Alert archive / Florida / Tornado Watches in 2011
Tornado Watch 78
The Storm Prediction Center issued this tornado watch at Mar 30, 2011, 4:07 AM CDT for Baldwin County, Escambia County, Alabama; 12 counties in Florida. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 30, 2011, 4:07 AM CDT (09:07 UTC)
- Expired
- Mar 30, 2011, 10:00 AM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
Counties Baldwin County, AL, Escambia County, AL, Bay County, FL, Calhoun County, FL, Escambia County, FL, Franklin County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Liberty County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL
The radar
The Eglin Afb radar (KEVX), 35 km from the middle of the area, began a volume at 09:11 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 70%
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 9.1 hours before the alert went out and 192 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
- -294 J/kg
- Mixed-layer LCL
- 610 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 102 m²/s²
- 0-3 km storm-relative helicity
- 168 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.7
The text
As transmitted, in the capitals the NWS used until 2016.
408
WWUS20 KWNS 300905
SEL8
SPC WW 300905
ALZ000-FLZ000-CWZ000-301500-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 78
NWS STORM PREDICTION CENTER NORMAN OK
405 AM CDT WED MAR 30 2011
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
PARTS OF SOUTHWEST ALABAMA
WESTERN PORTION OF FLORIDA PANHANDLE
COASTAL WATERS
EFFECTIVE THIS WEDNESDAY MORNING FROM 405 AM UNTIL 1000 AM CDT.
TORNADOES...HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTH SOUTHEAST OF
MARIANNA FLORIDA TO 5 MILES WEST NORTHWEST OF MOBILE ALABAMA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU8).
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 76...
DISCUSSION...AIR MASS CONTINUES TO DESTABILIZE EWD AHEAD OF ACTIVE
THUNDERSTORMS MOVING INTO SWRN AL. WITH VEERING SHEAR PROFILES AND
50KT BRN SHEAR...SUPERCELLS ARE LIKELY AS WELL AS SHORT LINE
SEGMENTS AS STORMS CONTINUE EWD ACROSS THE WATCH. TORNADOS WILL BE
POSSIBLE WITH BOTH MODES OF STORMS ALONG WITH WIND DAMAGE.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 27030.
...HALESSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 29, 9:42 PM CDT | Tornado Watch | SPC | Mobile, Washington | 7 hr |
| Mar 29, 10:32 PM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Blount, Butler, Chilton, Choctaw and 27 more | 58 min |
| Mar 30, 1:51 AM CDT | Mesoscale Discussion | SPC | Baldwin, Escambia, Mobile | 114 min |
| Mar 30, 7:28 AM CDT | Mesoscale Discussion | SPC | Alachua, Baker, Bay, Bradford, Calhoun, Clay and 26 more | 2 hr |
| Mar 30, 10:10 AM CDT | Tornado Watch | SPC | Alachua, Baker, Bradford, Brevard, Citrus, Clay and 27 more | 8 hr |
| Mar 30, 2:32 PM CDT | Mesoscale Discussion | SPC | Alachua, Baker, Bradford, Citrus, Clay, Columbia and 17 more | 58 min |
| Mar 30, 3:41 PM CDT | Mesoscale Discussion | SPC | Brevard, Flagler, Orange, Osceola, Polk, Seminole and 1 more | 2 hr |
Nearby
Tornado Watches in Florida, 2011Tornado Watches in Alabama, 2011Every tornado watch in 2011
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.