Alert archive / Alabama / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 32, NWS Birmingham, AL

March 18, 2013St. Clair County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Mar 18, 2013, 3:03 PM CDT for St. Clair County, Alabama. It was in force for 27 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Mar 18, 2013, 3:03 PM CDT (20:03 UTC)
Expired: Mar 18, 2013, 3:30 PM CDT
In force: 27 min
Issued by: NWS Birmingham, AL
Area: Storm-based polygon

County St. Clair County, AL

The radar

The Birmingham radar (KBMX), 62 km from the middle of the area, began a volume at 20:04 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Mar 18, 3:33 PM CDT	TSTM WND DMG	4 Ne Leeds, AL	COUPLE PINE TREES SNAPPED AND POWERLINES DOWN ALONG RIDGEWOOD DRIVE. TIME ESTIMATED FROM RADAR.
Mar 18, 3:34 PM CDT	TSTM WND DMG	Moody, AL	NUMEROUS TREES DOWN IN THE 1600 BLOCK OF PARK AVENUE AND ACTON ROAD.
Mar 18, 3:35 PM CDT	TSTM WND DMG	Odenville, AL	DOWNED TREES ACROSS THE COUNTY. ALABAMA HWY 171 WAS BLOCKED FOR 30 MINUTES DUE TO TREES DOWN.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Mar 18, 1:31 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 8.1 hours before the alert went out and 61 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 196 J/kg
Mixed-layer CIN: -139 J/kg
Mixed-layer LCL: 520 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 298 m²/s²
0-3 km storm-relative helicity: 281 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

557 
WUUS54 KBMX 182003
SVRBMX
ALC115-182030-
/O.NEW.KBMX.SV.W.0032.130318T2003Z-130318T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
303 PM CDT MON MAR 18 2013

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN ST. CLAIR COUNTY IN ALABAMA...

* UNTIL 330 PM CDT

* AT 259 PM CDT...THE NATIONAL WEATHER SERVICE INDICATED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING
  WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  TRUSSVILLE...AND MOVING EAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MOODY...ODENVILLE...BALD ROCK...BRANCHVILLE...CHULA VISTA AND
  WATTSVILLE.

THIS INCLUDES...
INTERSTATE 20 EXIT NUMBERS 144 THROUGH 158...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS.

&&

TO REPORT SEVERE WEATHER...
CALL 1-800-856-0758 OR TWEET YOUR REPORT USING HASHTAG ALWX

LAT...LON 3375 8621 3361 8621 3356 8648 3356 8655
      3362 8655 3364 8654 3365 8654 3367 8652
TIME...MOT...LOC 2003Z 260DEG 35KT 3360 8654

$$

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Mar 18, 12:30 PM CDT, 2 hours 33 minutes earlier.

Area forecast discussion, Mar 18, 12:30 PM CDT, 2 hours 33 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1230 PM CDT MON MAR 18 2013

.UPDATE...
FOR 18Z AVIATION.

&&

.DISCUSSION...

TODAY LOOKS LIKE IT COULD BE THE STORY OF 2 OR 3 DIFFERENT TALES.
WE START OUT THIS MORNING WITH AMPLE CLOUD COVER AND SCATTERED
SHOWERS ACROSS A LARGE PORTION OF CENTRAL ALABAMA AS WELL AS THE
MAIN ONGOING SITUATION...THE SQUALL LINE THAT HAS DEVELOPED IN
NORTHEAST MISSISSIPPI. AS EXPECTED...THE MORNING CLOUD COVER IS
HAMPERING THE DEVELOPMENT OF SFC BASED INSTABILITY...BUT THE SQUALL
LINE DOES HAVE THE ENERGY FROM THE PARENT SURFACE LOW IN SOUTHERN
KENTUCKY WITH WHICH TO WORK.  THE LINE SHOULD REMAIN ELEVATED BUT
WILL CARRY A LOW-END HAIL AND DAMAGING WIND THREAT.   THIS IS
EXPECTED TO CHANGE HOWEVER AS WE MOVE INTO THE AFTERNOON HOURS.
MODEL GUIDANCE SUPPORTED BY WATER VAPOR SATELLITE IMAGERY ARE STILL
SUGGESTING DRY AIR WILL WORK INTO CENTRAL ALABAMA ALOFT AND WE COULD
STILL SEE SOME MIXING OUT OF THE CLOUDS CURRENTLY IN PLACE.  IF THIS
DOES OCCUR...A GOOD PORTION OF THE AREA COULD SEE SFC BASED CAPES IN
THE 1000-1750 J/KG RANGE.  WHEN COUPLED WITH INCREASING MID-LEVEL
LAPSE RATES AND VEERING SURFACE WINDS...THIS COMBINATION COULD SPELL
SOME FAIRLY LARGE HAIL AND POTENTIALLY DAMAGING WINDS WITH ANY STORM
THAT TAPS INTO THAT ENERGY.  IF YOU DO SEE CLEARING IN YOUR AREA AND
THE SUN COMES OUT...THEN THAT WILL INCREASE YOUR CHANCE FOR A SEVERE
THUNDERSTORM WATCH TO BE EXTENDED TO YOU AS THE ENVIRONMENT WILL
RIPEN FOR SEVERE POTENTIAL THIS AFTERNOON AND EVENING. PROPER
ENVIRONMENTAL CONDITIONS FOR SEVERE WEATHER ARE EXPECTED TO DECREASE
AS WE MOVE TOWARDS THE MIDNIGHT HOUR TONIGHT.

UPDATES ARE OUT.

27

&&

.AVIATION...
18Z TAF DISCUSSION.

THIS IS GOING TO BE A VERY IDEALIZED TAF FORECAST...ESPECIALLY FOR
THE FIRST 6 TO 8 HOURS.  WITH MVFR CIGS BECOMING THINNER AND
THINNER...SUNSHINE IS STARTING TO SQUEEZE THROUGH THE CLOUD DECK.
THIS WILL LIKELY HELP TO DESTABILIZE THINGS...ALLOWING FOR SCATTERED
TS DEVELOPMENT ACROSS MOST OF THE AREA THIS AFTERNOON.  PREVAILING
TAF LINES REALLY REVOLVE AROUND THE LINE OF TS OVER NORTHERN
MISSISSIPPI AND ALABAMA...WHICH WILL CONTINUE PUSHING TO THE SOUTH
AND EAST THROUGH 00Z.  MAY HAVE TO ADJUST A BIT IF THESE SCATTERED
STORMS BEGIN POPPING UP AHEAD OF THE LINE.

WINDS WILL GRADUALLY VEER THROUGH THE AFTERNOON AS WELL...GIVING US
SOUTHWESTERLY SURFACE FLOW AHEAD OF FROPA...WHICH WILL TRANSLATE
THROUGH CENTRAL ALABAMA DURING THE OVERNIGHT HOURS.  CLEARING IS
LIKELY A FEW HOURS AFTER DAYBREAK ON TUESDAY.

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

Hazardous weather outlook, Mar 18, 1:08 PM CDT, 1 hour 55 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
108 PM CDT MON MAR 18 2013

ALZ011>015-017>050-191815-
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-
108 PM CDT MON MAR 18 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE COUNTIES SERVED BY THE
NATIONAL WEATHER SERVICE OFFICE IN BIRMINGHAM.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THERE WILL BE A CHANCE FOR SEVERE THUNDERSTORMS THROUGH 10 PM...
FOR ALL OF CENTRAL ALABAMA. THE PRIMARY THREATS WILL BE DAMAGING
STRAIGHT LINE WINDS AND LARGE HAIL...POSSIBLY UP TO TWO INCHES IN
DIAMETER.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

A DRY AIRMASS WILL WORK INTO THE AREA ON TUESDAY. THERE IS A LOW
CONFIDENCE THAT RELATIVE HUMIDITIES MAY DROP BELOW 25 PERCENT
ACROSS THE EAST FOR SEVERAL HOURS DURING THE AFTERNOON. THIS WOULD
HELP CREATE A POTENTIAL HIGH FIRE DANGER. OUTDOOR BURNING IS
DISCOURAGED WITH THIS TYPE OF AIRMASS.

THERE IS A CHANCE FOR TEMPERATURES TO FALL BELOW THE FREEZING MARK
WEDNESDAY NIGHT INTO THURSDAY MORNING. SENSITIVE VEGETATION WILL
NEED TO BE PROTECTED DUE TO THE FREEZING TEMPERATURES.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT WILL BE
NEEDED THIS AFTERNOON AND TONIGHT.

27

In the hours before

Local storm report, Mar 18, 2:32 PM CDT, 31 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
232 PM CDT MON MAR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0224 PM     TSTM WND DMG     MILLPORT                33.56N 88.08W
03/18/2013                   LAMAR              AL   EMERGENCY MNGR

            TREES AND POWER LINES DOWN

&&

SUNGER

Local storm report, Mar 18, 2:35 PM CDT, 28 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
235 PM CDT MON MAR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0225 PM     TSTM WND DMG     FAYETTE                 33.69N 87.83W
03/18/2013                   FAYETTE            AL   EMERGENCY MNGR

            TREES DOWN IN TOWN

&&

SUNGER

Local storm report, Mar 18, 2:41 PM CDT, 22 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
241 PM CDT MON MAR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0227 PM     TSTM WND DMG     LYNN                    34.04N 87.55W
03/18/2013                   WINSTON            AL   BROADCAST MEDIA

            TREES DOWN AND TRANSFORMERS BLOWN IN TOWN.

&&

SUNGER

Local storm report, Mar 18, 2:43 PM CDT, 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
243 PM CDT MON MAR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0226 PM     TSTM WND DMG     FAYETTE                 33.69N 87.83W
03/18/2013                   FAYETTE            AL   EMERGENCY MNGR

            TREES DOWN ACROSS HWY 171 NEAR THE INTERSECTION OF HWY
            159 ON THE SOUTH END OF TOWN.

&&

SUNGER

Local storm report, Mar 18, 2:52 PM CDT, 11 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
252 PM CDT MON MAR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0218 PM     TSTM WND DMG     HALEYVILLE              34.24N 87.62W
03/18/2013                   WINSTON            AL   TRAINED SPOTTER

            TREES AND POWER LINES DOWN THROUGHOUT TOWN. SOME BUILDING
            DAMAGE BUT UNKNOWN QUANTITY AT THIS TIME.

&&

SUNGER

Local storm report, Mar 18, 2:55 PM CDT, 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
255 PM CDT MON MAR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0246 PM     TSTM WND DMG     CURRY                   33.96N 87.21W
03/18/2013                   WALKER             AL   EMERGENCY MNGR

            TREES AND POWER LINES DOWN

&&

SUNGER

The office that day

Everything else NWS Birmingham, AL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 18, 4:58 AM CDT	Special Weather Statement	BMX	Marion	32 min
Mar 18, 1:06 PM CDT	Special Weather Statement	BMX	Marion	39 min
Mar 18, 1:19 PM CDT	Severe Thunderstorm Warning	BMX	Marion	41 min
Mar 18, 1:31 PM CDT	Severe Thunderstorm Warning	BMX	Marion	44 min
Mar 18, 1:51 PM CDT	Severe Thunderstorm Warning	BMX	Lamar, Marion	54 min
Mar 18, 2:06 PM CDT	Severe Thunderstorm Warning	BMX	Winston	39 min
Mar 18, 2:18 PM CDT	Severe Thunderstorm Warning	BMX	Fayette, Lamar, Marion, Pickens, Winston	57 min
Mar 18, 2:28 PM CDT	Severe Thunderstorm Warning	BMX	Tuscaloosa, Walker	62 min
Mar 18, 3:06 PM CDT	Severe Thunderstorm Warning	BMX	Blount, Jefferson	39 min
Mar 18, 3:20 PM CDT	Special Weather Statement	BMX	Greene, Sumter	55 min
Mar 18, 3:28 PM CDT	Severe Thunderstorm Warning	BMX	Tuscaloosa	47 min
Mar 18, 3:34 PM CDT	Severe Thunderstorm Warning	BMX	Etowah, St. Clair, Shelby	56 min
Mar 18, 3:38 PM CDT	Severe Thunderstorm Warning	BMX	Chilton, Coosa	52 min
Mar 18, 3:46 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun, Talladega	44 min
Mar 18, 3:54 PM CDT	Severe Thunderstorm Warning	BMX	Bibb, Chilton	66 min
Mar 18, 4:01 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun, Cherokee, Talladega	59 min
Mar 18, 4:09 PM CDT	Severe Thunderstorm Warning	BMX	Chambers, Tallapoosa	66 min
Mar 18, 4:12 PM CDT	Severe Thunderstorm Warning	BMX	Clay, Cleburne, Randolph	63 min
Mar 18, 4:14 PM CDT	Severe Thunderstorm Warning	BMX	Coosa	31 min
Mar 18, 4:18 PM CDT	Severe Thunderstorm Warning	BMX	Bibb, Chilton, Perry	57 min
Mar 18, 4:24 PM CDT	Special Weather Statement	BMX	Russell	36 min
Mar 18, 4:35 PM CDT	Severe Thunderstorm Warning	BMX	Tallapoosa	55 min
Mar 18, 4:43 PM CDT	Special Weather Statement	BMX	Dallas, Marengo, Perry	62 min
Mar 18, 4:49 PM CDT	Severe Thunderstorm Warning	BMX	Dallas, Marengo, Perry, Sumter	56 min
Mar 18, 4:58 PM CDT	Severe Thunderstorm Warning	BMX	Autauga, Elmore	62 min
Mar 18, 5:05 PM CDT	Severe Thunderstorm Warning	BMX	Tallapoosa	40 min
Mar 18, 5:18 PM CDT	Severe Thunderstorm Warning	BMX	Chambers, Lee	57 min
Mar 18, 5:30 PM CDT	Special Weather Statement	BMX	Lowndes, Montgomery	60 min
Mar 18, 5:32 PM CDT	Severe Thunderstorm Warning	BMX	Macon	58 min
Mar 18, 5:38 PM CDT	Severe Thunderstorm Warning	BMX	Russell	52 min
Mar 18, 6:11 PM CDT	Special Weather Statement	BMX	Lowndes, Montgomery	49 min
Mar 18, 6:15 PM CDT	Severe Thunderstorm Warning	BMX	Lee	15 min
Mar 18, 6:21 PM CDT	Special Weather Statement	BMX	Barbour, Bullock, Pike, Russell	54 min
Mar 18, 6:52 PM CDT	Severe Thunderstorm Warning	BMX	Barbour, Bullock, Pike	53 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2013 Every severe thunderstorm warning in 2013

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.