Tornado Watch 285

Issued

May 11, 2011, 3:52 PM MDT (21:52 UTC)

Expired

May 11, 2011, 9:35 PM MDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

2.5 in

Strongest gust expected

60 kt

The Goodland radar (KGLD), 22 km from the middle of the area, began a volume at 21:53 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

50%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

30%

One or more gusts of 65 knots or more

10%

Ten or more severe hail reports

80%

One or more hailstones of 2 inches or more

40%

Six or more combined severe hail and wind reports

95%

• Mesoscale Discussion 735May 11, 12:51 PM MDT
• Mesoscale Discussion 748May 11, 6:51 PM MDT

731 
WWUS20 KWNS 112153
SEL5
SPC WW 112153
COZ000-KSZ000-NEZ000-120600-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 285
NWS STORM PREDICTION CENTER NORMAN OK
350 PM MDT WED MAY 11 2011

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

       NORTHEAST COLORADO
       NORTHWEST KANSAS
       SOUTHWEST AND SOUTH CENTRAL NEBRASKA

EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 350 PM UNTIL MIDNIGHT MDT.

TORNADOES...HAIL TO 2.5 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 50 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 75 MILES WEST OF BURLINGTON
COLORADO TO 55 MILES EAST NORTHEAST OF HILL CITY KANSAS.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU5).

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 280...WW 281...WW
282...WW 283...WW 284...

DISCUSSION...TSTMS EXPECTED TO INCREASE IN COVERAGE AND STRENGTH
THROUGH THIS EVE AS EXIT REGION OF JET STREAK/UPR VORT ASSOCIATED
WITH CNTRL RCKYS UPR LOW PIVOTS NNEWD.  LOW LVL CONVERGENCE WILL
MAXIMIZE ALONG W-E FRONT THAT LIKELY WILL BECOME NEARLY STNRY ALONG
MAIN AXIS OF WW.  DEEP EML...AMPLE BOUNDARY LAYER MOISTURE...AND
STRENGTHENING DEEP SHEAR SUGGEST LIKELIHOOD FOR SUPERCELLS WITH
LARGE HAIL AND LOCALLY DMGG WIND...IN ADDITION TO POSSIBLE TORNADOES
IN ZONE OF MAXIMUM LOW LVL DIRECTIONAL SHEAR NEAR FRONT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 20025.


...CORFIDI

Tornado Watches in Kansas, 2011Tornado Watches in Colorado, 2011Tornado Watches in Nebraska, 2011Every tornado watch in 2011

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.