Severe Thunderstorm Warning 220, NWS Baltimore/Washington

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON
300 PM EDT MON AUG 7 2000

KLWX RADAR SHOWING WIDELY SCATTERED THUNDERSTORMS DEVELOPING OVER THE
WV PANHANDLE AND ACROSS NORTHERN MD.  AMS AT TIME IS RATHER UNSTABLE
WITH 18Z LAPS INDICATING CAPE VALUES BETWEEN 3000 AND 4000 J/KG.  NO
FOCUS MECHANISM SHOWING UP ON CB-LAPS PLOT... BUT TROF ALONG THE
LEESSIDE OF APPALACHIANS MAY BE WHAT'S CAUSING THE DEVELOPING OVER OUR
NRN CWA.  EXPECTING SCATTERED SHOWERS AND STORMS TO CONTINUE INTO THE
EVENING HOURS... MAINLY ALONG AND TO THE EAST OF THE BLUE RIDGE. DEGREE
OF INSTABILITY WOULD SUGGEST THAT ISOLATED SEVERE STORMS ARE POSSIBLE..
AND WILL HAVE TO MONITOR.

FFA IN EFFECT THROUGH 800 PM FOR THE NW 1/4 OF CWA. AT TIME... AREAL
COVERAGE OF PRECIP SUGGESTS THAT OVERALL FLOODING THREAT IS MINIMAL. AT
TIME.. PLAN TO CANCEL FFA WITH AFTERNOON ZONE ISSUANCE... BUT WILL BASE
FINAL DECISION ON RADAR AND SATELLITE IMAGES OVER THE NEXT HOUR.

NO REAL WEATHER MAKER ACROSS OUR AREA FOR THE NEXT 36 HOURS. W/SW FLOW
SFC AND ALOFT WILL KEEP A VERY WARM AMS OVER THE AREA.. BUT BOTH
ETA/NGM HINTING AT WINDS TURNING A BIT MORE WESTERLY TOMORROW RESULTING
IN DEW POINTS DROPPING BACK 4 OR 5 DEGREES.  FORECAST HEAT INDEX VALUES
WILL BE AROUND 100..DEPENDING ON HOW FAR DEW POINTS DROP. WILL ISSUE
SPS WITH AFTERNOON PACKAGE HIGHLIGHTING WARM TEMPS ON TAP FOR TUESDAY.

MODEL SOUNDINGS INDICATE WARMER LOW LEVEL TEMPS ACROSS THE AREA
TOMORROW.. AND SUGGEST THAT WE MAY END UP BEING CAPPED. WILL TAKE OUT
MENTION OF PRECIP FOR TOMORROW AFTERNOON FOR THAT REASON. SHORT WAVE
MOVING THROUGH THE AREA TUESDAY NIGHT ALONG WITH A WEAK SURFACE
REFLECTION.. SO WILL KEEP CHANCE POPS IN THE AREA FOR PERIODS 3 AND 4.

FWC/FAN TEMPS HAVE BEEN RUNNING A BIT HIGH THE PAST FEW RUNS... AND
TODAY SEEMS TO BE A CONTINUATION OF THIS TREND. DEFINITELY A WARM DAY
ON TAP.. BUT PREFER 90 TgO 95 OVER MID 90S.

.LWX...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.

MARGRAF!