Alert archive / Florida / Tornado Watches in 2011
Tornado Watch 8
The Storm Prediction Center issued this tornado watch at Jan 25, 2011, 8:03 PM EST for 9 counties in Florida. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 25, 2011, 8:03 PM EST (01:03 UTC)
- Expired
- Jan 25, 2011, 11:51 PM EST
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 60 kt
Counties Broward County, FL, Collier County, FL, Glades County, FL, Hendry County, FL, Indian River County, FL, Martin County, FL, Okeechobee County, FL, Palm Beach County, FL, Saint Lucie County, FL
The radar
The Miami radar (KAMX), 139 km from the middle of the area, began a volume at 01:06 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
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 50%
Warnings issued inside it
5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 25, 8:04 PM EST | Severe Thunderstorm Warning | MLB | Indian River, Okeechobee, Saint Lucie | 56 min |
| Jan 25, 8:12 PM EST | Tornado Warning | MLB | Indian River, Okeechobee, Saint Lucie | 63 min |
| Jan 25, 8:36 PM EST | Tornado Warning | MLB | Martin, Okeechobee, Saint Lucie | 54 min |
| Jan 25, 10:23 PM EST | Severe Thunderstorm Warning | MFL | Broward, Palm Beach | 37 min |
| Jan 25, 11:00 PM EST | Severe Thunderstorm Warning | MFL | Broward, Miami-Dade | 45 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
Miami, FL (KMFL), launched 00:00Z, 1.1 hours before the alert went out and 119 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
- 1046 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 569 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 201 m²/s²
- 0-3 km storm-relative helicity
- 276 m²/s²
- Significant tornado parameter
- 1.3
- Supercell composite
- 8.2
The text
As transmitted, in the capitals the NWS used until 2016.
645
WWUS20 KWNS 260058
SEL8
SPC WW 260058
FLZ000-CWZ000-260500-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 8
NWS STORM PREDICTION CENTER NORMAN OK
800 PM EST TUE JAN 25 2011
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
EAST CENTRAL AND SOUTH FLORIDA
COASTAL WATERS
EFFECTIVE THIS TUESDAY NIGHT FROM 800 PM UNTIL MIDNIGHT EST.
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 50 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 35 MILES NORTH NORTHEAST OF
WEST PALM BEACH FLORIDA TO 10 MILES SOUTH SOUTHWEST OF NAPLES
FLORIDA. 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 7...
DISCUSSION...LINE OF SEVERE STORMS CONTINUES TO TRACK EASTWARD
ACROSS THE FL PENINSULA THIS EVENING. LOW LEVEL AND DEEP LAYER
VERTICAL SHEAR REMAINS FAVORABLE FOR EMBEDDED SUPERCELLS ALONG THE
LINE...WITH A RISK OF DAMAGING WINDS AND TORNADOES. LINE IS
EXPECTED TO WEAKEN AND MOVE OFFSHORE BY 05Z.
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 25035.
...HARTSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 25, 7:20 PM EST | Mesoscale Discussion | SPC | Brevard, Charlotte, Collier, DeSoto, Glades, Hendry and 7 more | 55 min |
| Jan 25, 9:51 PM EST | Mesoscale Discussion | SPC | Broward, Miami-Dade, Palm Beach | 54 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.