Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 291731
SWODY2
SPC AC 291730

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1230 PM CDT MON JUN 29 2015

VALID 301200Z - 011200Z

...THERE IS A MRGL RISK OF SVR TSTMS FROM THE LOWER MS VALLEY
THROUGH THE TN AND OH VALLEYS INTO THE MID ATLANTIC AREA...

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

...SUMMARY...
SCATTERED THUNDERSTORMS...SOME STRONG TO POSSIBLY SEVERE...ARE
EXPECTED FROM THE MID SOUTH TO THE MIDDLE ATLANTIC. OTHER ISOLATED
SEVERE THUNDERSTORMS MAY DEVELOP ACROSS THE NORTHERN HIGH PLAINS.
GUSTY WINDS AND PERHAPS SOME HAIL ARE THE PRIMARY THREATS.

...SYNOPSIS...

THE LARGE SCALE PATTERN WILL REMAIN CHARACTERIZED BY AN UPPER RIDGE
OVER THE WRN U.S. CENTERED OVER THE GREAT BASIN AND A TROUGH OVER
THE ERN STATES. VORT MAX NOW OVER NRN MN WILL MOVE SEWD THROUGH THE
MEAN TROUGH POSITION INTO THE GREAT LAKES AND OH VALLEY TUESDAY.
ANOTHER PROMINENT VORT MAX OVER THE PACIFIC NW COAST WILL MOVE NEWD
AND CREST THE UPPER RIDGE AND SUBSEQUENTLY TURN SEWD BEFORE
CONTINUING THROUGH THE NRN HIGH PLAINS TUESDAY.

...LOWER MS VALLEY THROUGH OH VALLEY...

A SECONDARY FRONTAL SURGE WILL ACCOMPANY THE VORT MAX SEWD THROUGH
THE OH VALLEY...AHEAD OF WHICH MID-UPPER 60S NEAR-SFC DEWPOINTS WILL
EXIST. THE ATMOSPHERE WILL DESTABILIZE AS THE BOUNDARY LAYER
WARMS...BUT MLCAPE SHOULD REMAIN AOB 2000 J/KG DUE TO MODEST /6.5-7
C/KM/ MID-LEVEL LAPSE RATES. SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG THE FRONT AND WITHIN THE WEAKLY CAPPED WARM SECTOR
WHERE GENERALLY WEAK 0-6 KM SHEAR WILL SUPPORT MULTICELL STORMS. THE
STRONGER STORMS MAY PRODUCE ISOLATED STRONG TO DAMAGING WIND GUSTS
AND HAIL. A SLIGHT RISK MIGHT BE INTRODUCED FOR A PORTION OF THIS
AREA IN LATER OUTLOOKS. HOWEVER...TOO MUCH UNCERTAINTY EXISTS
REGARDING WHERE BEST DESTABILIZATION AND BEST CONCENTRATION OF
STORMS WILL OCCUR /ESPECIALLY GIVEN THE MODEST PARAMETER SPACE/ TO
INTRODUCE A HIGHER RISK CATEGORY AT THIS TIME.

...MID ATLANTIC AND A PORTION OF THE NERN STATES...

WARM FRONT WILL ACCOMPANY A LEAD SHORTWAVE TROUGH THROUGH THIS
REGION WITH MODEST CAPE EXPECTED TO DEVELOP IN THE MOISTENING WARM
SECTOR. GREATER SHEAR PROFILES SHOULD REMAIN EAST WARM FRONT WHERE
MUCH WEAKER INSTABILITY WILL RESIDE. NEVERTHELESS...SOME POTENTIAL
EXIST FOR A FEW ORGANIZED STORMS IN VICINITY OF THIS BOUNDARY DURING
THE AFTERNOON.

...NRN HIGH PLAINS...

A NARROW CORRIDOR OF 1 INCH+ PW WILL EXTEND NWWD ACROSS THE PLAINS
INTO ERN MT AHEAD OF THE PROGRESSIVE SHORT-WAVE TROUGH. THIS FEATURE
WILL CREST THE WRN U.S. RIDGE AND MOVE SEWD ACROSS THE NRN HIGH
PLAINS DURING THE AFTERNOON WITH 01/00Z POSITION EXPECTED ACROSS
SERN MT. LARGE-SCALE ASCENT SHOULD ENHANCE THE PROSPECT FOR
CONVECTION ALONG A NARROW RIBBON OF FOCUSED WARM ADVECTION FROM ERN
MT...SEWD INTO THE BLACK HILLS OF SD. LOCALLY SEVERE WIND GUSTS AND
HAIL ARE THE PRIMARY THREATS WITH THIS CONVECTION FROM LATE
AFTERNOON THROUGH EARLY EVENING.

..DIAL.. 06/29/2015



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