SPC AC 071232
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0732 AM CDT MON AUG 07 2006
VALID 071300Z - 081200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NORTHEAST INTO THE
MID ATLANTIC/CENTRAL APPALACHIANS...
...THERE IS A SLGT RISK OF SVR TSTMS OVER PART OF THE CENTRAL/NRN
HIGH PLAINS...
...THERE IS A SLGT RISK OF SVR TSTMS INTO FAR NRN CA AND WRN/CENTRAL
ORE...
...NORTHEAST INTO THE CENTRAL APPALACHIANS/MID ATLANTIC...
STRONG MID LEVEL TROUGH WILL REMAIN IN PLACE OVER ERN CANADA AND THE
NORTHEAST U.S. AS A SERIES OF FASTER MOVING IMPULSES OVERSPREAD THE
REGION. LEADING SYSTEM NOW MOVING EWD ACROSS SRN QUEBEC WILL SHIFT
EWD AND ALLOW DRIER MID LEVEL AIR AND CLEARING SKIES TO SPREAD FROM
WEST TO EAST ACROSS NEW ENGLAND THROUGH THE DAY...AS ANOTHER IMPULSE
DIGS ESEWD ACROSS ONTARIO/WRN QUEBEC. AT THE SURFACE...A COLD FRONT
WHICH NOW TRAILS ACROSS WRN QUEBEC SWWD INTO THE CENTRAL GREAT LAKES
IS EXPECTED TO MOVE ESEWD INTO NRN NEW ENGLAND THE LOWER GREAT LAKES
BY LATE THIS AFTERNOON. INCREASING SSWLY PREFRONTAL SURFACE WINDS
WILL ALLOW MID/UPPER 60F DEW POINT AXIS TO ADVECT NNEWD ACROSS MOST
OF NEW ENGLAND TODAY. RUC FCST SOUNDINGS INDICATE AXIS OF 1000+
J/KG MLCAPE WILL DEVELOP INTO PORTIONS OF ME BY 21Z...IF SKIES CAN
CLEAR AS EXPECTED...WITH MLCAPE APPROACHING 2000 J/KG INTO THE LOWER
HUDSON VALLEY. THEREFORE...THUNDERSTORMS WILL DEVELOP AND QUICKLY
INTENSIFY AHEAD OF APPROACHING COLD FRONT AS LARGE SCALE ASCENT
INCREASES THROUGH THE DAY. SHEAR IS FORECAST TO BE RATHER
STRONG...EFFECTIVE SHEAR AROUND 40 KT...SUGGESTING ACTIVITY WILL BE
QUICK TO ORGANIZE INTO SMALL LINES/BOW ECHOES AND SUPERCELLS.
DAMAGING WINDS ARE EXPECTED TO BECOME LIKELY WITH THE STRONGER/MORE
ORGANIZED STORMS...WITH 0-1 KM SRH AOA 100 M2/S2 AND RELATIVELY LOW
LCLS SUPPORTING ADDITIONAL THREAT OF TORNADOES THIS AFTERNOON AND
EVENING FROM PORTIONS OF THE MID ATLANTIC INTO NEW ENGLAND.
...CENTRAL AND PART OF THE NRN HIGH PLAINS...
WEAK IMPULSE WILL CONTINUE TO LIFT SLOWLY ENEWD ACROSS THE CENTRAL
ROCKIES TODAY AS BOUNDARY LAYER REMAINS QUITE MOIST ACROSS THE HIGH
PLAINS. APPEARS UPPER 50/LOWER 60F SURFACE DEW POINTS WILL SURVIVE
AFTERNOON HEATING/MIXING AND SUPPORT MODERATE INSTABILITY ACROSS
MUCH OF ERN CO INTO ERN WY/WRN SD/NEB PANHANDLE. THOUGH LOWER TO
MID LEVEL WINDS ARE FORECAST TO REMAIN MODEST...AND LIKELY LIMIT
SUSTAINED SEVERE THREAT EWD INTO THE CENTRAL PLAINS...SUFFICIENT
VEERING WILL BE IN PLACE ACROSS THE HIGH PLAINS FOR 20-30 KT
EFFECTIVE SHEAR. THIS SHOULD SUPPORT SOME ORGANIZATION INTO
CLUSTERS AS STORMS INCREASE AND SPREAD EWD THROUGH THE EVENING AHEAD
OF APPROACHING SYSTEM. ISOLATED DAMAGING WINDS AND LARGE HAIL MAY
ACCOMPANY STRONGER CORES.
...NRN CA INTO ORE...
COMBINATION OF ENHANCED ASCENT AHEAD OF COMPACT UPPER LOW...VERY
STEEP MID LEVEL LAPSE RATES AND MODERATE INSTABILITY WILL AGAIN
SUPPORT CLUSTERS OF STRONG TO SEVERE THUNDERSTORMS FROM FAR NRN CA
INTO WRN/CENTRAL ORE. FORECAST SOUNDINGS APPEAR FAVORABLE FOR LARGE
HAIL WITH H5 TEMPS AOB -12C AND ISOLATED DAMAGING WINDS WITH THIS
ACTIVITY.
..EVANS/GUYER.. 08/07/2006
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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