Severe Storm Outlook Narrative (AC)
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000
ACUS02 KWNS 271713
SWODY2
SPC AC 271712

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1212 PM CDT WED MAY 27 2015

VALID 281200Z - 291200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN AND
CNTRL HIGH PLAINS...

...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PARTS OF THE GREAT
PLAINS...OZARKS AND LOWER MS VALLEY...

...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PARTS OF NEW ENGLAND...

...SUMMARY...
SCATTERED SEVERE THUNDERSTORMS WITH LARGE HAIL AND WIND DAMAGE MAY
DEVELOP ACROSS PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS ON
THURSDAY. OTHER THUNDERSTORMS MAY DEVELOP ACROSS PARTS OF NEW
ENGLAND THURSDAY AFTERNOON WHERE STRONG WIND GUSTS WILL BE POSSIBLE.
MARGINALLY SEVERE THUNDERSTORMS MAY ALSO DEVELOP IN THE NORTHERN
PLAINS AND ACROSS THE SOUTHERN PLAINS EASTWARD INTO THE ARKLATEX AND
LOWER MISSISSIPPI VALLEY THURSDAY AFTERNOON.

...GREAT PLAINS...
AN UPPER-LEVEL TROUGH WILL MOVE ACROSS THE FOUR CORNERS REGION ON
THURSDAY AS WEST TO SOUTHWEST MID-LEVEL FLOW REMAINS OVER THE GREAT
PLAINS. AT THE SFC...A DRYLINE SHOULD BE LOCATED FROM ERN CO SWD
ACROSS ERN NM WITH SOUTH SOUTHEASTERLY FLOW IN PLACE ACROSS THE SRN
AND CNTRL PLAINS. SFC DEWPOINTS ARE FORECAST TO BE IN THE MID 60S TO
THE LOWER 70S F TO THE EAST OF THE DRYLINE WHICH SHOULD RESULT IN
THE DEVELOPMENT OF AN AXIS OF MODERATE TO STRONG INSTABILITY BY
MIDDAY FROM WEST TX NWD INTO WRN KS. MODEL FORECASTS ARE IN
REASONABLY GOOD AGREEMENT GENERATING SCATTERED THUNDERSTORMS ACROSS
THE SRN AND CNTRL HIGH PLAINS DURING THE AFTERNOON. STRONG TO SEVERE
THUNDERSTORMS APPEAR LIKELY TO ORGANIZE ON THURSDAY WITH SEVERAL
CONVECTIVE CLUSTERS MOVING EWD ACROSS THE SLIGHT RISK AREA.

NAM FORECAST SOUNDINGS AT 00Z/FRI ALONG THE INSTABILITY AXIS FOR
DODGE CITY...AMARILLO AND LUBBOCK SHOW IMPRESSIVE THERMODYNAMICS
WITH MLCAPE OF 3000 TO 3500 J/KG AND 850 TO 500 MB LAPSE RATES NEAR
8.0 C/KM. THE WIND PROFILES SHOW DIRECTIONAL SHEAR IN THE LOW TO
MID-LEVELS WITH 0-6 KM SHEAR OF 30 TO 35 KT. THIS SHOULD BE ENOUGH
FOR ORGANIZED MULTICELLS AND POSSIBLY SUPERCELLS WHERE STORMS HAVE
ACCESS TO THE STRONGEST INSTABILITY. SUPERCELLS SHOULD HAVE A
POTENTIAL FOR ISOLATED LARGE HAIL WHILE WIND DAMAGE MAY BE MOST
COMMON WITH THE MORE INTENSE MULTICELL LINE SEGMENTS.

...NEW ENGLAND...
AN UPPER-LEVEL TROUGH AND AN ASSOCIATED COLD FRONT IS FORECAST TO
MOVE INTO NEW ENGLAND ON THURSDAY. AHEAD OF THE FRONT...A NARROW
CORRIDOR OF LOW-LEVEL MOISTURE SHOULD BE IN PLACE FROM SRN NEW
ENGLAND NEWD INTO MAINE WHERE SFC DEWPOINTS ARE FORECAST TO BE IN
THE MID TO UPPER 60S F. THIS SHOULD ALLOW FOR THE DEVELOPMENT OF
MODERATE INSTABILITY BY AFTERNOON WITH THUNDERSTORMS INITIATING
ALONG THE INSTABILITY AXIS. SEVERAL LINE SEGMENTS MAY DEVELOP ALONG
AND AHEAD OF THE FRONT...MOVING EWD ACROSS THE MARGINAL RISK AREA
DURING THE DAY. FORECAST SOUNDINGS AT 21Z FROM MASSACHUSETTS NEWD
INTO MAINE SHOW MLCAPE OF 1500 TO 2000 J/KG WITH STEEP LAPSE RATES
FROM THE SFC TO 700 MB. THIS COMBINED WITH 30 TO 40 KT OF 0-6 KM
SHEAR SHOULD SUPPORT A MARGINAL WIND DAMAGE THREAT DURING THE
AFTERNOON.

..BROYLES.. 05/27/2015



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