A weak upper level disturbance and associated surface front moved across Central Alabama on Sunday, August 21. Scattered thunderstorms developed ahead of the short wave, causing isolated 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 BMX wrote it up.
A weak upper level disturbance and associated surface front moved across Central Alabama on Sunday, August 21. Scattered thunderstorms developed ahead of the short wave, causing isolated wind damage. The upper level disturbance quickly moved east of the area, leaving the front to slowly push southward during the day on Monday, August 22. South of this boundary, scattered thunderstorms developed again as a result of mesoscale boundary interactions within a moist and unstable airmass, resulting in isolated 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 Birmingham, AL wrote its last area forecast discussion before the first event at Aug 21, 10:30 AM CST, 3 hours 50 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BIRMINGHAM AL 1130 AM CDT SUN AUG 21 2011 .UPDATE... FOR MORNING WEATHER AND AVIATION DISCUSSIONS. && .DISCUSSION... FORECAST FROM THE MID SHIFT LOOKS LIKE IT IS GREAT SHAPE...WITH ONLY MINOR ADJUSTMENTS TO THE HOURLY TEMPERATURE AND DEWPOINT GRIDS. THE SET UP REMAINS SIMILAR...AS A WEAK FRONTAL BOUNDARY AND ASSOCIATED UPPER LEVEL SHORT WAVE ARE SLOWLY DIGGING ACROSS NORTHERN MISSISSIPPI...WITH SOME AFTERNOON CONVECTION ALREADY BEGINNING TO TAKE SHAPE. WE SHOULD BEGIN TO SEE INCREASED COVERAGE OVER THE CWA WITHIN THE NEXT FEW HOURS. THE SECONDARY BOUNDARY THAT CONTAINS MUCH DRIER AIR IS STILL PARKED UP TO OUR NORTHWEST ACROSS NORTHERN MISSOURI. THIS BOUNDARY WILL BEGIN TO DIG FURTHER SOUTH OVER THE NEXT 24 TO 48 HOURS...AND IS AN IMPORTANT ONE AS IT MAY BE THE KEY PLAYER ON THE TROPICAL INFLUENCES BY MID TO LATE WEEK. && .AVIATION... 18Z TAF DISCUSSION. THERE ARE LITTLE TO NO AVIATION CONCERNS OVER THE NEXT 12 TO 18 HOURS...AS CONDITIONS ARE EXPECTED TO REMAIN VFR. HOWEVER...IF THERE ARE ANY CONCERNS THEY WILL CONTINUE TO FOCUS ON THE AFTERNOON AND EVENING CONVECTION THAT WILL BE POSSIBLE AT ANY GIVEN SITE. AS A WEAK FRONTAL BOUNDARY TRIES TO DIG SOUTH THIS AFTERNOON...FORECASTS HAVE AN INCREASED POTENTIAL FOR AFTERNOON AND EVENING CONVECTION. AT THE TIME OF ISSUANCE THE BOUNDARY IS CURRENTLY MOVING SOUTHEAST THROUGH NORTHERN MISSISSIPPI...WITH CONVECTION ALREADY BEGINNING. OTHERWISE...THERE COULD BE SOME BRIEF SHALLOW GROUND FOG DURING THE VERY EARLY MORNING HOURS DEPENDING ON THE AMOUNT OF RAIN AND OVERNIGHT CLOUD COVER. && .BMX WATCHES/WARNINGS/ADVISORIES... NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE BIRMINGHAM AL 936 AM CDT SUN AUG 21 2011 ALZ011>015-017>050-221445- 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- 936 AM CDT SUN AUG 21 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE COUNTIES SERVED BY THE NATIONAL WEATHER SERVICE OFFICE IN BIRMINGHAM. .DAY ONE...THIS AFTERNOON AND TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. 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
242 PM CDT SUN AUG 21 2011
ALZ035-212030-
CHILTON AL-
242 PM CDT SUN AUG 21 2011
...SIGNIFICANT WEATHER ADVISORY FOR EASTERN CHILTON COUNTY UNTIL 330
PM CDT...
AT 240 PM CDT...THE NATIONAL WEATHER SERVICE WAS TRACKING A STRONG
THUNDERSTORM NEAR CLANTON. THIS STORM WAS NEARLY STATIONARY.
WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THIS STORM.
LOCATIONS IN OR NEAR THE PATH OF THIS STORM INCLUDE...
VERBENA...
COOPER...
ENTERPRISE...
&&
LAT...LON 3281 8672 3290 8653 3275 8640 3271 8641
3271 8667
TIME...MOT...LOC 1942Z 330DEG 2KT 3283 8663
17/KLAWSThe Birmingham radar (KBMX), 51 km away, was scanning. The volume nearest the first event began at 20:21 UTC.
3 thunderstorm wind, 1 hail. Local standard time, as filed.
Numerous trees were knocked down across south central Chilton county, blocking several county roads, including County Road 24, County Road 47, County Road 7 and County Road 49. In addition, the metal roof of several mobile homes along County Road 24 was partially removed.
Several trees were knocked down along Pinedale Rd and the surrounding area.
A couple large trees and power lines were knocked down in and around the Amazing Grace Mobile Home Park. In addition, the underpinning of several mobile homes sustained damage. A trampoline was blown several lots down and into the side of a mobile home, its legs puncturing the exterior wall of the mobile home.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alabama in 2011Every state in 2011This day in weather historyWarnings in Alabama, August 2011
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: 345217, 345218, 345220, 345219.