Tornado Watch 541

Issued

Oct 4, 2013, 6:42 PM CDT (23:42 UTC)

Expired

Oct 5, 2013, 12:00 AM CDT

In force

5 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The Des Moines radar (KDMX), 50 km from the middle of the area, began a volume at 23:43 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

40%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 1934Oct 4, 5:20 PM CDT
• Mesoscale Discussion 1938Oct 4, 10:29 PM CDT

112 
WWUS20 KWNS 042345
SEL1  
SPC WW 042345
IAZ000-050500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 541
NWS STORM PREDICTION CENTER NORMAN OK
645 PM CDT FRI OCT 4 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  WESTERN AND CENTRAL IOWA

* EFFECTIVE THIS FRIDAY NIGHT FROM 645 PM UNTIL MIDNIGHT CDT.

* PRIMARY THREATS INCLUDE...
  SEVERAL TORNADOES WITH A FEW INTENSE TORNADOES POSSIBLE
  SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO 2
    INCHES IN DIAMETER POSSIBLE
  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES EAST AND WEST OF A LINE FROM 65 MILES SOUTH SOUTHWEST OF
DES MOINES IOWA TO 40 MILES WEST NORTHWEST OF MASON CITY IOWA. 
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).

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.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 539...WW 540...

DISCUSSION...DISCRETE SUPERCELLS OVER FAR SWRN AND NWRN PARTS OF IA
ARE EXPECTED TO SPREAD NEWD THIS EVENING...WITH POTENTIAL FOR NEW
STORMS TO DEVELOP ALONG/AHEAD OF AN EWD ADVANCING COLD FRONT
APPROACHING THE MO RIVER.  FAVORABLE INSTABILITY WITH CAPE RANGING
FROM 2500 J/KG IN SRN IA TO NEAR 1000 J/KG IN NRN IA COUPLED WITH
WINDS THAT VEER STRONGLY WITH HEIGHT /REF DMX VAD WIND PROFILE/ WILL
PROMOTE CONTINUATION OF A SUPERCELL/TORNADO THREAT SPREADING TOWARD
CENTRAL IA TONIGHT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 23030.


...WEISS

Tornado Watches in Iowa, 2013Every tornado watch in 2013

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.