Severe Thunderstorm Watch 511

Issued

Sep 17, 2015, 6:38 PM CDT (23:38 UTC)

Expired

Sep 18, 2015, 1:00 AM CDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

2.5 in

Strongest gust expected

60 kt

The Pleasant Hill radar (KEAX), 159 km from the middle of the area, began a volume at 23:41 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

10%

One or more EF2 to EF5 tornadoes

2%

Ten or more severe wind reports

30%

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

60%

• Mesoscale Discussion 1811Sep 17, 5:47 PM CDT
• Mesoscale Discussion 1813Sep 17, 10:12 PM CDT

175 
WWUS20 KWNS 172336
SEL1  
SPC WW 172336
IAZ000-KSZ000-MOZ000-NEZ000-180600-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 511
NWS STORM PREDICTION CENTER NORMAN OK
635 PM CDT THU SEP 17 2015

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
  SOUTHERN IOWA
  NORTHEASTERN KANSAS
  NORTHERN MISSOURI
  EXTREME SOUTHEASTERN NEBRASKA

* EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 635 PM
  UNTIL 100 AM CDT.

* PRIMARY THREATS INCLUDE...
  SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 2.5
    INCHES IN DIAMETER POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

SUMMARY...SEVERE THUNDERSTORMS ARE EXPECTED TO BECOME MORE
CONCENTRATED DURING THE NEXT FEW HOURS AS ACTIVITY SHIFTS EASTWARD
ACROSS THE MISSOURI VALLEY AND OVER MORE OF THE WATCH AREA. 
DAMAGING GUSTS AND LARGE HAIL ARE EXPECTED.  FOR METEOROLOGICAL
DETAILS...SEE SPC MESOSCALE DISCUSSION 1811.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80
STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES SOUTH
SOUTHWEST OF SAINT JOSEPH MISSOURI TO 45 MILES NORTH NORTHEAST OF
LAMONI IOWA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

&&

AVIATION...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 550. MEAN STORM
MOTION VECTOR 27025.


...EDWARDS

Severe Thunderstorm Watches in Missouri, 2015Severe Thunderstorm Watches in Iowa, 2015Severe Thunderstorm Watches in Kansas, 2015Every severe thunderstorm watch in 2015

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.