Flash Flood Warning 41, NWS State College, PA

CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
915 PM EST FRI MAR 20 1998

...WORK ZONES SENT TO PHL/PIT VIA ADMCTP AT 900 PM...

...DISCUSSION...

SAT LOOPS SHOW UPPER LOW SPINNING EAST ACROSS KY. SFC LOW IS
BEGINNING TO DEVELOP OVER NC. COLD AIR IS OOZING SOUTH FROM NY
STATE...WITH ELM REPORTING ZR-. ALL THE INGREDIENTS ARE COMING
TOGETHER FOR A MAJOR STORM ACROSS CENTRAL PA THROUGH SATURDAY NIGHT.

ALL MODELS...NGM/ETA/MESO-ETA/AVN SHOW BASICALLY THE SAME TRACK WITH
THE SFC AND UPR LOWS TONIGHT THROUGH SATURDAY NIGHT...TAKING THE
UPPER LOW ACROSS MD TO NJ BY SATURDAY NIGHT...WITH THE SFC LOW
TRACKING TO CHESAPEKE BAY BY SATURDAY EVE. THE NGM IS THE WARMEST IN
THE LOW-LVLS...BUT DOES NOT SEEM TO BE RESOLVING THE SHALLOW COLD
AIR ALREADY PRESENT IN NY STATE. THE ETA AND ESPECIALLY THE MESO-ETA
ARE COLDER...BUT EVEN THEY DO NOT SEEM COLD ENOUGH OVER NY STATE...
WHICH WILL BE OUR SOURCE OF COLD AIR WITH THIS EVENT.

FIRST...THE FLOODING. RADAR LOOPS SHOW MODERATE TO HEAVY RAIN
TRAINING NORTH TOWARD S CNTRL PA. OBVIOUSLY THE FLOOD WATCH WILL
REMAIN ACROSS THE SOUTH AND WE MAY HAVE TO START ISSUING WARNINGS IF
THE TRAINING DOES NOT END. THE TRAINING ECHOES LINE UP WELL WITH THE
UPPER FLOW FROM THE SOUTH...SO TRAINING IS LIKELY TO CONTINUE. LDS
SHOWS LIGHTNING STRIKES UP TO THE PA BORDER ACRS THE LOWER
SUSQ...THE AFTERNOON FORECAST SEEMS TO HAVE HAD A GREAT HANDLE ON
THAT AND WILL LEAVE MENTION OF THUNDER GOING FOR THE SOUTH.

WITH FREEZING RAIN ALREADY AT ELM AND COLD AIR SLOWLY TRACKING SOUTH
MIXED FREEZING PRECIP WILL BE STARTING SOON ACROSS THE NORTHERN
COUNTIES. THEREFORE WILL GO WITH A WARNING FOR THE NORTHERN TIER OF
COUNTIES AS BAD WX WILL BE STARTING IN THE FIRST PD. ETA/MESO ETA
MODEL SOUNDINGS ARE TOO WARM IN THE BOUNDARY LYR ACROSS SRN NY
ATTM...BUT EVEN THOSE MODELS WOULD CHANGE PRECIP TO ALL SNOW AROUND
12Z ACROSS THE NORTHERN COUNTIES...WITH SNOW AMOUNTS OF 6 TO 12
INCHES SATURDAY THROUGH SATURDAY NIGHT. AMOUNTS COULD ACTUALLY BE
GREATER THAN THAT AS SNOW IS PROGGED TO LINGER THROUGH ALL OF
SATURDAY NIGHT.

FARTHER SOUTH WILL EXTEND THE WINTER STORM WATCH FOR SATURDAY TO THE
LAURELS AND TO BLAIR AND BEDFORD COUNTIES...AS MESO-ETA SOUNDINGS
INDICATE A CHANGE-OVER BY EARLY AFTERNOON...AND AGAIN THE MESO-ETA
IS CURRENTLY RUNNING TOO WARM ACROSS SOUTHERN NY. ALSO WILL EXTEND
THE WATCH THROUGH SATURDAY NIGHT AS WORST CONDITIONS MAY BE THEN AS
SNOW BEGINS TO WIND DOWN BUT COLDER BNDRY TEMPS WILL ALLOW FOR GOOD
ACCUMULATIONS EVEN ON ROADS. WILL KEEP FORECASTS OF LIGHTER SNOW IN
THE LOWER COUNTIES EAST OF BLAIR CO.

MSE

PAZ004>006-010>012-017>019-037-041-042-045-046-049>053-058-210400-

SPECIAL WEATHER STATEMENT - WINTER STORM WATCH
NATIONAL WEATHER SERVICE STATE COLLEGE PA
435 PM EST FRI MAR 20 1998

...A WINTER STORM WATCH IS IN EFFECT FOR SATURDAY INTO SATURDAY
NIGHT FOR MUCH OF NORTHERN AND CENTRAL PENNSYLVANIA...

A WINTER STORM WATCH IS IN EFFECT FOR SATURDAY FOR THE FOLLOWING
COUNTIES IN CENTRAL PENNSYLVANIA... WARREN... MCKEAN... POTTER...
ELK... CAMERON... NORTHERN CLINTON... CLEARFIELD... AND CENTRE.

A WINTER STORM WATCH IS IN EFFECT FOR SATURDAY AND SATURDAY NIGHT
FOR THE FOLLOWING COUNTIES IN CENTRAL PENNSYLVANIA...TIOGA...
LYCOMING... SULLIVAN... SOUTHERN CLINTON... UNION... SNYDER...
NORTHUMBERLAND... MONTOUR... COLUMBIA AND SCHUYLKILL.

A STORM WILL TRACK NORTHEAST FROM THE OHIO VALLEY TO EASTERN
MARYLAND BY LATE SATURDAY. RAIN WILL CHANGE TO SNOW ACROSS THE WATCH
AREA SATURDAY...WITH THE POTENTIAL FOR 6 INCHES OR MORE OF SNOW
ACROSS THE WATCH AREA BY LATE SATURDAY OR SATURDAY NIGHT.

THE CHANGE FROM RAIN TO SNOW WILL OCCUR AROUND DAYBREAK SATURDAY
ACROSS FAR NORTHERN PENNSYLVANIA. DURING THE DAY SATURDAY...THE
RAIN-SNOW LINE WILL PUSH SOUTH THROUGH CENTRAL PENNSYLVANIA. THE
SNOW WILL BEGIN TO ACCUMULATE OVER HIGHER ELEVATIONS FIRST. IN THE
VALLEYS...RELATIVELY WARM GROUND TEMPERATURES MAY KEEP THE SNOW FROM
ACCUMULATING HEAVILY UNTIL LATE IN THE DAY SATURDAY.

THE HEAVIEST ACCUMULATIONS WILL OCCUR AT ELEVATIONS OVER 1500 FEET
SATURDAY AND SATURDAY NIGHT...WHERE AMOUNTS WELL IN EXCESS OF 6
INCHES ARE POSSIBLE.

THIS HEAVY WET SNOWFALL MAY BRING DOWN TREE LIMBS...AND COULD ALSO
CAUSE POWER OUTAGES.

REMEMBER...A WINTER STORM WATCH MEANS THERE IS THE POSSIBILITY
OF SNOW ACCUMULATIONS OF SIX INCHES OR MORE.

STAY TUNED TO NOAA WEATHER RADIO OR OTHER MEDIA OUTLETS FOR FURTHER
STATEMENTS...ADVISORIES...AND POSSIBLE WARNING ON THIS UPCOMING BOUT
OF WINTER WEATHER.

SIMILAR INFORMATION CAN BE OBTAINED VIA THE STATE COLLEGE NATIONAL
WEATHER SERVICE WEB SITE AT  HTTP://IWIN.NWS.NOAA.GOV/IWIN/PA/PA.HTML

MSE