SPC AC 280107
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0807 PM CDT WED JUN 27 2007
VALID 280100Z - 281200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF NRN NEW
ENGLAND...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID
ATLANTIC INTO SRN CT...
...THERE IS A SLGT RISK OF SVR TSTMS OVER SMALL PORTIONS OF CO/NM...
...NORTHEAST...
QLCS CONTINUES TO DEVELOP EWD INTO AN AXIS OF STRONG INSTABILITY
FROM SERN NY AND ERN ACROSS MUCH OF NJ. DESPITE WEAKLY SHEARED
REGIME...SUBTLE MID LEVEL IMPULSE AND ASSOCIATED BAND OF RELATIVELY
STRONGER WLY MID LEVEL FLOW OF 25-30KT...COUPLED WITH DEEPENING COLD
POOLS...SHOULD MAINTAIN THE THREAT FOR DAMAGING WINDS OVER THE NEXT
FEW HOURS. GREATEST WIND DAMAGE POTENTIAL SHOULD ACCOMPANY THE
BOWING LINE SEGMENT MOVING FROM NRN NJ/SERN NY OVER THE NEXT HOUR OR
SO. LESS ORGANIZED BUT INTENSE MULTICELL STORMS WILL ALSO CONTINUE
TO POSE SOME SMALL HAIL AND DAMAGING WIND THREATS ACROSS ERN PA AND
SRN NJ NEXT FEW HOURS.
FARTHER NORTH...ABUNDANT WARM SECTOR INSTABILITY REMAINS IN PLACE
FROM SRN ONTARIO ACROSS QUEBEC...AHEAD OF A STRONGER SHORT WAVE
TROUGH AND ASSOCIATED LOW AND COLD FRONT DEVELOPING ESEWD INTO THESE
AREAS. LOW LEVEL THETAE/INSTABILITY AXIS ALSO EXTENDS ESEWD FROM THE
LOW IN QUEBEC INTO WRN/CNTRL ME...WHERE A WARM/STATIONARY FRONTAL
ZONE IS SITUATED. MOST INTENSE STORMS ATTM APPEAR TO BE SPREADING
INTO PARTS OF THE ST. LAWRENCE VALLEY OF SRN QUEBEC. MODEST TO
STRONG SHEAR AND FORCING ARE FORECAST TO ACCOMPANY THE EWD
TRANSLATION OF THE SHORT WAVE TROUGH OVERNIGHT. GIVEN POCKETS OF
GENERALLY UNPERTURBED AND UNSTABLE AIR REMAINING AHEAD OF THE
ONGOING ACTIVITY...FROM UPSTATE NY EWD ACROSS ME...THE POTENTIAL FOR
A FEW SEVERE STORMS...POSSIBLY IN THE FORM OF A SMALL MCS...WILL
EXIST THROUGH TONIGHT.
...NRN IND TO SRN LWR MI...
SCATTERED INTENSE STORMS PERSIST WITHIN INSTABILITY AXIS AHEAD OF
PRE-FRONTAL TROUGH FROM LWR MI SWWD ACROSS NRN/CNTRL IND. WEAK
HEIGHT FALLS ON THE SRN EDGE OF THE STRONG CANADIAN SHORT WAVE
TROUGH SHOULD PROMOTE COLD FRONTAL PASSAGE ACROSS PARTS OF THE AREA
OVERNIGHT WITH A FEW INTENSE MULTICELLULAR STORMS CONTINUING TO POSE
SOME THREAT OF DAMAGING WINDS AND SEVERE HAIL OVER THE NEXT COUPLE
OF HOURS. WEAKER INSTABILITY EXISTS DOWNSTREAM FROM THE ONGOING
ACTIVITY WHERE ROBUST CONVECTIVE DEVELOPMENT OCCURRED EARLIER. GIVEN
NARROW CORRIDOR OF SEVERE POTENTIAL...AND TIME OF DAY...WILL
MAINTAIN LOW SEVERE PROBABILITIES ACROSS THIS AREA.
...ROCKY MTNS FROM WY TO NM...
WEAK/DIFFLUENT FLOW ALOFT WITHIN MID/UPPER LEVEL RIDGE AXIS...AND
STRONG HEATING ACROSS THE HIGH TERRAIN...HAVE CONTRIBUTED TO
ISOLATED INTENSE STORMS FROM WY TO NM TODAY. SOME OF THIS ACTIVITY
HAS NOW CONGEALED AND DRIFTED TOWARD GREATER MOISTURE/INFLOW FROM
PUEBLO COUNTY IN CO TO COLFAX/UNION COUNTIES IN NM. WHILE LARGE
SCALE FORCING TO SUSTAIN WIDESPREAD DEEP CONVECTION ACROSS THE
REGION REMAINS SUBTLE/WEAK...ONGOING ACTIVITY SHOULD SUPPORT SEVERE
WIND/HAIL THREAT FOR ABOUT ANOTHER HOUR OR TWO.
...NERN TX...
STRONGER CONVECTION HAS DEVELOPED AHEAD OF MCV DRIFTING NNEWD TOWARD
NERN TX THIS EVENING. HEATING AHEAD OF THIS BAND OF ASCENT HAS
BOOSTED INSTABILITY VALUES IN VERY MOIST AIR MASS ACROSS THE
ARKLATEX. WHILE SHEAR AND FORCING ARE EXPECTED TO REMAIN LIMITED
ACROSS MUCH OF THE AREA TONIGHT...LATEST PROFILER AND VWP
OBSERVATIONS SUGGEST THAT A NARROW AXIS OF GREATER LOW LEVEL
SHEAR...0-1KM SRH PERHAPS UP TO 150 M2/S2...MAY EXIST AHEAD OF THE
INCREASING STORMS. GIVEN THESE CONDITIONS...A LOW PROBABILITY
TORNADO THREAT WILL BE MAINTAINED ACROSS THE AREA.
..CARBIN.. 06/28/2007
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
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