SPC AC 260554
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1254 AM CDT MON JUL 26 2010
VALID 261200Z - 271200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF ND/NORTHERN
MN...
...SYNOPSIS...
THE PRIMARY BELT OF WESTERLIES WILL REMAIN OVER CANADA AND THE
ADJACENT NORTHERN TIER OF THE CONUS TODAY...WITH A SOMEWHAT WEAKER
JET STREAM ALOFT EXISTING DOWNSTREAM FROM AN EASTERN PACIFIC TROUGH
TO THE GREAT BASIN/NORTHERN HIGH PLAINS. A POTENT/POSITIVE TILT
SHORTWAVE TROUGH WILL DIG SOUTHEASTWARD OVER ALBERTA/SASKATCHEWAN
THROUGH TONIGHT...WHILE A SURFACE LOW GRADUALLY DEEPENS IN VICINITY
OF A NORTHERN HIGH PLAINS SURFACE TROUGH AND COLD FRONT MOVING
INTO/ACROSS MT/ND.
...NORTHERN PLAINS...
ON THE NOSE OF A VEERING LOW LEVEL JET...EARLY DAY STORMS
POTENTIALLY CAPABLE OF HAIL MAY BE ONGOING ACROSS PORTIONS OF
ND/NORTHWEST MN AT THE BEGINNING OF THE PERIOD...WITH THIS ACTIVITY
EXPECTED TO GRADUALLY SPREAD EASTWARD ACROSS NORTHERN MN AND WANE IN
INTENSITY THROUGH THE LATE MORNING HOURS. IN THE WAKE OF THESE
STORMS...SLIGHT UPPER RIDGING/WARM TEMPERATURES ACROSS THE WARM
SECTOR SHOULD LARGELY CAP TSTM DEVELOPMENT FOR MUCH OF THE
AFTERNOON. BY LATE AFTERNOON/NEAR-SUNSET...ISOLATED TO SCATTERED
TSTMS SHOULD DEVELOP WITHIN A NORTHEAST-SOUTHWEST CORRIDOR ACROSS
THE WESTERN DAKOTAS AND NORTHEAST WY/SOUTHEAST MT IN VICINITY OF A
SURFACE TROUGH/TRIPLE POINT. THE STRONGEST OF THESE STORMS WILL
LIKELY POSE A RISK FOR LARGE HAIL/DAMAGING WINDS...AS STEEPENING MID
LEVEL LAPSE RATES/STRENGTHENING TROPOSPHERIC WINDS WILL BE CONDUCIVE
FOR SOME SUPERCELLS AND MULTICELL LINE SEGMENTS. EITHER VIA THE
EVENING REMNANTS OF THESE STORMS AND/OR PERHAPS MORE LIKELY...STORM
CLUSTERS PROPAGATING OUT OF SOUTHERN SASKATCHEWAN/MANITOBA...IT
SEEMS PROBABLE THAT STORMS MAY GROW UPSCALE TONIGHT AND SPREAD
EAST-SOUTHEASTWARD INTO/ACROSS EASTERN ND/NORTHERN MN. AS
SUCH...DAMAGING WINDS MAY VERY WELL BECOME AN INCREASING CONCERN
THROUGH THE EVENING/OVERNIGHT WITH POTENTIAL FOR A QUASI-LINEAR
FORWARD PROPAGATING MCS.
...NORTHERN CA/SOUTHERN ORE/WESTERN NV...
UPPER TROUGH OFF THE WEST COAST WILL CONTINUE TO SLOWLY MIGRATE
EASTWARD THROUGH THE PERIOD...WITH HEIGHT FALLS AS FAR EAST AS THE
GREAT BASIN. THIS SCENARIO WILL MAINTAIN A BELT OF ENHANCED
FLOW/RELATIVELY COOL TEMPERATURES ALOFT OVER THE REGION. WITH
INCREASING PWAT VALUES/DAYTIME HEATING...ANOTHER ROUND OF
STRONG/POTENTIALLY SEVERE AFTERNOON/EVENING STORMS ARE LIKELY TO
DEVELOP OFF/NORTHEAST OF THE SIERRA CREST...WITH SUSTAINED
STORMS/MULTICELLS EXPANDING ACROSS NORTHWEST NV/SOUTH ORE WITH TIME.
ISOLATED SEVERE HAIL AND/OR A FEW DAMAGING WIND GUSTS WILL BE
POSSIBLE.
...CAROLINAS AND SOUTHEAST/GULF COAST STATES...
AN INCREASE IN TSTM COVERAGE/VIGOR SHOULD OCCUR DURING THE AFTERNOON
ESPECIALLY AMID POCKETS OF STRONGER HEATING ALONG/SOUTH OF A SLOW
MOVING/ROUGHLY WEST-EAST ELONGATED FRONTAL ZONE ACROSS THE REGION.
DOWNBURSTS CAPABLE OF WIND DAMAGE WILL THE PRIMARY HAZARD ON AN
ISOLATED BASIS.
..GUYER/JEWELL.. 07/26/2010
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
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