A strong mid level short wave trough passed through central Alabama during the afternoon and evening hours. The air mass was very unstable with CAPE values 4000-4500 J/kg, which resulted in numerous reports of damaging winds.
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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 BMX wrote it up.
A strong mid level short wave trough passed through central Alabama during the afternoon and evening hours. The air mass was very unstable with CAPE values 4000-4500 J/kg, which resulted in numerous reports of damaging winds.
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 Birmingham, AL wrote its last area forecast discussion before the first event at Aug 27, 3:04 PM CST, 17 minutes earlier.
Area Forecast Discussion National Weather Service Birmingham AL 404 PM CDT Tue Aug 27 2019 .SHORT TERM... /Updated at 0349 PM CDT Tue Aug 27 2019/ Thunderstorms have developed across northwest Alabama ahead of an outflow boundary. The HRRR model has been forecasting this development since early this morning and has the activity pushing southeast through the I-20/59 corridor during the late afternoon and early evening hours. The most unstable air mass was located across west Alabama where surface dewpoints were in the middle to upper 70s and surface based CAPE values near 4500 J/kg. The limiting factor is an axis of minimum DCAPE (<1000) across the same area. This will hinder downdraft potential, and so far there have been no reports of significant wind. Since the activity is more surface based with little upper level support, expect a significant decrease in areal coverage by 8 pm. Any remaining activity should be south of I-20 by 9 pm, with only isolated showers after midnight. 58/rose .LONG TERM... /Updated at 0322 AM CDT Tue Aug 27 2019/ Wednesday through Tuesday. The cold front finally pushes through Central AL on Wednesday. I think it will be mostly south of our area by the late morning/early afternoon, but we might see some lingering shower activity associated with the frontal forcing along the far southern counties tomorrow afternoon. This should diminish by the evening with drier, northerly flow pushing in. High pressure builds in Thursday morning, leading to mostly clear skies. Dewpoints will be in the upper 50s to low 60s by Thursday morning, which in conjunction with mostly clear skies, will allow temperatures to drop into the low to mid 60s for much of Central AL both Thursday morning and Friday morning. Later Friday morning, the center of the high pressure has shifted eastward over the Central Appalachians. This will lead wedging with winds becoming more easterly across Central AL. A moisture boundary will slide east to west through the day on Friday. This likely won't have much immediate impact to our sensible weather, but the increased moisture could limit our morning lows for Saturday to the upper 60s to low 70s. The easterly flow becomes more important over the weekend and into early next week. By Saturday evening, Tropical Storm Dorian is forecast by NHC to be in the northern portions of the Bahamas, and just off the southeastern coast of Florida. While we won't see any direct impacts from Dorian through the next 7 days in Central AL, the tropical moisture is expected to lift northwestward due to the easterly flow. Model guidance varies substantially on just how far north that moisture gets this weekend, so I'll keep PoPs on the lower side (20-40%) through early next week due to the overall uncertainty. 25/Owen && .AVIATION... 18Z TAF Discussion. Deep moisture and weak lift will result in widespread cloud cover with cigs 3-5k feet agl and lcl MVFR cigs thru 20z. Sct showers will impact KANB thru 21z, with more organized convection expected across central Alabama between 21z and 02z. A line of storms will likely develop over nw Alabama arnd 20z, and track quickly southeast. The line will weaken as it approaches the I-85 corridor. The storms will produce vsbys blo 3 miles and wind gusts 30-35 kts. Overall convective activity will diminish by 02z, but sct shwrs will continue overnight at KMGM and KTOI. A cold front will bring north winds and drier air into north Alabama by 12z, with any pcpn shifting into south Alabama after 12z. Expect low cigs and fog to develop across south Alabama after 06z ahead of the advancing cold front. 58/rose && .FIRE WEATHER... Rain chances remain elevated within a moist airmass, with light rain or drizzle possible early Tuesday morning. Low clouds and fog should be expected across the area this morning. Scattered to numerous coverage is expected through the day ahead of an approaching cold front. A few thunderstorms will be possible. With the increased moisture, minimum relative humidity values will be elevated as well through tonight. A surface frontal boundary is expected to move into through the area tonight. Although drier air will arrive, minimum relative humidity values for the end of the week should still remain above critical levels, with drier conditions for the end of the week. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 70 88 62 88 61 / 50 10 0 0 0 Anniston 71 89 63 89 63 / 50 10 0 0 0 Birmingham 72 89 64 90 65 / 40 10 0 0 0 Tuscaloosa 73 89 64 89 63 / 40 10 0 0 0 Calera 71 89 63 90 63 / 50 10 0 0 0 Auburn 72 89 67 90 68 / 30 10 0 0 0 Montgomery 74 91 67 92 68 / 40 20 0 0 0 Troy 72 90 67 92 67 / 30 20 0 0 0 && .BMX WATCHES/WARNINGS/ADVISORIES/... None. &&
Hazardous Weather Outlook National Weather Service Birmingham AL 429 AM CDT Tue Aug 27 2019 ALZ011>015-017>050-281230- Marion-Lamar-Fayette-Winston-Walker-Blount-Etowah-Calhoun-Cherokee- Cleburne-Pickens-Tuscaloosa-Jefferson-Shelby-St. Clair-Talladega- Clay-Randolph-Sumter-Greene-Hale-Perry-Bibb-Chilton-Coosa-Tallapoosa- Chambers-Marengo-Dallas-Autauga-Lowndes-Elmore-Montgomery-Macon- Bullock-Lee-Russell-Pike-Barbour- 429 AM CDT Tue Aug 27 2019 This Hazardous Weather Outlook is for the counties served by the National Weather Service office in Birmingham. .DAY ONE...Outlook through Tonight. No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Activation of storm spotters and emergency management is not expected at this time.
Special Weather Statement
National Weather Service Birmingham AL
356 PM CDT Tue Aug 27 2019
ALZ014-272130-
Winston AL-
356 PM CDT Tue Aug 27 2019
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN WINSTON COUNTY UNTIL
430 PM CDT...
At 355 PM CDT, Doppler radar was tracking a strong thunderstorm near
Arley, moving southeast at 20 mph.
Dime size hail and winds in excess of 40 mph will be possible with
this storm.
Locations impacted include...
Arley, Addison, Nesmith, Helicon, Smith Lake, Houston, Addison Town
Hall, Mill Branch, Panther Branch, Bull Branch, Hidden Cove
Campground, Addison Municipal Airport, Cutoff Branch and Yellow
Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3421 8711 3401 8711 3409 8727 3413 8731
3425 8725
TIME...MOT...LOC 2055Z 302DEG 18KT 3414 8723
61The Birmingham radar (KBMX), 74 km away, was scanning. The volume nearest the first event began at 21:21 UTC.
18 thunderstorm wind. Local standard time, as filed.
Several trees uprooted and power lines downed on Hill Road.
Several trees uprooted between Johnson Drive and Thed Brasfield Road.
Several trees uprooted along Union Chapel Road.
A few trees uprooted west of the town of Blountsville.
Several trees uprooted along Highway 79 near the town of Cleveland.
Several trees uprooted in the city of Oneonta.
Several trees uprooted along Kicker Road.
Numerous trees uprooted near the St. Clair county line.
Numerous trees uprooted near the St. Clair county line.
Several trees uprooted and power lines downed in the town of Moundville.
Several trees uprooted along exit 86 on Interstate 20/59.
Numerous trees reported across northern St. Clair County west of the city of Ashville.
Fire started when power lines were downed in the city of Ashville.
Several trees uprooted and power lines downed in the city of Greensboro.
Several trees uprooted along Mudd Street.
Numerous trees uprooted along County Road 10 south of the town of Newbern.
Several trees uprooted along County Road 39 near the town of Dayton.
Several trees uprooted and power lines downed on Tanglewood Drive.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alabama in 2019Every state in 2019This day in weather historyWarnings in Alabama, August 2019
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: 854235, 854234, 854236, 854238, 854239, 854240, 854237, 854241, 854242, 854244, 854246, 854248, 854251, 854254, 854257, 854255, 854260, 854259.