Severe Thunderstorm Warning 20, NWS Baltimore/Washington

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON
917 PM EDT SAT MAY 6 2000

H5 RDG IS WKNG AND FLATTENING OUT THIS EVE AS SHRTWV ENERGY MOVES
THROUGH NEW ENG AND ANOTHER SHRTWV MVS INTO KY/IN. THIS KY/IN SHRTWV WL
HEAD EWD...WEAKEN AND SHEAR OUT OVR THE RGN MON. H5 RDG WL BUILD OVR
THE AREA AGAIN TUE AHEAD OF THE NXT SHRTWV MOVING INTO THE WRN OH VLY.

DESPITE THE LACK OF A SYNOPTIC TRIGGER...ENUF INSTABILITY DVLPD THIS
AFTRN TO TRIGGER ISOLD CNVCTN IN THE MTNS AND SW COUNTIES. A FEW CELLS
ARE HOLDING ON OVR THE HIGHLANDS BUT EXPECT THEM TO DIE NXT FEW HRS AS
WE LOOSE THE INSTABILITY. WL TAKE A LAST LOOK AT THE 88D BFR ISSUING
ZNS TO SEE IF WE NEED TO KEEP A LOW POP IN THAT AREA FOR A FEW MORE
HRS. 01Z DWPTS INDICATE MIN TEMPS ARE IN LINE SO NO ADJUSTMENT NEEDED
THERE. WL CHG FAR WRN AREAS TO P/C AS SATELLITE IMAGERY SHOWS HI CLDS
ADVANCING TOWARD THAT AREA AHEAD OF THE KY/IN SHRTWV.

WE HAVE HAD ISOLD CNVCTN THE PAST 2 DAYS WITH NO EVIDENT SYNOPTIC SCALE
TRIGGER. ON MON...CONDS APPEAR TO BE MORE FAVORABLE FOR CNVCTN.  WKNG
SHRTWV WL MOVE INTO THE AREA DURING THE AFTRN. 18Z ETA SHOWS LIS ARE
NEGATIVE AND CAPES REACH 500 TO 1000. IN ADDTN...PCP WATER IS OVR
1.25"...TTS AROUND AROUND 50 AND KINDEX AROUND 30. I HATE TO ADD THE
POP FOR THE 2ND PD ON THIS SHIFT BUT MDLS ARE TOO COMPELLING. IN
ADDTN...ALL SURROUNDING OFFICES ADJOINING OUR ZNS HAVE A POP IN FOR
MON. WE WL GO AHEAD AND ADD A 30 POP FOR TSRA FOR ALL AREAS MON EXCEPT
RIGHT ALG THE BAY WHERE ANY SCT/ISOLD CNVCTN WOULD HOLD OFF TIL 3RD PD.
MID SHIFT CAN EXPAND THE POP EWD FOR MON EVE IF 00Z GUIDANCE COMPELLS
THEM TO DO SO.

850MB TEMPS COOL A COUPLE OF DEG ON MON WHICH WHEN COMBINED WITH CLDNS
FROM WKNG SHRTWV MAY HOLD TEMPS DOWN A DEG OR TWO FROM TDAS NUMBERS.
RIGHT NOW WL NOT TINKER WITH THE MAX TEMPS AND WL PASS ALG OUR THOUGHTS
TO THE MID SHIFT.

NO 3RD OR 4TH PD CHGS.

.LWX...NONE.