textproduct: Huntsville

KEY MESSAGES

Updated at 328 AM CDT Thu Jun 18 2026

- Medium to high chances for rain and thunderstorms today as the remnants of Arthur track along the Gulf Coast states. There is a Slight Risk (level 2 of 4) for excessive rainfall/localized flooding and a Marginal Risk (level 1 of 5) for gusty to damaging thunderstorm winds.

- After a brief period of dry weather late Friday into Saturday morning, additional rounds of rain and thunderstorms are forecast into the long term period with high rain chances Sunday and Monday.

NEAR TERM

(Today) Issued at 328 AM CDT Thu Jun 18 2026

An early morning look at satellite and current observations show temps about 10 degrees above normal, contributing to the Moderate HeatRisk across portions of the area. Satellite shows low stratus has developed a little earlier than anticipated 24 hours ago but has kept fog formation at bay. As moisture continues to be pushed north as the remnants of Arthur track along the LA/MS coast and eventually into central MS/AL, rain chances will increase just after sunrise from south to north as outer bands from this disturbance track into the TN Valley. It is worth mentioning that while rainfall totals have decreased significantly over the past 24-48 hours, PWAT values at or just above 2" (climatologically in the 99th percentile) will allow for heavy rainfall rates and can lead to ponding on area roadways or localized flooding fairly quickly, especially for locations that see repeated showers/storms. Rainfall amounts are forecast to range from 0.25-0.5" north of the TN River to 0.5-1" along and south of the TN River.

Although the threat remains low, any strong updrafts that do form and track into the area will carry the risk for gusty to damaging winds. While lapse rates aren't overly impressive, LCLs will be low and HREF ensemble guidance shows SBCAPE values will range from 1500-2000 J/kg this morning ahead of the approaching sfc low. If any storms are able to form out far ahead early this morning they would need to be monitored closely for both heavy rain and damaging winds. Wind shear profiles do not look particularly favorable this far north until later this afternoon when the sfc low tracks near NE AL. By this time, instability parameters are forecast to be lower and should limit a greater severe risk as the system continues to decay. We feel confident that the bigger concern for damaging winds and tornadoes will be south of our area today given the current track and more favorable shear, but any deviations north would increase the risk for both damaging winds and flooding.

Rain should begin to clear NW AL in the early afternoon and gradually clear to the east this evening. Expect highs in the low to mid 80s with cloudy skies and gusty southerly winds up to 25mph at times.

SHORT TERM

(Thursday night through Saturday night Issued at 1006 PM CDT Wed Jun 17 2026

The forecast isn't done after the remnants of Arthur gets out of here, as there is a cold front on our doorstep.

Luckily, the cold front has been trending on the later side, letting the remnants of Arthur slip on by before it arrives Friday morning. Consensus is that it will start to push into the TN Valley Friday morning around sunrise, and push south of us after lunch. It is uncertain on how much convection it will develop. There will be decent bulk shear available, but instability really decreases and moisture content decreases (dewpoints, PWATs) as well. Daytime highs will reach the low to mid 80s, and lows will be several degrees cooler in the low to mid 60s.

We'll really see some drier air filter in on Saturday, allowing for a decrease in cloud cover. However, we can't fully escape the rain though as a disturbance sliding through will provide us with low chances (20% NE AL/S Mid TN - 30% elsewhere) of showers and thunderstorms through the day and into Saturday night. Highs may be in the mid to upper 80s but the dewpoints will be lower than previous days.

LONG TERM

(Sunday through Wednesday) Issued at 1006 PM CDT Wed Jun 17 2026

Zonal flow will largely persist through much of the long term period, with several ripples of shortwaves moving along the flow during this time. However, the pattern looks to change a bit by midweek, with northwest flow taking hold. At the surface, a remnant boundary will either dissipate or move north of the region on Sunday. Another cold front is then shown to approach the Southeast on Monday, with FROPA through north Alabama and southern middle Tennessee sometime between Monday night and Tuesday. High pressure then builds down into the Tennessee Valley quickly behind the front for midweek.

Overall, expect daily chances of showers and storms, but with higher chances Sunday and Monday (40-80%) and lower chances Tuesday and Wednesday (20-40%). While thunderstorm development is supported due to sufficient instability and bulk shear, guidance suggests midlevel lapse rates mainly between 5-6.5 degC/km. Therefore, confidence is low in any strong to severe storm potential at this point. However, with PWATs between 1.7-2.1 inches Sunday and Monday, these storms will be efficient rainfall producers and bring the threat of heavy rainfall and at least minor flooding (especially with saturated antecedent conditions). Moisture gradually decreases from Tuesday into Wednesday, with a more summertime-like pattern then setting up (diurnal showers/storms).

As for temperatures, highs will generally remain in the mid to upper 80s Sunday through Wednesday. But, lows will gradually decrease from the lower 70s Sunday night to the mid to upper 60s by Tuesday night thanks to FROPA and decreasing moisture.

AVIATION

(12Z TAFS) Issued at 635 AM CDT Thu Jun 18 2026

MVFR to IFR stratus continues to overspread the region early this morning as an approaching tropical system has resulted in increasing moisture and cloud cover across much of the Southeast. Rain chances will increase after 15z this morning as the system nears and will bring widespread showers and storms to the area through this afternoon. Reductions to MVFR or IFR conditions are likely during heavier showers and low to medium chances for rain will continue through the end of the TAF period. S to SW winds will gust up to 20kts at times, especially during the daylight hours. Amendments may be needed if rain begins earlier than currently expected.

HUN WATCHES/WARNINGS/ADVISORIES

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