Flash Flood Warning 58, NWS State College, PA

CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
215 AM EST SUN NOV 9 1997

CURRENT RADAR LOOP SHOWS LIGHT RAIN/SHOWERS/DRIZZLE OVER MUCH OF
THE CTP CWA ATTM.  PCPN IS STARTING TO FILL-IN IN INTENSITY AND
COVERAGE ONCE AGAIN...ALTHOUGH NOTHING HEAVY ATTM.  THIS PCPN IS
ALL MOVING NEARLY SOUTH AS IT ROTATES AROUND THE MID AND UPPER
LEVEL LOW PRESSURE SYSTEMS.  LOW PRESSURE IS OFF THE JERSEY
COAST...WITH SURFACE TROF EXTENDING NW INTO PA.  WE MAY BE SEEING
SOME ENHANCEMENT OVER PA ATTM WITH THE ADDED CONVERGENCE OF THE
NRLY FLOW INTO THE CONVERGENCE ZONE ASSOCIATED WITH SURFACE TROF
RUNNING E-W ACROSS CENTRAL PORTIONS OF THE STATE.

BOTH ETA AND NGM ARE VERY SIMILAR HANDLING THE MOVEMENT OF THE
SURFACE AND UPPER LEVEL SYSTEMS TODAY.  EARLY ETA MODEL PANELS
(VALID 06Z) SEEMS TO HAVE CAPTURED THE CURRENT PCPN FIELDS MUCH
BETTER THAN THE NGM...SO WILL LEAN MUCH MORE HEAVILY ON THIS MODEL
FOR QPF AND THE LIKE.

UPPER LEVEL LOW...AND REFLECTION TO THE SURFACE LOW...WILL FINALLY
START TO MAKE SOME PROGRESS NORTH AND EAST TODAY AS THE NEXT POTENT
UPPER LEVEL KICKER COMES IN TO CLEAN THINGS OUT.  WEAK RIDGING
ALOFT IS PROGGED ACROSS THE REGION BETWEEN 18 AND 24 HOURS FROM
NOW.

WITH THE LOW PRESSURE LIFTING TO THE NORTH...NORTHERLY LOW AND MID
LEVEL FLOW WILL DEVELOP THIS MORNING AND CONTINUE INTO THE
AFTERNOON.  WHILE THIS IS NORMALLY A GOOD DRYING FLOW FOR PA...THIS
PATTERN WILL ACTUALLY HELP TO PULL IN SOME ADDITIONAL MOISTURE INTO
THE STATE THROUGH MID AFTERNOON ON THE BACK SIDE OF THE SYSTEM.
NOT UNTIL THE WHOLE SYSTEM ACTUALLY MOVES EAST LATER IN THE DAY
DOES DRY AIR FINALLY MOVE INTO THE REGION...FROM WEST TO EAST.

MODEL SOUNDINGS AND CROSS SECTIONS WOULD SUGGEST DEEP LOW LEVEL
MOISTURE LINGERING IN AOO AND UNV TIL 18/19Z AND TIL AROUND 22Z IN
IPT.  THINGS SHOULD CLEAR NICELY TONIGHT BEFORE HIGH CLOUDS START
STREAMING IN FROM THE WEST EARLY MONDAY MORNING.

...SUGGESTIONS...

CURRENT ZONES LOOK PRETTY MUCH ON TRACK.  WOULD HOWEVER NOT BE AS
OPTIMISTIC WITH CLEARING ESPECIALLY IN THE WESTERN (PIT) ZONES.
SUGGEST KEEPING SPOTTY LIGHT RAIN/DRIZZLE FOR THE MORNING...WITH A
FEW BREAKS OF LATE DAY SUN.  FEEL ONLY NRN MTS WILL TRULY BECOME
"PARTLY CLOUDY" LATER TODAY.  FOR PHI...IPT WILL REMAIN CLOUDY ALL
DAY AND WILL PROBABLY HAVE TO EXTEND THE MENTION OF LIGHT
RAIN/DRIZZLE INTO THE MID AFTERNOON.  PCPN WILL END IN MDT A BIT
SOONER THAN IPT...AND NW FLOW AND `DOWNSLOPING MAY ALSO BRING SOME
BREAKS OF LATE DAY SUN.

JUNG