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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 252344
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
644 PM EST SUN JAN 25 2015

.SYNOPSIS...
LOW PRESSURE WILL BRING WIDESPREAD SNOW LATER TODAY THROUGH
MONDAY.

&&

.NEAR TERM /THROUGH MONDAY/...
LATEST WV IMAGERY SHOWS MID LEVEL LOW CENTER JUST OVER WESTERN KY
NOW SHIFTING EAST AS THE ASSOCIATED JET MAX SITS RIGHT OVER OR
EAST OF THE TROUGH AXIS. THE HRRR HAS BEEN HANDLING THINGS WELL SO
FAR TODAY AND OPTED TO MAKE MINOR CHANGES TO AMOUNTS AND LOCATIONS
OF MORE INTENSE SNOW THIS EVENING BASED ON LATEST RUNS.
OVERALL...VERY LITTLE CHANGE WAS NEEDED TO THE PREVIOUS FORECAST
AS LATEST RUNS HELD GOOD CONTINUITY. TEMPERATURES IN THE LOWER
LEVELS ARE SLIGHTLY WARMER SOUTH OF INTERSTATE 70 AND
CONSEQUENTLY THE CHANGEOVER TO SNOW MAY NOT BE UNTIL WELL AFTER
MIDNIGHT...SO AMOUNTS MAY NOT BE QUITE AS HIGH ACROSS THE SOUTHERN
FRINGE OF THE FORECAST AREA. TO THE NORTH WHERE PRECIPITATION WILL
BE ALL SNOW...ACCUMULATIONS ARE STILL EXPECTED TO RANGE FROM 4-6
INCHES THROUGH MONDAY WITH THE GREATEST AMOUNTS FROM PITTSBURGH
NORTH TO INTERSTATE 80 WHERE MODELS SHOW THE BEST DYNAMICS. THE
MOST INTENSE SNOWFALL RATES AREA EXPECTED TO OCCUR FROM EARLY THIS
EVENING UNTIL SHORTLY AFTER MIDNIGHT. THE WINTER WEATHER ADVISORY
WHICH COVERS THE ENTIRE FORECAST AREA WAS LEFT UNCHANGED. SNOW
WILL CONTINUE THROUGH MUCH OF MONDAY AS MOISTURE WRAPS AROUND THE
LOW AND ASSOCIATED INVERTED TROUGH SHIFTS NORTHEAST OVER THE REGION.;

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
UNSETTLED CONDITIONS WILL CONTINUE UNTIL HIGH PRESSURE BUILDS IN
BY WEDNESDAY MORNING. UNTIL THEN...SCATTERED SNOW SHOWERS WILL
PERSIST UNDER NORTHWESTERLY FLOW ALOFT AND A SUFFICIENTLY
DEEP BOUNDARY LAYER. TEMPERATURES WILL FALL TO APPROXIMATELY 10
DEGREES BELOW CLIMO NORMALS.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
WEDNESDAY AND WEDNESDAY NIGHT MAY BE THE ONLY DRY 24 HOUR PERIOD
FOR THE ENTIRE FORECAST AREA THROUGH THE SEVEN DAY FORECAST. HIGH
PRESSURE WILL MOVE ACROSS THE REGION ON WEDNESDAY...AND SHOULD
ALLOW FOR ONE PARTLY/MOSTLY SUNNY DAY.

FAST MOVING CLIPPER SYSTEM WILL BRING ANOTHER ROUND OF SNOW
THURSDAY INTO THURSDAY NIGHT WITH A WINTRY MIX POSSIBLE ALONG AND
SOUTH OF I-70. BUMPED UP POPS TO LIKELY FOR THIS SYSTEM. UPPER
LEVEL TROUGH WILL REMAIN IN PLACE INTO NEXT WEEKEND WITH WELL
BELOW NORMAL TEMPERATURES. SOME IMPORTANT TIMING DIFFERENCES FOR
NEXT WEEKEND WITH NEXT CLIPPER AND DELIVERY OF EVEN COLDER ARCTIC
AIR INTO THE UPPER OHO VALLEY. WPC PROGS LOOKS TO BE A GOOD
COMPROMISE WITH A CHANCE OF SNOW SHOWERS LATER SATURDAY THROUGH
SUNDAY.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
IFR/LIFR ALREADY IN PLACE ACROSS THE MAJORITY OF THE AREA...SAVE
STRANGELY ENOUGH FOR FKL/DUJ. THESE SITES WILL SINK TO IFR OVER
THE NEXT 2-3 HOURS. A PERIOD OF STEADY SNOW WITH IFR/LIFR VSBY
EXPECTED AREAWIDE OVERNIGHT...ALTHOUGH MGW WILL TAKE A FEW MORE
HOURS TO CHANGE OVER TO ALL SNOW. CANNOT RULE OUT SHORT PERIODS OF
VLIFR AS WELL. SNOW WILL CONTINUE PAST 12Z MONDAY BUT START TO
EASE A BIT...WITH IFR CONDITIONS CONTINUING. SOME SITES MAY
ACHIEVE LOW-END MVFR BY THE END OF THE TAF PERIOD...BUT CONFIDENCE
IS LOW.

.OUTLOOK.../MONDAY THROUGH FRIDAY/...
RESTRICTIONS IN SNOW WILL CONTINUE INTO TUESDAY. NEXT WIDESPREAD
RESTRICTIONS THURSDAY AFTERNOON INTO FRIDAY WITH A CLIPPER SYSTEM.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR MDZ001.
OH...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR OHZ039>041-
     048>050-057>059-068-069.
PA...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR PAZ007>009-
     013>016-020>023-029-031-073>076.
WV...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR WVZ001>004-
     012-021>023-041.

&&

$$