Tornado Watch 415

Issued

Jul 15, 2013, 2:48 PM MDT (20:48 UTC)

Expired

Jul 15, 2013, 11:00 PM MDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

4 in

Strongest gust expected

65 kt

The Glasgow radar (KGGW), 215 km from the middle of the area, began a volume at 20:51 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

30%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

60%

One or more hailstones of 2 inches or more

50%

Six or more combined severe hail and wind reports

90%

• Mesoscale Discussion 1401Jul 15, 1:51 PM MDT
• Mesoscale Discussion 1402Jul 15, 4:39 PM MDT
• Mesoscale Discussion 1403Jul 15, 6:27 PM MDT
• Mesoscale Discussion 1404Jul 15, 8:57 PM MDT

918 
WWUS20 KWNS 152056
SEL5  
SPC WW 152056
MTZ000-NDZ000-160500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 415
NWS STORM PREDICTION CENTER NORMAN OK
250 PM MDT MON JUL 15 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  EASTERN MONTANA
  WESTERN AND NORTHERN NORTH DAKOTA

* EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 250 PM UNTIL
  1100 PM MDT.

* PRIMARY THREATS INCLUDE...
  SEVERAL TORNADOES WITH A FEW INTENSE TORNADOES POSSIBLE
  SEVERAL VERY LARGE HAIL EVENTS TO 4 INCHES IN DIAMETER POSSIBLE
  SEVERAL DAMAGING WIND GUSTS WITH A FEW SIGNIFICANT GUSTS TO 75
    MPH POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 100 STATUTE
MILES EAST AND WEST OF A LINE FROM 60 MILES NORTH NORTHEAST OF
WILLISTON NORTH DAKOTA TO 50 MILES SOUTH SOUTHEAST OF BAKER
MONTANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).

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...SFC-BASED TSTMS EXPECTED TO FORM IN THE NEXT HOUR OR SO
ALONG LEE TROUGH IN ERN MT...AND POSSIBLY ALONG COLD FRONT IN THE NE
PART OF THE STATE. DEVELOPMENT WILL BE FOSTERED BY CONTINUED SFC
HEATING...LOW-LVL MOISTURE INFLOW...ASCENT ASSOCIATED BOTH MAIN UPR
IMPULSE MOVING ENE FROM SRN AB...AND BY UPLIFT WITH WEAKER
DISTURBANCE MOVING ENE FROM SW MT/NW WY.
DEEP EML ATOP FAIRLY RICH LOW-LVL MOISTURE /PW AROUND 1 INCH/ IN
MODERATELY TO STRONGLY SHEARED ENVIRONMENT COULD YIELD STORMS WITH
VERY LARGE HAIL AND BOWING SEGMENTS WITH HIGH WIND. SOME RISK ALSO
WILL EXIST FOR TORNADOES...ESPECIALLY IN NERN MT AND NW ND...WHERE
LOW-LVL WINDS ARE LIKELY TO REMAIN SOMEWHAT BACKED...TEMP-DEW POINT
SPREADS WILL BE SMALLEST...AND DEEP SHEAR GREATEST. ACTIVITY MAY
EVOLVE INTO A SQLN WITH EMBEDDED LEWPS CONTINUING A RISK FOR SVR
WIND/HAIL AND ISOLD TORNADOES FARTHER E INTO ND TNGT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 4 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 26020.


...CORFIDI

Tornado Watches in North Dakota, 2013Tornado Watches in Montana, 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.