Clusters of strong to severe thunderstorms developed during the early to mid afternoon hours. One of the storms resulted in wind damage.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS HUN wrote it up.
Clusters of strong to severe thunderstorms developed during the early to mid afternoon hours. One of the storms resulted in wind damage. Excessive rain in northwest Alabama led to a few reports of flash flooding. In addition, before the thunderstorms developed, a funnel cloud descended from a building shower near the southern portion of Lake Guntersville in Marshall County. Multiple photos of the funnel were shared via social media.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Huntsville, AL wrote its last area forecast discussion before the first event at Aug 30, 9:29 AM CST, 2 hours 1 minute earlier.
Area Forecast Discussion National Weather Service Huntsville AL 1029 AM CDT Sun Aug 30 2020 .NEAR TERM...(Rest of Today) Issued at 1029 AM CDT Sun Aug 30 2020 A frontal boundary that was well north of this region yesterday has moved further southward, now extending from coastal North Carolina, to far south/central Kentucky, and Oklahoma. Given a weak low along the TN/KY border, the front may sag a bit further south across western TN later today and this evening. All in all, this boundary should remain north of the greater Huntsville Forecast Area. The front nearby, along with moisture convergence has resulted in variable clouds across the Tennessee Valley. Parts of the area were experiencing mostly sunny skies, with mostly cloudy to cloudy skies elsewhere. This of course was changing, as daytime-heating-produced cumulus form in the more sunny areas, and clouds associated with outflow boundary interact. The radar indicated a lone shower near Moores Mill and Gurley headed eastbound. More organized convection was moving eastward across NW Mississippi. More clouds than sun, and higher rain chances will keep high temperatures a tad cooler, in the upper 80s to around 90. The activity over MS, and other development hinted at by various shorter term models, will bring better rain chances to the area late this morning and in the afternoon. Given the approaching showers from the west, have stayed with higher PoPs ~60 percent, with only 20 percent over NE AL. Scattered to numerous rain chances should overspread the area from west to east during the course of the afternoon. Given deeper moisture with precipitable water amounts in the 2 inch range, CAPE values rising above 2000 J/kg, and an inverted V sounding, is suggestive that some of the storms will be capable of producing strong to marginally severe outflow winds. The area is in a risk for marginally severe thunderstorms. Torrential downpours are also possible. Given the proximity of the front, our northern areas would be more susceptible to flooding from excessive rainfall, thus a slight risk of flash flooding exists for those areas. .SHORT TERM...(Tonight through Tuesday) Issued at 144 AM CDT Sun Aug 30 2020 The short range models suggest continued development of convective clusters across much of the mid South and Tennessee Valley through tonight. This will be supported by southwesterly 8h flow increasing again tonight along with multiple weak shortwaves traversing the westerly flow aloft. This pattern will persist through Monday as well, so will have to watch the potential for local problem areas for flooding. Will keep PoPs rather high during this period. There may be a reduction in activity Monday night as weak ridging in mid to upper levels occurs between shortwaves. However, another stronger wave eject from the southern Plains into the eastern corn belt through the lower OH/TN valleys Tuesday. This should generate another band of thunderstorms sometime on Tuesday, although these should be more progressively moving northeast by later in the afternoon or evening. .LONG TERM...(Tuesday night through Saturday) Issued at 144 AM CDT Sun Aug 30 2020 A positively tilted shortwave trough in mid levels will dig into the Four Corners as strong ridging builds in the Desert Southwest. Over the Southeast, the Bermuda High will build into the region and cause the mid level trough to stall over the Southern Plains through the mid-week period. As a result, subsidence will limit convective coverage and allow only isolated to scattered diurnal showers and thunderstorms on Wednesday and Thursday. High temperatures will reach the upper 80s to near 90 with muggy nights only dropping to the low 70s. A negatively-tilted shortwave trough at 500 mb and associated surface low pressure system will swing through Ontario and help push both the stalled trough and surface boundary eastward. Models diverge on whether or not the Bermuda High recedes back over the Atlantic. The trend has been for lower 500 mb heights, therefore allowing the trough axis to swing through the TN Valley. A cold front trailing from the attendant surface low is currently forecast to progress through the region and stall over the northern Gulf Coast. Should the front make it through the TN Valley, expect higher shower and thunderstorm coverage on Friday and Friday night due to greater synoptic forcing from the surface boundary. Although it is shallow, we should see some relief with dew points dropping into the mid 60s Friday night and Saturday. High temperatures for the weekend will be in the mid 80s with pleasant overnight lows in the mid 60s. && .AVIATION...(For the 12Z TAFS through 12Z Monday morning) Issued at 633 AM CDT Sun Aug 30 2020 Clusters of SHRA and TSRA will occur over southern TN and far north AL through this morning. Most of this activity will remain north of KMSL and KHSV this morning, so have gone with VCSH at both locations. TSRA are more likely by 17-19Z and have gone with VCTS and a corresponding TEMPO group from 17-21Z at KMSL and 19-22Z at KHSV. The chance of TSRA continues tonight, but confidence in timing at the terminals remains low, so have left out on this issuance. VFR conditions should prevail outside of TSRA, but patchy FG/BR will be possible again late tonight and early Monday morning. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && NEAR TERM...RSB SHORT TERM...17 LONG TERM...25 AVIATION...17 For more information please visit our website at weather.gov/huntsville.
Hazardous Weather Outlook National Weather Service Huntsville AL 1213 PM CDT Sun Aug 30 2020 ALZ001>010-016-TNZ076-096-097-311100- Lauderdale-Colbert-Franklin AL-Lawrence-Limestone-Madison-Morgan- Marshall-Jackson-DeKalb-Cullman-Moore-Lincoln-Franklin TN- 1213 PM CDT Sun Aug 30 2020 This Hazardous Weather Outlook is for north central Alabama, northeast Alabama, northwest Alabama and southern middle Tennessee. .DAY ONE...This afternoon and tonight. Thunderstorms will become numerous across the area this afternoon and evening, with gusty winds and heavy rainfall possible. Localized flooding could result from slow moving storms or storms that repeatedly move across the same area. .DAYS TWO THROUGH SEVEN...Monday through Saturday. Thunderstorms will be possible on Monday and Tuesday, with gusty winds and heavy rainfall possible. Lesser coverage of storms is expected Wednesday through Saturday, with isolated thunderstorms possible each day during this time. .SPOTTER INFORMATION STATEMENT... Activation of storm spotters and emergency management personnel is not anticipated at this time. 12
The Northeast Alabama radar (KHTX), 77 km away, was scanning. The volume nearest the first event began at 17:31 UTC.
6 flash flood, 1 funnel cloud, 1 thunderstorm wind, 1 heavy rain. Local standard time, as filed.
Photos and video of a funnel cloud were received around 11:30 CST in the general vicinity of Pleasant Grove, near the southern end of Lake Guntersville. It is not clear if the funnel cloud touched down (i.e. land spout or waterspout). Location was estimated on multiple photo descriptions.
A tree was knocked down at 3300 North Pike. Time estimated by radar.
Flash flooding reported on Cloverdale Road. Water was up to exhaust on cars in the parking lot. This replaces a previous report on Cloverdale Road.
Flooding was reported at the intersection of Sockwell Road and Highway 20.
Flooding was reported at the intersection of Old Highway 20 and Cornelius Landing.
Flash flooding reported at the intersection of Old Highway 20 and Barbara Street.
A few roads were closed due to flooding between Chisolm Road and Helton Drive in Florence.
Flooding was reported in Moulton.
Rainfall amount of 2.79 inches of rain measured in one hour. Storm total amount likely higher, but power outage occurred shortly thereafter.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alabama in 2020Every state in 2020This day in weather historyWarnings in Alabama, August 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 906954, 918067, 919511, 919513, 919516, 919517, 919520, 919522, 919523.