National Weather Service Raw Text Product

227 
ACUS1 KMKC 020601
SWODY1
MKC AC 020554

CONVECTIVE OUTLOOK...REF AFOS NMCGPH94O.

VALID 021200Z - 031200Z

THERE IS A MDT RISK OF SVR TSTMS OVER VA..PA..MD..NJ..DE..WV..AND
PARTS OF NY..NC..KY..OH...TO THE RIGHT OF A LINE FROM 15 S EWN GSO
5I3 30 ESE LUK CMH YNG 30 SE ROC 45 WSW ALB NEL.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM
15 ESE SAV 55 E RMG 30 SW MKL PAH MIE MTC ...CONT... 15 N EFK EEN
ACK.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 NNE SSI GAD MEM
P02 10 NW BMI 20 E AUW MQT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 WNW OFK 30 S EAR
CYS 30 NNE RKS ENV TPH 30 NE FAT 45 NW SAC 25 SE MFR 25 SE YKM
40 ENE GEG 40 SW CTB LWT 4BQ 35 SE RAP 40 WNW OFK.

...SYNOPSIS...
UPPER LOW WILL REMAIN ANCHORED OVER ERN CANADA TODAY...ALLOWING A
SERIES OF SHORTWAVE TROUGHS TO MOVE QUICKLY EWD ACROSS THE NRN U.S.
IMPRESSIVE UPPER RIDGE WILL ALSO REMAIN OVER THE GULF COAST AND
WILL MAINTAIN SEASONABLY-STRONG W-NWLY FLOW ALOFT OVER THE ERN
STATES.  OUT WEST...STRONG SHORTWAVE TROUGH WILL DIG SWD INTO THE
NRN ROCKIES WHILE UPPER LOW HOLDS OFF THE CA COAST.

...SEVERE THUNDERSTORM FORECAST DISCUSSION...
NORTHWEST FLOW SEVERE EVENT APPEARS LIKELY INTO MUCH OF THE UPPER
OHIO VALLEY AND MID ATLANTIC THIS AFTERNOON AND EVENING.  THOUGH
SOME CONCERN REMAINS REGARDING AVAILABLE MOISTURE/INSTABILITY...
STRONG S-SWLY LOW LEVEL FLOW AHEAD OF FAST MOVING COLD FRONT DURING
THE DAY...SHOULD ALLOW SUFFICIENT MOISTURE TO RETURN BY LATE IN THE
DAY.  IT APPEARS REASONABLE FOR LOWER TO MID 50F DEW POINTS TO
ADVECT INTO CNTRL NY DURING THE DAY ...WHILE 60+F DEW POINTS ADVECT
INTO THE DELMARVA REGION.  POOL OF MID 60/LOW 70 SURFACE DEW POINTS
UNDER STRONG CAP OVER THE MID MS VALLEY REGION WILL LIKEWISE ADVECT
QUICKLY NEWD INTO THE OHIO VALLEY BY EARLY IN THE DAY.  THIS WILL
SUPPORT A VERY UNSTABLE AIR MASS INTO PARTS OF OH/NRN KY/WRN WV BY
18Z WITH FORECAST CAPES OVER 3000 J/KG.
THE FAST MOVING COLD FRONT WILL BE ADVANCING INTO THE UPPER OHIO
VALLEY AND SHOULD ALLOW SEVERE STORMS TO RAPIDLY DEVELOP THROUGH
THE AFTERNOON INTO THE CNTRL APPALACHIANS.  FRONT SHOULD EXTEND
ALONG THE RIM OF THE APPALACHIANS BY THE EARLY EVENING...AND WILL
PUSH QUICKLY OFF THE MID ATLANTIC COAST OVERNIGHT.  FURTHER
DEVELOPMENT WILL OCCUR BOTH ALONG FRONT AND OVER THE HIGHER TERRAIN
BY LATE IN THE DAY...WHICH WILL SPREAD RAPIDLY EWD.  FORECAST
SOUNDINGS YIELD CAPES FROM 1500-2500 J/KG INTO THE DELMARVA REGION
BY 00Z...WITH 500-1000 J/KG CAPES EXTENDING INTO CENTRAL NY.

VERY STRONG /50-70 KT AT H5/ NW FLOW WILL EXTEND ACROSS ALL THE
EAST COAST DURING THE DAY...AND WILL OVERRIDE 30-40 KT SWLY H85
WINDS.  THIS WILL SUPPORT THREAT OF ORGANIZED SEVERE THUNDERSTORMS
OVER A LARGE PART OF THE EASTERN STATES...CONTINUING THROUGH THE
EVENING INTO THE MID ATLANTIC/WRN NEW ENGLAND.  STORM-RELATIVE
HELICITIES AND WINDS INDICATE SUPERCELLS AND ISOLATED TORNADOES
WILL BE POSSIBLE.  HOWEVER LINE OF STORMS MAY FORM ALONG FRONT
AND...GIVEN ORIENTATION OF LINE PERPENDICULAR TO THE VERY STRONG
MID/UPPER LEVEL WINDS...WIND DAMAGE SHOULD BE PREVALENT WITH
NUMEROUS BOW ECHOES.

..EVANS.. 06/02/98