Area Forecast Discussion
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FXUS61 KPBZ 200614
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
114 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$





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