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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 260717
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
217 AM EST THU FEB 26 2015

.SYNOPSIS...
VERY LIGHT SNOW IS POSSIBLE OVER THE REGION TODAY AS LOW PRESSURE
MOVES OFF THE CAROLINA COAST AND THE UPPER JET STREAM FAVORS BROAD
BUT WEAK LIFT OVER THE STATE. THE UPPER LOW WILL CROSS THE STATE
ON FRIDAY. A LARGE AREA OF HIGH PRESSURE WILL BUILD ACROSS THE
AREA FOR THE FIRST PART OF THE WEEKEND. THE PATTERN WILL THEN
BECOME RATHER STORMY WITH A FRONTAL BOUNDARY WAGGLING NORTH AND
SOUTH OVER THE AREA INTO MID WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH CLOUDS NOW COVER THE AREA AND THE DOUGHNUT OF SNOW ALOFT
SHOULD SLOWLY CLOSE IN AS THE PRECIP WORKS DOWN TO THE SURFACE BY
SUNRISE RIGHT ALONG THE SRN BORDER. THE LEFT EXIT REGION OF THE
JET IS ALSO OVERHEAD AND THE FAVORABLE LIFT COULD PRODUCE FLURRIES
ACROSS THE ENTIRE AREA THIS MORNING. GFS WET VS MOST OTHER
MDLS/ENSEMBLE MEMBERS. HRRR AND RAP KEEP THE ACCUM PRECIP TO THE
FAR SE AND OVER THE NW MTNS. SO WILL KEEP THE LIKELY POPS CONFINED
TO THE FAR SE...MAINLY SRN LANCASTER/YORK COS. THE AMOUNTS THERE
WILL BE AN INCH OR LESS...WITH A DUSTING TO AN INCH IN MOST
PLACES ALONG THE MD BORDER AND IN THE LAURELS AND NW. THE WEAKNESS
IN THE LIFT AND PERSISTENT NORTHERLY FLOW TODAY WILL KEEP THE LOW
LEVELS VERY DRY IN THE CENTRAL AND NERN PARTS OF THE CWA.
THEREFORE...HAVE JUST PUT IN SOME FLURRIES THERE. THE LOW ZIPS
AWAY AND ANY SNOW IN THE SE SHOULD MOVE AWAY/STOP BY NOON. THE
WINDS BACK TO THE NW AND SOME SNOW SHOWERS WILL REMAIN IN THE WRN
MTNS ALL DAY. TEMPS SHOULD MOVE ONLY A FEW DEGS UP THROUGH THE
DAY.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
THE UPPER TROUGH AXIS MOVES OVERHEAD LATE TONIGHT AND FRIDAY
MORNING. NW WINDS WILL KEEP AN UPSLOPE GOING IN THE WEST AS WELL.
THUS...SNOW SHOWERS WILL BE POSSIBLE - MAINLY IN THE WEST AND
SOUTHERN HALF OF THE AREA THRU FRIDAY MORNING...AND HOLD ON IN THE
LAURELS THROUGH FRIDAY EVENING.

LOW TEMPS THURSDAY NIGHT WILL BE ZERO TO 5 BELOW ACROSS THE NRN
MTNS...AND UPPER SINGLE DIGITS TO LOWER TEENS ELSEWHERE. FRIDAY
MAXES WILL BE IN THE UPPER SINGLE DIGITS TO L-M20S.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE BUILDING INTO THE REGION DRIES THINGS OUT FOR EARLY
WEEKEND. AS IT MOVES TO THE ATLANTIC COAST ON SUNDAY...RETURN FLOW
SHOULD DRAW MOISTURE UP INTO THE OHIO VALLEY. MOISTURE WILL
OVERSPREAD THE OHIO VALLEY AND SLIDE ACROSS PA IN A DISORGANIZED
PRECIPITATION PATTERN. ANOTHER BLAST OF ARCTIC AIR THEN SHOVES
THAT SYSTEM OFF TO THE EAST.

AS A SOUTHWEST UPPER FLOW SETS UP NEXT WEEK...MOISTURE WILL SPREAD
TOWARD THE AREA BY LATER TUESDAY. COLD AIR IN PLACE OVER THE
RIDGE AND VALLEY REGION COULD LEAD TO THE INITIAL PRECIPITATION
SHIELD TO BE SLEET OR FREEZING RAIN. THE BULK OF THE MOISTURE DOES
APPEAR TO TRAVEL SOUTH OF PA AT THIS TIME. UNSETTLED CONDITIONS
WILL LINGER THROUGH LATE WEEK AS THE AREA WOBBLES AROUND THE ZERO
DEGREE H850 LINE..

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
A STORM SYSTEM OVER THE CAROLINAS WILL TRACK NORTHEAST TO CAPE
HATTERAS...THEN OUT TO SEA LATER TODAY. THE NORTHERN EDGE OF IT/S
PRECIP SHEILD COULD GRAZE KLNS WITH A BRIEF PERIOD OF LGT
SNOW/LOW VSBYS BTWN 12Z-15Z BASED ON LATEST NEAR TERM MDL
GUIDANCE. CONFIDENCE ABOUT 50/50 WHETHER KLNS SEES IFR VSBYS. CHC
OF IFR VSBY AT KMDT BTWN 12Z-15Z IS EVEN LOWER...BUT NOT ZERO.

COASTAL STORM WILL HAVE MADE IT/S CLOSEST PASS AND WILL BE
PULLING AWAY FROM THE AREA BY ARND 16Z. FOCUS WILL THEN SHIFT
TOWARD A WEAKER LOW PRES SYSTEM LIFTING NE FROM THE OHIO VALLEY.
LATEST MDL GUIDANCE SUGGESTS THIS SYSTEM WILL SPREAD LIGHT
SNOW/SIG VIS REDUCTIONS INTO THE NW MTNS /KBFD/ BY LATE AM...THEN
THE LAUREL HIGHLANDS /KJST/ DURING THE AFTN. PREDOMINANTLY IFR
CONDS APPEAR LIKELY AT THESE LOCATIONS INTO THIS EVENING...AS THE
SLOW-MOVING LOW PRES SYSTEM AND ASSOC LIGHT SNOW MOVES THRU. A
DOWNSLOPING NNW WIND SHOULD RESULT IN SOMEWHAT MORE FAVORABLE
CONDS EAST OF THE MTNS WITH WIDESPREAD MVFR CIGS AND OCNL LGT
SNOW. HOWEVER...CAN/T RULE OUT BRIEF IFR VIS REDUCTIONS THIS
EVENING AT KUNV/KAOO.

OUTLOOK...

FRI...EARLY AM LGT SNOW/VIS REDUCTIONS POSSIBLE.

SAT...NO SIG WX EXPECTED.

SUN...SNOW LIKELY NW MTNS. MIXED PRECIP POSSIBLE ELSEWHERE.

MON...MIXED PRECIP WITH CIG/VIS REDUCTIONS POSSIBLE...MAINLY AM.

&&

.CLIMATE...
THE COLDEST FEBRUARY ON RECORD IS STILL LOOKING LIKELY. MONTHLY
MEAN TEMPERATURES THROUGH THE 24TH...IPT 18.4...MDT 21.2.

&&

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

&&

$$
SYNOPSIS...DANGELO/LA CORTE
NEAR TERM...DANGELO
SHORT TERM...LAMBERT
LONG TERM...TYBURSKI
AVIATION...FITZGERALD
CLIMATE...