Several clusters and bands of strong to severe thunderstorms developed during the afternoon hours of the 27th. These were part of very far outer effects of Tropical Storm Laura tracking into central Arkansas which had weakened from Hurricane status.
Every event with a place to put it. Tap one for its entry below.
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.
Several clusters and bands of strong to severe thunderstorms developed during the afternoon hours of the 27th. These were part of very far outer effects of Tropical Storm Laura tracking into central Arkansas which had weakened from Hurricane status. One of the bands moved rapidly north through northwest Alabama and the Shoals, with a small bow echo noted on radar. There were a few reports of trees and power lines down and roof damage.
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 27, 2:30 PM CST, 18 minutes earlier.
Area Forecast Discussion National Weather Service Huntsville AL 330 PM CDT Thu Aug 27 2020 .NEAR TERM...(Remainder of today and tonight) Issued at 330 PM CDT Thu Aug 27 2020 Latest Doppler radar data currently depicts the development of scattered convection across the local area, to the immediate north of a well-defined band of showers and thunderstorms associated with a low-level streamline confluence axis. Guidance from a majority of the CAMs is in reasonably good agreement in predicting the broader band to shift northward across our region through the remainder of the afternoon, and POPs through 00Z have been adjusted upward to account for this. With strengthening southerly flow aloft and sufficient boundary layer warming now occurring to boost temperatures into the u80s-l90s, MLCAPE in the 1000-2000 J/kg range could support some stronger wind gusts (40-50 MPH) than anticipated in the morning update, but we still expect storms to remain below severe thresholds. As for the remainder of the night, it appears as if convection lingering from this afternoon's activity should largely dissipate after sunset, as the initial outer confluence band extending eastward from Laura lifts further northeastward. However, most guidance suggests that an additional band of showers and thunderstorms may develop across east central MS/west central AL and begin to spread northward early Friday morning, warranting fairly high POPs for the western half of CWFA. Otherwise, given the strength of south- southeasterly flow at the surface and an increase in low stratus clouds around Midnight, we expect another very mild and humid night, with lows in the mid 70s. .SHORT TERM...(Friday through Saturday night) Issued at 330 PM CDT Thu Aug 27 2020 Overall, there has been little change in the short term forecast this afternoon, with the global models continuing to suggest that the remnant vorticity related to Laura will lift northeastward from AR into the Lower-OH Valley tomorrow, before accelerating eastward along the KY-TN border and into the southern Appalachians Friday night. The circulation will gradually open into a wave as it encounters increasingly confluent flow between a 500-mb ridge centered across southern FL and a mid-latitude trough digging southeastward across western Ontario, but the height gradient will remain sufficiently steep to support strong southwesterly gradient flow across the region tomorrow. Sustained winds around 15 MPH can be expected in lower elevations along with gusts in the 20-25 MPH range, and both values will be notably higher in elevated terrain. In fact, conditions will be very close to Wind Advisory criteria in our higher terrain zones for a brief window late Friday night/early Saturday morning, but due to the marginal nature of these conditions and limited areal extent, we will refrain from issuing an NPW at this point. Several bands of convection driven by low-level convergence zones peripheral to the parent circulation of Laura will also pivot east- northeastward across the region during the day tomorrow. This will occur prior to the arrival of the broader region of more widespread rainfall associated with the remnant circulation that will spread east-southeastward through the TN Valley late Friday night/early Saturday morning. Although the southwesterly low-level jet will likely increase to 35-45 knots overnight (well within the range to warrant concern for mesocyclones and tornadoes), the most favorable overlap of deep-layer shear, low-level flow and instability will likely occur during the day on Friday. That said, this still appears to be a low CAPE/high shear case as instability will be limited to 500-1000 J/kg by widespread cloud cover and precipitation. Nonetheless, brief tornadoes will be possible with any low-topped supercells, and the stronger bands of convection will be capable of producing wind gusts in the 40-50 MPH range. Finally, both areal and flash flooding will be a concern given recent heavy rainfall, although average storm total rainfall amounts are still predicted to only reach 1-2 inches. Precipitation should be ending rather quickly from NW-to-SE across the region in the 09-12Z timeframe on Saturday, as deep-layer flow veers to northwest in the wake of the departing trough. Although this may lead to a temporary drying trend on Saturday, the cold front related to a northern stream trough moving across southern Ontario/southern Quebec may drop southward into the region Saturday evening, initiating additional showers and thunderstorms. .LONG TERM...(Sunday through Wednesday) Issued at 330 PM CDT Thu Aug 27 2020 A persistent wet pattern is setting up for the duration of the long term period. Even with Laura far removed from its days of a tropical system, its wake as it continues to phase through its post tropical cyclone life will be felt in the TN Valley. As the remains of Laura merge with a system off the Nova Scotia coastline, an attendant frontal boundary will stretch through the Mid-Atlantic coastline and across the SE US. With this boundary draped over the region, plenty of deep moisture will be primed to support showers and storms each day. The boundary will gradually stall and begin to push more eastward, as like a quasi-warm front by Tuesday, which again, will support showers and storms across the region. Behind the exiting warm front, high pressure will attempt to establish back over the region, as upper level support wanes with energy moving east. Rain will remain in the forecast on Wednesday, but chances will be diminishing. Current QPF forecast keeps total rainfall for the long term period around one inch. However, will need to closely monitor for more persistent, heavy rainfall which would easily cause flood concerns given saturated soils. Temps each today to top out in the mid 80s with lows in the low 70s. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) Issued at 1259 PM CDT Thu Aug 27 2020 VFR conditions currently observed at the HSV/MSL terminals will persist this afternoon, with the development of few Cu expected beneath a bkn-ovc veil of Cs aloft. Sct convection will likely continue to shift northward into the region, driven by a subtle low- lvl convergence axis extending eastward from Hurricane Laura. Based on expected timing of this activity, we have introduced VCSH for both terminals at 21Z, with a TEMPO group for TSRA btwn 22-02Z. Although some showers and thunderstorms could feasibly continue well into the evening and overnight hours, we will refrain from including them in the forecast at this point. However, it does appear as if a stratocu deck will begin to surge northeastward this evening, as the low- level jet strengthens. A period of broken MVFR stratus is expected btwn 08-14Z, at which time LLWS may eventually need to be included due to 30-35 knot flow around 1800-2000 ft AGL. Convection associated with another outer rainband will likely begin to impact the terminals at the end of the period, with PROB30 groups included btwn 14-18Z. Sfc flow will veer from SE to SSW over the course of the TAF period, with sustained speeds around 10 knots and gusts as high as 18 knots during the day. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && NEAR TERM...70/DD SHORT TERM...70/DD LONG TERM...Barron AVIATION...70/DD For more information please visit our website at weather.gov/huntsville.
Hazardous Weather Outlook National Weather Service Huntsville AL 343 AM CDT Thu Aug 27 2020 ALZ001>010-016-TNZ076-096-097-272345- Lauderdale-Colbert-Franklin AL-Lawrence-Limestone-Madison-Morgan- Marshall-Jackson-DeKalb-Cullman-Moore-Lincoln-Franklin TN- 343 AM CDT Thu Aug 27 2020 This Hazardous Weather Outlook is for north Alabama and portions of southern middle Tennessee. .DAY ONE...Today and Tonight... Isolated to scattered thunderstorms will be possible today, mainly during the afternoon and early evening hours. .DAYS TWO THROUGH SEVEN...Friday through Wednesday... Thunderstorm coverage will increase Friday into Saturday, as the remnants of Hurricane Laura move eastward across the Mid South and lower Ohio Valley areas. A few storms may be capable of producing locally heavy rainfall and strong gusty winds. A few tornadoes may also be possible late Friday. Scattered storms will remain in the forecast Sunday and Monday, as a weak frontal boundary settles into the region from the north. .SPOTTER INFORMATION STATEMENT... Formal activation of storm spotters and emergency management personnel is not anticipated at this time. However, timely reports of flooding will be greatly appreciated. Please relay any information about observed severe weather to the NWS while following all local, state, and CDC guidelines.
Special Weather Statement
National Weather Service Huntsville AL
316 PM CDT Thu Aug 27 2020
ALZ003-272100-
Franklin AL-
316 PM CDT Thu Aug 27 2020
...SIGNIFICANT WEATHER ADVISORY FOR WESTERN FRANKLIN COUNTY UNTIL 400
PM CDT...
At 315 PM CDT, Doppler radar was tracking a strong thunderstorm 9
miles north of Weston, moving north at 30 mph.
Winds in excess of 45 mph will be possible with this storm.
Locations impacted include...
Red Bay, Vina, Atwood, Dempsey, Little Bear Creek Reservoir,
Halltown, Pleasant Site and Cedar Creek Reservoir.
LAT...LON 3434 8817 3453 8815 3456 8793 3431 8794
3432 8817 3434 8818
TIME...MOT...LOC 2015Z 172DEG 26KT 3429 8803
KTWSpecial Weather Statement National Weather Service Huntsville AL 330 PM CDT Thu Aug 27 2020 ALZ004-272100- Lawrence AL- 330 PM CDT Thu Aug 27 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN LAWRENCE COUNTY UNTIL 400 PM CDT... At 330 PM CDT, Doppler radar was tracking a strong thunderstorm over Brushy Lake, moving north at 15 mph. Locations impacted include... Moulton, Speake, Bankhead National Forest and Wren. PRECAUTIONARY/PREPAREDNESS ACTIONS... Very heavy rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike several miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3430 8735 3452 8740 3453 8711 3430 8718 TIME...MOT...LOC 2030Z 174DEG 13KT 3432 8725 KTW
Special Weather Statement National Weather Service Huntsville AL 336 PM CDT Thu Aug 27 2020 ALZ002>004-272100- Lawrence AL-Franklin AL-Colbert AL- 336 PM CDT Thu Aug 27 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN COLBERT...EASTERN FRANKLIN AND SOUTHWESTERN LAWRENCE COUNTIES UNTIL 400 PM CDT... At 335 PM CDT, Doppler radar was tracking a strong thunderstorm near Phil Campbell, moving north at 40 mph. Wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Russellville, Phil Campbell, Littleville, Mt Hope, New Bethel, La Grange, Tharptown, Rockwood, Newburg and Crooked Oak. PRECAUTIONARY/PREPAREDNESS ACTIONS... Frequent cloud to ground lightning is occurring with this storm. Lightning can strike several miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3465 8744 3430 8750 3431 8780 3466 8782 TIME...MOT...LOC 2035Z 181DEG 36KT 3432 8764 KTW
Special Weather Statement National Weather Service Huntsville AL 340 PM CDT Thu Aug 27 2020 ALZ001-004-005-272130- Lawrence AL-Lauderdale AL-Limestone AL- 340 PM CDT Thu Aug 27 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN LAUDERDALE...WEST CENTRAL LIMESTONE AND NORTHEASTERN LAWRENCE COUNTIES UNTIL 430 PM CDT... At 340 PM CDT, Doppler radar was tracking a strong thunderstorm near Moulton, moving north at 25 mph. Wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Moulton, Rogersville, Town Creek, Courtland, North Courtland, Hillsboro, Coxey, Oliver, Chalybeate Springs and Red Bank. PRECAUTIONARY/PREPAREDNESS ACTIONS... Frequent cloud to ground lightning is occurring with this storm. Lightning can strike several miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3444 8722 3451 8736 3482 8742 3481 8709 TIME...MOT...LOC 2040Z 182DEG 22KT 3454 8728 KTW
Special Weather Statement
National Weather Service Huntsville AL
348 PM CDT Thu Aug 27 2020
ALZ002-003-272115-
Franklin AL-Colbert AL-
348 PM CDT Thu Aug 27 2020
...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN COLBERT AND
NORTHWESTERN FRANKLIN COUNTIES UNTIL 415 PM CDT...
At 348 PM CDT, Doppler radar was tracking a strong thunderstorm 9
miles east of Tishomingo State Park, moving north at 35 mph.
Wind gusts up to 50 mph will be possible with this storm.
Locations impacted include...
Cherokee, Malone, Mynot, Mt Hester, Margerum and Allsboro.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike several miles away from a thunderstorm. Seek a
safe shelter inside a building or vehicle.
&&
LAT...LON 3481 8811 3481 8795 3452 8797 3456 8808
3470 8812
TIME...MOT...LOC 2048Z 172DEG 30KT 3459 8803
KTWThe Northeast Alabama radar (KHTX), 117 km away, was scanning. The volume nearest the first event began at 20:46 UTC.
13 thunderstorm wind. Local standard time, as filed.
Trees and power lines were knocked down in Courtland.
A trees was knocked down and blocking the westbound lane of Osborn Hill Road at Twin Pines Circle.
A tree was knocked down by thunderstorm winds at 205 Maple Street.
A roof was partially torn off of a business.
A tree was knocked down on North Mulberry Street and East 4th Street.
A tree was knocked down on East 3rd Street and Dover Avenue.
A tree was knocked down at West 5th Street and St. Louis Avenue.
A tree was knocked down at Alabama Avenue and Ridge Point Drive.
Two light poles and part of a tree were knocked down at Wildwood Park prompting its closure.
Trees were knocked down in Anderson.
Multiple trees were knocked down in Fyffe.
Trees were knocked down in St Florian.
Trees were knocked down in Underwood.
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: 918049, 918050, 918051, 918052, 918053, 918054, 918055, 918062, 918060, 918056, 918057, 918058, 918059.