Alert archive / Alabama / Tornado Watches in 2012
Tornado Watch 100
The Storm Prediction Center issued this tornado watch at Mar 22, 2012, 10:55 AM CDT for 6 counties in Alabama. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 22, 2012, 10:55 AM CDT (15:55 UTC)
- Expired
- Mar 22, 2012, 5:00 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 60 kt
Counties Baldwin County, AL, Clarke County, AL, Mobile County, AL, Monroe County, AL, Washington County, AL, Wilcox County, AL
The radar
The Mobile radar (KMOB), 30 km from the middle of the area, began a volume at 15:57 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 30%
- One or more EF2 to EF5 tornadoes
- 10%
- Ten or more severe wind reports
- 20%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 50%
Warnings issued inside it
4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 22, 11:38 AM CDT | Severe Thunderstorm Warning | MOB | Clarke, Washington | 67 min |
| Mar 22, 1:36 PM CDT | Flash Flood Warning | MOB | Clarke, Mobile, Washington | 6 hr |
| Mar 22, 3:45 PM CDT | Flash Flood Warning | MOB | Baldwin, Clarke, Escambia, Mobile, Monroe, Washington | 6 hr |
| Mar 22, 4:25 PM CDT | Severe Thunderstorm Warning | MOB | Wilcox | 50 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 12:00Z, 3.9 hours before the alert went out and 177 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.
- Mixed-layer CAPE
- 2 J/kg
- Mixed-layer CIN
- 0 J/kg
- Mixed-layer LCL
- 438 m above ground
- 0-6 km bulk shear
- 56 kt
- 0-1 km storm-relative helicity
- 148 m²/s²
- 0-3 km storm-relative helicity
- 377 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.3
The text
As transmitted, in the capitals the NWS used until 2016.
874
WWUS20 KWNS 221557
SEL0
SPC WW 221557
ALZ000-CWZ000-222200-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 100
NWS STORM PREDICTION CENTER NORMAN OK
1055 AM CDT THU MAR 22 2012
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
SOUTHWEST ALABAMA
COASTAL WATERS
EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 1055 AM UNTIL
500 PM CDT.
TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 35 STATUTE
MILES EAST AND WEST OF A LINE FROM 45 MILES SOUTH SOUTHEAST OF
MOBILE ALABAMA TO 90 MILES NORTH NORTHEAST OF MOBILE ALABAMA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU0).
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.
OTHER WATCH INFORMATION...CONTINUE...WW 99...
DISCUSSION...BAND OF STRONG STORMS EXTENDING FROM THE GULF OF MEXICO
NNEWD TO NEAR THE SERN MS/SWRN AL BORDER IS EXPECTED TO MOVE SLOWLY
EWD AS CELLS MOVE NNEWD 25-35 KT. ENVIRONMENT REMAINS SUPPORTIVE OF
STORM ROTATION WITH KMOB VAD PROFILE EXHIBITING 30-40 KT VEERING
FLOW IN THE LOWEST 1-3 KM...RESULTING IN 1 KM SHEAR OF 30 KT AND SRH
OF 300 M2/S2 IN THE LOWEST 2-3 KM...WITHIN UNSTABLE THERMODYNAMIC
CONDITIONS WITH MLCAPE OF 500-750 J/KG. THREAT FOR EMBEDDED
SUPERCELLS WILL CONTINUE INTO THE AFTERNOON WITH LOCAL DAMAGING
WINDS AND BRIEF TORNADOES POSSIBLE.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
400. MEAN STORM MOTION VECTOR 20030.
...WEISSSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 22, 2:28 AM CDT | Mesoscale Discussion | SPC | Mobile, Washington | 2 hr |
| Mar 22, 6:49 AM CDT | Mesoscale Discussion | SPC | Mobile | 116 min |
| Mar 22, 9:53 AM CDT | Mesoscale Discussion | SPC | Baldwin, Clarke, Mobile, Washington | 67 min |
| Mar 22, 1:00 PM CDT | Mesoscale Discussion | SPC | Autauga, Baldwin, Bibb, Butler, Chilton, Conecuh and 10 more | 60 min |
| Mar 22, 3:30 PM CDT | Mesoscale Discussion | SPC | Baldwin, Conecuh, Escambia, Mobile, Monroe, Wilcox | 60 min |
Nearby
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.