Tornado Watch 499

Issued

Sep 9, 2014, 3:34 PM CDT (20:34 UTC)

Expired

Sep 9, 2014, 11:55 PM CDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

65 kt

The Grand Island radar (KUEX), 85 km from the middle of the area, began a volume at 20:36 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

40%

Ten or more severe wind reports

70%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

50%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

95%

• Mesoscale Discussion 1694Sep 9, 12:13 PM CDT
• Mesoscale Discussion 1696Sep 9, 3:06 PM CDT
• Mesoscale Discussion 1699Sep 9, 5:06 PM CDT
• Mesoscale Discussion 1701Sep 9, 6:17 PM CDT
• Mesoscale Discussion 1702Sep 9, 6:45 PM CDT
• Mesoscale Discussion 1703Sep 9, 9:00 PM CDT
• Mesoscale Discussion 1705Sep 9, 11:28 PM CDT

020 
WWUS20 KWNS 092047
SEL9  
SPC WW 092047
IAZ000-KSZ000-MOZ000-NEZ000-100500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 499
NWS STORM PREDICTION CENTER NORMAN OK
335 PM CDT TUE SEP 9 2014

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  SOUTHWEST IOWA
  NORTHERN KANSAS
  NORTHWEST MISSOURI
  SOUTHERN AND EASTERN NEBRASKA

* EFFECTIVE THIS TUESDAY AFTERNOON FROM 335 PM UNTIL MIDNIGHT
  CDT.

* PRIMARY THREATS INCLUDE...
  A FEW TORNADOES AND A COUPLE INTENSE TORNADOES POSSIBLE
  SCATTERED DAMAGING WINDS LIKELY WITH ISOLATED SIGNIFICANT GUSTS
    TO 75 MPH POSSIBLE
  SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 2
    INCHES IN DIAMETER POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 50 MILES SOUTHWEST OF
KEARNEY NEBRASKA TO 60 MILES EAST OF SHENANDOAH IOWA.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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...TSTMS EXPECTED TO FORM LATER THIS AFTN THROUGH THIS EVE
ALONG STRENGTHENING W-E WARM FRONT/DIFFERENTIAL HEATING ZONE NEAR
THE NEB-KS BORDER. OTHER STORMS WITH MAINLY A SVR WIND/MARGINAL HAIL
THREAT MAY CONTINUE TO FORM/STRENGTHEN OVER FAR ERN NEB/WRN IA...IN
ZONE OF ASCENT/WAA AHEAD OF WEAKEN ERN NEB UPR IMPULSE.
WHILE MID-LVL WARMING IN WAKE OF ERN NEB UPR IMPULSE CASTS SOME
UNCERTAINTY ON THERMODYNAMIC PROFILES IN WW AREA THIS EVE...ATTM IT
APPEARS THAT COMBINATION OF CONTINUED SFC HEATING...RICH LOW-LVL
MOISTURE...AND EXPECTED STRENGTHENING/TEMPORAL VEERING OF 700 MB
FLOW WILL CREATE ENVIRONMENT FAVORABLE FOR AT LEAST A FEW
SUPERCELLS...ONCE WARM LAYER IS BREACHED BY UPLIFT ALONG BOUNDARY.
OVERALL SETUP APPEARS FAVORABLE FOR A CONDITIONAL RISK FOR TORNADOES
IN ADDITION TO DMGG WIND/SVR HAIL. THE ACTIVITY SHOULD MERGE INTO A
LEWP-BEARING MCS LATER THIS EVE...WITH A CONTINUING RISK FOR DMGG
WIND/TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 25035.


...CORFIDI

Tornado Watches in Nebraska, 2014Tornado Watches in Iowa, 2014Tornado Watches in Missouri, 2014Every tornado watch in 2014

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.