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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 071148
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
648 AM EST SAT DEC 7 2013

.SYNOPSIS...
HIGH PRESSURE WILL BUILD EAST INTO THE REGION TODAY THROUGH
TONIGHT...PROVIDING A BRIEF RESPITE FROM ACTIVE EARLY SEASON WINTER
WEATHER PATTERN. ANOTHER PERIOD OF FROZEN AND FREEZING
PRECIPITATION WILL ARRIVE SUNDAY AND CONTINUE INTO EARLY MONDAY.
AN ARCTIC FRONTAL PASSAGE EARLY NEXT WEEK WILL DROP TEMPERATURES
WELL BELOW NORMAL THROUGH THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
COLD POST FRONTAL NORTHWEST FLOW WILL DELIVER DRIER AIR OVER THE
COMMONWEALTH TODAY. STRATUS WILL HANG TOUGH ACROSS THE WEST AND
NORTH WHILE PARTLY TO MOSTLY SUNNY SKIES COVER THE SOUTH AND EAST.
INVERSION HEIGHTS AND UNFAVORABLE TRAJECTORIES WON`T SUPPORT ANY
SIGNIFICANT LAKE EFFECT SNOWFALL...BUT WILL LEAVE A CHC OF SNOW
SHOWERS IN THE WESTERN AND NORTHWESTERN MOUNTAINS.

HIGHS WILL BE MUCH COLDER THAN RECENT DAYS...RANGING ONLY FROM THE
MID 20S NORTHWEST TO THE MID TO UPPER 30S SOUTHEAST.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE WILL BECOME CENTERED OVER THE COMMONWEALTH TONIGHT...
BRINGING DECREASING LAKE CLOUDS NORTH AND CLEAR SKIES CENTRAL AND
SOUTH. MINS SHOULD RANGE FROM AROUND 10F NORTH TO THE LOWER 20S
SOUTHEAST.

COLD AIR DAMMING ASSOCIATED WITH DEPARTING EAST COAST SFC RIDGE
AXIS WILL BE OVERRUN BY A PERSISTENT SOUTHWEST UPPER FLOW WITH
EMBEDDED WEAK SYSTEMS AS THE DAY PROGRESSES ON SUNDAY.
PRECIPITATION WILL BREAK OUT BY LATE MORNING ACROSS THE SOUTH IN
THE FORM OF SNOW AND OVERSPREAD MOST AREAS NORTH OF I80 BY
EVENING. PRECIPITATION IS EXPECTED TO REMAIN ON THE LIGHT SIDE FOR
THE DAYTIME HOURS...WITH ONLY LIGHT ACCUMS OF SNOW EXPECTED. A
CHANGEOVER TO SLEET AND FREEZING RAIN IS POSSIBLE LATE IN THE DAY
NEAR THE MARYLAND BORDER OF THE LAUREL HIGHLANDS AND SOUTH CENTRAL
MOUNTAINS. HIGHS WILL STAY BELOW FREEZING THROUGHOUT...RANGING
FROM THE MID 20S NORTH TO THE LOWER 30S SOUTHEAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
WINTRY PRECIPITATION WILL CONTINUE SUNDAY NIGHT INTO MONDAY AS THE
FRONTAL ZONE AND AND STRONG UPPER JET WILL SHIFT OFF THE COAST
INTO THE MIDDLE OF THE WEEK...ALLOWING A VERY COLD AIRMASS TO
SPREAD INTO THE REGION FOR LATE IN THE PERIOD. QPF IS ONE QUESTION
AT THIS TIME...WITH ADVISORY AMOUNTS OF ICE SUGGESTED FOR MUCH OF
CENTRAL AND SOUTH CENTRAL PA. GIVEN THE 4TH AND 5TH PERIOD TIMING...
CONFIDENCE IS NOT HIGH ENOUGH FOR A WATCH ISSUANCE AT THIS TIME...
AS CONSENSUS SOLUTIONS INDICATE THE HEAVIEST MODEL QPF REMAINING
SOUTH OF THE MASON DIXON LINE.

AFTER THE SYSTEM ESITS THE REGION TO THE EAST BY MONDAY NIGHT...
A TRAILING WEAK WAVE MAY BRUSH THE AREA WITH SOME LIGHT SNOW ON
TUESDAY AFTERNOON AND EVENING BEFORE ARCTIC AIR SURGES INTO THE
REGION FOR THE REST OF THE WORK WEEK. ONLY MINOR CHANGES MADE TO
THE EXTENDED THIS MORNING...AS MOST FOCUS WAS ON THE DAY 1 AND DAY
2-3 SYSTEMS.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...

-- Changed Discussion --
NORTHWESTERLY FLOW BEHIND THE FRONT HAS ALLOWED FOR MVFR TO LIFR
CIGS AT BFD..AOO AND JST RESPECTIVELY. THE RESIDUAL LOW LEVEL
MOISTURE THAT IS POOLING TO ALLOW FOR THESE CLOUDS WILL CONTINUE
THROUGH THE FIRST HALF OF THE MORNING...BEFORE CLEARING OUT.
OVERALL IMPROVING CONDS ARE EXPECTED TODAY...AS THE MAIN SFC WAVE
MOVERS EAST OF THE REGION. VFR CONDITIONS WILL DOMINATE THROUGH
SUNDAY MORNING...WITH THE ONLY CAVEAT BEING UPSLOPE FLOW TONIGHT
AT BFD. THIS FLOW COULD ALLOW FOR MVFR CIGS BETWEEN 01 TO 09Z.

 THE NEXT SYSTEM WILL MOVE UP FROM THE SOUTH AND SHOULD BRING LOWERING
CIGS AND SNOW DEVELOPING SUNDAY AFTN. THE SNOW IS EXPECTED TO
CHANGE OVER TO A WINTRY MIX SUNDAY NIGHT AND THEN TO RAIN MONDAY
MORNING...BEFORE GRADUALLY TAPERING OFF MONDAY AFTERNOON.

OUTLOOK...

SUN...VFR WILL GIVE WAY TO MVFR/IFR AS THE NEXT ROUND OF WINTRY
PRECIP ARRIVES.

MON...WIDESPREAD MVFR/IFR ASSOCIATED WITH A PASSING COLD FRONT.

TUE-WED...WEST TO NORTHWEST FLOW DEVELOPING. COLD WITH SCT -SHSN
NORTH AND WEST.
-- End Changed Discussion --

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...DEVOIR/STEINBUGL
AVIATION...CERU/GARTNER