-9pm). SPC expanded the outlooks for today, extending the Marginal eastward to include nearly all of the CWA, and the Slight Risk now clips the SW portion of Franklin Co (AL) and southern Cullman Co. They also brought up the 2% tornado risk to reach a line that stretches from Florence, to Decatur, and over to Holly Pond. Damaging winds and marginally severe hail remain our primary threats with forecast soundings showing CAPE reaching 1,000-1,500 J/kg, 0-6km shear 40-50kts, 0-3km shear and mid-level lapse rates 6-7 C/km, just to name a few. Higher parameter values will be found to our southwest. Ensure you stay up to date with the latest forecast and have more than one way to receive warnings throughout the day.

SHORT TERM

(Monday night through Wednesday) Issued at 1129 PM CDT Sun Mar 8 2026

This system should take on a more easterly trajectory as we go into the evening. Shower activity (and intensity) should fade from west to east as we go into the later evening and overnight. Nighttime temperatures should be a bit milder with as warm air advection takes hold, with lows from the upper 50s east to lower 60s elsewhere.

Back to a larger scale view. An upper level cutoff low that was part of a troughing feature over the western CONUS was situated west of the northern Baja. This low should remain west of the Baja on Monday, but will begin heading eastward Monday night into the mid week, and again part of the mean westerly flow trough. The trough as it moves over the low/mid Mississippi River Valley will take on a neutral to a slight negative tilt as it moves across the eastern third of the Lower-48 in the midweek. The low will spawn the development of low pressure across the central Front Range on Tuesday, that will head towards the Great Lakes on Wednesday. Another low is expected to form move over TX/OK Tue/Wed and head to the east.

Residual moisture and resultant instability from modest to strong daytime heating will keep low/medium shower and thunderstorm chances in the forecast on Tuesday. As the above noted system nears, higher chances of showers and storms are expected Wednesday, especially in the afternoon and onwards. A warmer trend is expected Tuesday, with highs rising into the mid 70s to around 80, as a steady flow from high pressure to our east resumes. This warm spell will continue Tue night with unseasonably mild conditions in the low/mid 60s. Wednesday will feature one last warm day for a couple of days, with highs again in the upper 70s to around 80.

LONG TERM

(Wednesday night through Sunday) Issued at 1129 PM CDT Sun Mar 8 2026

Models continue to show the strong upper low proceeding east along the Gulf coast states after being pulled east by an amplified longwave trough axis extending northeast into southeastern Canada on late Wednesday afternoon into Wednesday night. A weak surface low is shown in most guidance a bit east of this upper low. Very deep and strong forcing is show with this system. The strength of this forcing is fueled by strong coupled upper level jets. PWATS climb to over 1 inch by the early evening hours. Not an overly saturated sounding, but given strong shear and forcing, heavy rainfall and thunderstorm activity is expected if surface based instability is realized.

Models have been fairly consistent that at least some SBCAPE will be in place during the late afternoon hours. How much has been more variable in ensemble guidance. Expect high rain and thunderstorm chances (70 to 90%) to develop during the evening hours. Either way, there will likely be at least a few hundred to around 500 J/KG in place during the afternoon hours before decreasing but remaining just enough instability to be surface based into the late evening hours potentially. With shear 0-6 km shear values between 40 and 70 knots, organized strong to severe storms look very possible, unless instability doesn't materialize. Damaging winds looks like the biggest threat. Helicity doesn't look strong until after the front pushes into the area behind the convection. The most widespread and heaviest storms/rainfall looks to be more over central and southern Alabama given the track of the surface low in most models and overall ensemble guidance. Still could get between 1 and 1.5 inches south of the Tennessee River given the current track. If the surface low trends further north in future guidance, a more widespread severe and heavy rainfall threat could materialize.

Rainfall and thunderstorm activity will likely last through the overnight hours into early Thursday morning before exiting into Georgia and the Carolinas by noon on Thursday. Colder air will quickly move into the area behind the front as temperature drop into the upper 30s to lower 40s. It will be much colder on Thursday with highs only reaching the 55 to 60 degree range despite abundant sunshine (20 to 25 degree difference from the day before). So, it should be a bit of a shock to the system after the recent warmth. A warmup will build back into the area as weak northwest flow becomes more zonal over the CONUS. It will still be cool though Friday night with lows dropping into the 40 to 45 degree range mainly.

Highs with sunny skies on Saturday should climb back into the lower to mid 70s. Continue southerly to southwesterly low level flow will help bring more moisture back into the area. This should help lows warm into the upper 40s to around 55 degrees. A warming trend will continue through next weekend, with no rainfall expected.

AVIATION

(06Z TAFS) Issued at 1241 AM CDT Mon Mar 9 2026

Fog formed over the region late Sun evening, enough for a local Dense Fog Advisory until 15Z Mon AM. Fog over the area should dissipate after daybreak, and as low/mid clouds move across the area from west to east in the later morning and afternoon. A storm system now moving across east TX will approach the area in the mid and late afternoon, producing scattered to numerous showers and thunderstorms. Some of the storms could become severe, especially over NW AL in the late afternoon and early evening. Convection should move in a west to east manner across the TN Valley tonight, with the general strength of storms slowly waning as we go into the later portion of the TAF.

HUN WATCHES/WARNINGS/ADVISORIES

AL...Dense Fog Advisory until 10 AM CDT this morning for ALZ001>010- 016.

TN...Dense Fog Advisory until 10 AM CDT this morning for TNZ076-096- 097.