Tornado Watch 160

Issued

Apr 13, 2012, 1:28 PM CDT (18:28 UTC)

Expired

Apr 13, 2012, 9:00 PM CDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

3 in

Strongest gust expected

60 kt

The Altus AFB radar (KFDR), 98 km from the middle of the area, began a volume at 18:31 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.

Two or more tornadoes

40%

One or more EF2 to EF5 tornadoes

30%

Ten or more severe wind reports

40%

One or more gusts of 65 knots or more

10%

Ten or more severe hail reports

60%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 507Apr 13, 12:10 PM CDT
• Mesoscale Discussion 510Apr 13, 3:39 PM CDT
• Mesoscale Discussion 512Apr 13, 5:47 PM CDT
• Mesoscale Discussion 514Apr 13, 7:35 PM CDT

309 
WWUS20 KWNS 131832
SEL0
SPC WW 131832
OKZ000-TXZ000-140200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 160
NWS STORM PREDICTION CENTER NORMAN OK
130 PM CDT FRI APR 13 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

       OKLAHOMA
       A SMALL PART OF NORTHWEST TEXAS

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 130 PM UNTIL 900
PM CDT.

TORNADOES...HAIL TO 3 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 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 35 MILES WEST OF WICHITA FALLS
TEXAS TO 20 MILES NORTH NORTHWEST OF PONCA CITY OKLAHOMA.  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.

DISCUSSION...STORMS ARE BEGINNING TO DEVELOP OVER SWRN OK AS THE CAP
HAS WEAKENED WITHIN A STRONGLY UNSTABLE ENVIRONMENT WITH MLCAPE OF
2000-2500 J/KG.  ALTHOUGH DYNAMIC FORCING FOR LARGE SCALE ASCENT IS
SUBTLE...NUMERICAL GUIDANCE INDICATES THAT STORMS WILL CONTINUE TO
DEVELOP TOWARD NRN OK THIS AFTERNOON...WITH CONVECTIVE POTENTIAL
ALSO INCREASING ALONG THE NWRN EDGE OF MOISTURE AS IT RETREATS NWWD
LATER THIS AFTERNOON AND EVENING.  DEEP LAYER SHEAR OF 40 KT IN THE
LOWEST 6 KM WILL FAVOR FORMATION OF SUPERCELL STRUCTURES...WITH AN
INITIAL THREAT FOR LARGE HAIL AND STRONG WIND GUSTS.  WITH
TIME...LOW LEVEL WINDS/SHEAR WILL STRENGTHEN WITH A SUBSEQUENT
INCREASE IN TORNADO POTENTIAL LATER THIS AFTERNOON AND EVENING.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 23025.


...WEISS

Tornado Watches in Oklahoma, 2012Tornado Watches in Texas, 2012Every tornado watch in 2012

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.