Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS01 KWNS 291952
SWODY1
SPC AC 291951

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0251 PM CDT MON JUN 29 2015

VALID 292000Z - 301200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE OH
VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE UPPER MS
VALLEY...

...THERE IS A MRGL RISK OF SVR TSTMS OVER THE A PORTION OF THE OH
VALLEY...

...THERE IS A MRGL RISK OF SVR TSTMS FROM THE SRN ROCKIES INTO THE
SRN PLAINS...TN VALLEY AND OH VALLEY...

...THERE IS A MRGL RISK OF SVR TSTMS OVER THE NRN ROCKIES...

...SUMMARY...
ORGANIZED SEVERE THUNDERSTORMS WILL PERSIST THROUGH EARLY EVENING
OVER PARTS OF THE MIDDLE OHIO VALLEY AND THE UPPER MISSISSIPPI
VALLEY REGIONS. ISOLATED SEVERE THUNDERSTORMS REMAIN POSSIBLE FROM
PARTS OF THE CENTRAL AND SOUTHERN PLAINS TO ARIZONA...AND OVER THE
NORTHERN ROCKIES.

...DISCUSSION...

PRIMARY CHANGE FOR THIS UPDATE HAS BEEN TO EXTEND THE MARGINAL AREA
TO INCLUDE SRN OK AND NRN TX INTO CNTRL AND SRN ARK WHERE MULTICELL
STORMS ARE EXPECTED TO DEVELOP AND POSE A RISK FOR A FEW DAMAGING
WIND GUSTS AND MARGINALLY SEVERE HAIL. REF SWOMCD 1230 FOR MORE
DETAILED INFORMATION.

OTHERWISE...PRIMARY SEVERE THREAT AREAS WILL REMAIN OVER THE MIDDLE
OH VALLEY AND THE UPPER MS VALLEY REGIONS THROUGH EARLY EVENING
WHERE ONLY MINOR ADJUSTMENTS TO THE OUTLOOK HAVE BEEN MADE FOR THIS
UPDATE.

STORMS DEVELOPING OVER THE NRN ROCKIES WILL ALSO POSE A MARGINAL
SEVERE RISK THIS AFTERNOON AND EARLY EVENING. REF SWOMCD 1231 FOR
MORE INFORMATION.

..DIAL.. 06/29/2015

.PREV DISCUSSION... /ISSUED 1129 AM CDT MON JUN 29 2015/

...MN/WI/IA...
SATELLITE LOOPS SHOW A SHORTWAVE TROUGH OVER MB/WESTERN ONT TRACKING
SOUTHWARD TOWARD MN.  SCATTERED THUNDERSTORMS ARE ONGOING THIS
MORNING OVER THE ARROWHEAD OF MN WHERE SOME HAIL AND GUSTY WINDS
HAVE LIKELY OCCURRED.  THIS ACTIVITY WILL SPREAD SOUTHWARD AND
INCREASE IN COVERAGE BY MID AFTERNOON...AS DAYTIME HEATING
DESTABILIZES THE AIR MASS AND LOW CLOUDS CONTINUE TO ERODE.  MOST
MORNING MODEL SOLUTIONS SHOW SCATTERED THUNDERSTORM DEVELOPMENT OVER
CENTRAL/EASTERN MN AND WESTERN WI.  VERTICAL SHEAR WILL BE
SUFFICIENT FOR ORGANIZED MULTICELL OR ISOLATED SUPERCELL STORMS
CAPABLE OF LARGE HAIL AND DAMAGING WINDS.  STORMS MAY MOVE INTO
NORTHERN IA AFTER DARK BEFORE DIMINISHING.

...OH VALLEY...
ANOTHER SHORTWAVE TROUGH IS NOTED OVER IND/OH/KY THIS
MORNING...ROTATING EASTWARD INTO THE UPPER OH VALLEY.  WIDESPREAD
CLOUD COVER NEAR AND NORTH OF THE UPPER SYSTEM WILL GREATLY LIMIT
DESTABILIZATION OVER THIS REGION TODAY.  HOWEVER...THERE APPEARS TO
BE A ZONE WHERE HEATING SHOULD COMMENCE BY EARLY AFTERNOON FROM
PARTS OF KY/WV NORTHWARD INTO FAR SOUTHERN OH.  FORECAST SOUNDINGS
SHOW SUBSTANTIAL VEERING LOW LEVEL WIND FIELDS AND AT LEAST MARGINAL
INSTABILITY IN THIS REGION.  PRESENT INDICATIONS ARE THAT THE
COMBINATION OF LARGE SCALE FORCING AND DIURNAL DESTABILIZATION WILL
LEAD TO SCATTERED THUNDERSTORMS FROM CENTRAL KY INTO SOUTHERN
OH...TRACKING INTO WESTERN WV THIS EVENING.  THE STRONGEST STORMS
MAY POSE A RISK OF HAIL...GUSTY WINDS...AND PERHAPS A BRIEF TORNADO
OR TWO.

...CENTRAL SOUTHERN ROCKIES...
WATER VAPOR IMAGERY HINTS AT A WEAK FEATURE TRACKING SOUTHWARD
ACROSS CO.  THIS MAY TEND TO INCREASE THE COVERAGE AND INTENSITY OF
THUNDERSTORMS LATER TODAY OVER THE MOUNTAINS OF NORTHERN/CENTRAL NM.
 STRONG NORTHERLY UPPER LEVEL WINDS AND A DEEPLY MIXED BOUNDARY
LAYER WILL PROMOTE A FEW STRONG STORMS CAPABLE OF GUSTY WINDS.

...PACIFIC NORTHWEST...
A SHORTWAVE TROUGH OVER WESTERN ORE WILL TRACK NORTHEASTWARD AND
HELP TO INITIATE SCATTERED THUNDERSTORMS THIS AFTERNOON OVER PARTS
OF WA/ORE INTO ID AND WESTERN MT.  STRENGTHENING WINDS ALOFT AND
SUFFICIENT INSTABILITY ATOP INVERTED-V PROFILES MAY RESULT IN A FEW
STRONG STORMS CAPABLE OF GUSTY/DAMAGING WINDS.  PRESENT INDICATIONS
ARE THAT SEVERE THREAT WILL REMAIN RATHER DISORGANIZED.



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