Severe Thunderstorm Watch 511

Issued

Sep 5, 2013, 1:35 PM MDT (19:35 UTC)

Expired

Sep 5, 2013, 9:00 PM MDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

65 kt

The Pendleton radar (KPDT), 131 km from the middle of the area, began a volume at 19:37 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

40%

One or more gusts of 65 knots or more

30%

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

90%

• Mesoscale Discussion 1838Sep 5, 1:06 PM MDT
• Mesoscale Discussion 1840Sep 5, 5:01 PM MDT
• Mesoscale Discussion 1843Sep 5, 6:34 PM MDT
• Mesoscale Discussion 1844Sep 5, 8:13 PM MDT

350 
WWUS20 KWNS 051936
SEL1  
SPC WW 051936
IDZ000-NVZ000-ORZ000-WAZ000-060300-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 511
NWS STORM PREDICTION CENTER NORMAN OK
1235 PM PDT THU SEP 5 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
  NORTHERN AND WESTERN IDAHO
  NORTHEAST NEVADA
  THE EASTERN TWO-THIRDS OREGON
  SOUTHERN WASHINGTON

* EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 1235 PM
  UNTIL 800 PM PDT.

* PRIMARY THREATS INCLUDE...
  SEVERAL DAMAGING WIND GUSTS WITH A FEW SIGNIFICANT GUSTS TO 75
    MPH POSSIBLE
  SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO 2
    INCHES IN DIAMETER POSSIBLE

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 125
STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTHEAST OF
WALLA WALLA WASHINGTON TO 65 MILES SOUTH SOUTHWEST OF ROME
OREGON.  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.

&&

DISCUSSION...THUNDERSTORMS CONTINUE TO GRADUALLY DEVELOP THIS
AFTERNOON ACROSS PORTIONS OF OREGON AND VICINITY...AS AN UPPER LOW
AND ASSOCIATED/POTENT MID-LEVEL SPEED MAX SHIFTS NEWD INTO THE
REGION.  A MOIST LOW-LEVEL AIRMASS CONTINUES TO HEAT/DESTABILIZE
THIS AFTERNOON...WHICH WILL SUPPORT CONTINUED/INCREASINGLY
WIDESPREAD STORM DEVELOPMENT.  GIVEN THE INCREASING FLOW
ALOFT...STORMS WILL ORGANIZE QUICKLY...WITH INITIALLY ROTATING CELLS
POSSIBLY GROWING UPSCALE INTO SMALL-SCALE LINES WITH TIME.  AS
SUCH...LARGE HAIL AND LOCALLY DAMAGING WINDS ARE EXPECTED ACROSS
THIS REGION INTO THE EVENING.

AVIATION...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 500. MEAN STORM
MOTION VECTOR 20040.


...GOSS

Severe Thunderstorm Watches in Idaho, 2013Severe Thunderstorm Watches in Oregon, 2013Severe Thunderstorm Watches in Washington, 2013Every severe thunderstorm 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.