Severe Storm Outlook Narrative (AC)
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
465
ACUS02 KWNS 291733
SWODY2
SPC AC 291732

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1232 PM CDT SUN MAY 29 2016

VALID 301200Z - 311200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE NRN AND
CNTRL PLAINS...

...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SRN HIGH PLAINS...

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

...THERE IS A MRGL RISK OF SVR TSTMS OVER A PORTION OF NEW
ENGLAND...

...SUMMARY...
ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PARTS OF THE
NORTHERN GREAT PLAINS SOUTHWARD INTO THE CENTRAL AND SOUTHERN HIGH
PLAINS MONDAY AFTERNOON AND EVENING.  ISOLATED STRONG TO PERHAPS
LOCALLY SEVERE STORMS MAY DEVELOP OVER PORTIONS OF NEW ENGLAND
DURING THE AFTERNOON. LOCALLY DAMAGING WIND GUSTS AND LARGE HAIL
WILL BE THE MAIN THREATS.

...SYNOPSIS...

COMPLEX SPLIT FLOW REGIME WILL PERSIST MONDAY. IN THE NRN STREAM A
SHORTWAVE TROUGH NOW OVER THE PACIFIC NW IS FORECAST TO AMPLIFY AS
IT MOVES INTO THE NRN HIGH PLAINS DURING THE AFTERNOON. THE NEGATIVE
TILT TROUGH CURRENTLY OVER THE GREAT LAKES WILL DEAMPLIFY AS IT
CRESTS UPPER RIDGE OVER THE NERN STATES. IN THE SRN STREAM THE
CUTOFF UPPER LOW OVER THE SWRN U.S. WILL DRIFT VERY SLOWLY EWD
ACROSS AZ...BUT POTENTIAL EXISTS FOR WEAKER DOWNSTREAM IMPULSES TO
MOVE INTO THE SRN PLAINS.

A SFC LOW WILL EVOLVE OVER THE NRN HIGH PLAINS IN ASSOCIATION WITH
THE APPROACHING SHORTWAVE TROUGH. BY MID-DAY A WARM FRONT WILL
EXTEND FROM THE LOW OVER WRN SD EWD INTO THE UPPER MS VALLEY. A COLD
FRONT WILL ADVANCE SEWD THROUGH ERN MT AND EVENTUALLY MERGE WITH THE
SFC TROUGH OVER THE NRN HIGH PLAINS.  THE COLD FRONT WILL ACCOMPANY
THE PROGRESSIVE NRN-STREAM SHORTWAVE TROUGH THROUGH THE DAKOTAS AND
NEB MONDAY EVENING AND OVERNIGHT. FARTHER SOUTH THE DRYLINE WILL
PERSIST OVER THE SRN AND CNTRL HIGH PLAINS.

...NRN AND CNTRL PLAINS AREA...

SLY LOW-LEVEL WINDS WILL INCREASE AS LEE TROUGH BECOMES ESTABLISHED
ACROSS THE HIGH PLAINS TONIGHT INTO MONDAY. MODIFIED CP AIR WITH MID
50S TO LOW 60S F DEWPOINTS WILL ADVECT NWD THROUGH THE PLAINS
BENEATH PLUME OF STEEPER /7.5-8 C/KM/ LAPSE RATES CONTRIBUTING TO
MODERATE INSTABILITY /1500-2000 J /KG MLCAPE/ AS THE SFC-LAYER
WARMS. STORMS WILL LIKELY DEVELOP WITHIN ZONE OF INCREASING
DEEP-LAYER ASCENT ALONG THE SEWD-ADVANCING COLD FRONT AND
PRE-FRONTAL TROUGH. DEEP VERTICAL SHEAR WILL UNDERGO ONLY A MODEST
INCREASE /30-35 KT/ WITH MULTICELLS THE PREDOMINANT STORM MODE.
ISOLATED DAMAGING WIND AND LARGE HAIL WILL BE THE MAIN THREATS.

...SRN HIGH PLAINS...

OVERALL PATTERN WILL REMAIN SIMILAR TO TODAY. IN WAKE OF ANY
RESIDUAL EARLY STORMS THE ATMOSPHERE IS EXPECTED TO DESTABILIZE EAST
DRYLINE ACROSS WRN TX. REMNANT EML PLUME WILL RESIDE ABOVE DEWPOINTS
GENERALLY IN THE MID-UPPER 60S OVER SWRN TX WITH UPPER 50S TO LOW
60S F FARTHER NORTH. MODEST MID-LEVEL WINDS WILL PERSIST DOWNSTREAM
FROM THE SWRN U.S. UPPER LOW ALONG WITH WEAK IMPULSES EMBEDDED IN
SRN STREAM. AT LEAST WIDELY SCATTERED STORMS WILL LIKELY ONCE AGAIN
DEVELOP OVER THE HIGHER TERRAIN AS WELL AS ALONG DRYLINE AND SPREAD
EWD THROUGH WRN TX. VERTICAL SHEAR FROM 30-40 KT WILL SUPPORT BOTH
MULTICELL AND SOME SUPERCELL STRUCTURES WITH LOCALLY DAMAGING WIND
GUSTS AND LARGE HAIL THE MAIN THREATS THROUGH MID EVENING.

...NEW ENGLAND...

WIDESPREAD CLOUDS/PRECIP ASSOCIATED WITH THE REMNANTS OF TROPICAL
STORM BONNIE WILL SHEAR NEWD ALONG THE MID-ATLANTIC AND NEW ENGLAND
COASTS DURING THE DAY.  IT APPEARS THERE MAY BE A SMALL WINDOW OF
OPPORTUNITY FOR ISOLD STORM DEVELOPMENT TO OCCUR WHERE STRONGER
HEATING OCCURS FARTHER NW FROM NEAR THE ADIRONDACKS INTO NRN NEW
ENGLAND AMIDST AN ADEQUATELY MOIST AIRMASS /SURFACE DEWPOINTS IN THE
LOWER 60S/.  YET...FORECAST SOUNDINGS ACROSS THIS REGION ONLY SHOW
MARGINAL BUOYANCY DEVELOPING BY PEAK HEATING DESPITE MODERATELY
STRONG WIND PROFILES.  AS SUCH...A COUPLE OF STRONGER STORMS MAY
DEVELOP DURING THE AFTERNOON AND POSE PRIMARILY A LOW-PROBABILITY
WIND DAMAGE RISK BEFORE STORMS MOVE E OF THE INSTABILITY AXIS AND
DIURNAL STABILIZATION OCCURS BY EARLY EVENING.

..DIAL.. 05/29/2016

$$



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.