-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 251653
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1253 PM EDT SAT MAY 25 2013

.SYNOPSIS...
DRY AND COLD WEATHER CAN BE EXPECTED FOR THE WEEKEND.

&&

.NEAR TERM /THROUGH SUNDAY/...
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SURFACE HIGH WILL CONTINUE TO BUILD OVER THE REGION TODAY AS THE
UPPER LOW ROTATES OVER NEW ENGLAND. TIGHTENED PRESSURE GRADIENT
FLOW BETWEEN THE TWO SYSTEMS WILL ALLOW FOR SOME STRONGER
NORTHWESTERLY WINDS TO CONTINUE...ALTHOUGH FOCUSED A BIT FURTHER
EAST THAN YESTERDAY. BEYOND SOME SCATTERED DIURNAL CU...SOME HIGH
CIRRUS FROM A CONVECTIVE SYSTEM OFF TO THE WEST MAY MAKE IT INTO
THE WESTERN ZONES. HOWEVER...MOST OF THE FORECAST AREAS SHOULD SEE
A MOSTLY SUNNY DAY. DESPITE THE SUNSHINE...COLD NORTHWEST FLOW
WILL KEEP TEMPERATURES 10 TO 15 DEGREES BELOW SEASONAL NORMALS
ONCE AGAIN TODAY.

WITH BUILDING HIGH CONTINUING IT`S PROGRESSION EASTWARD...EXPECT
ANOTHER CALM CLEAR NIGHT TONIGHT. HOWEVER...WITH THE BOUNDARY
LAYER WARMING SLIGHTLY...FOCUS OF WIDESPREAD FROST/FREEZE HAS
SHIFTING A BIT FURTHER NORTH AND EAST. STILL ISOLATED POCKETS OF
FREEZING TEMPERATURES COULD OCCUR...ESPECIALLY IN THE MORE
SHELTERED VALLEYS IN THE HIGHER ELEVATIONS OF PA/WV/MD.

SUNDAY SHOULD ONCE AGAIN BE A QUITE WEATHER DAY WITH TEMPERATURES
MODERATING A FEW DEGREES CLOSER TO NORMAL. WIND GUSTS SHOULD
CONTINUE TO DIMINISH AS HIGH SETTLES OVERHEAD.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/...
HIGH PRES UNDR NW FLOW WL MAINTAIN DRY AND COOL CONDITIONS THROUGH
MOST OF THE SHORT TERM PERIOD. A GREAT LAKES SHRTWV IS EXPECTED TO
REINTIATE WARM ADVCTN BY MONDAY...AND TEMPS WERE MODERATED CLOSER
TO THE AVERAGES FOR THAT TIME FRAME.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MDLS DIFFER IN DEPICTIONS OF A RESUMPTION OF A WARM ADVCTN REGIME
FOR MONDAY NGT AND TUESDAY WITH NAM BEING THE MORE AGRESSIVE IN
TERMS OF PCPN POTENTIAL. AS CHC POPS WERE ALREADY INCLUDED WITH
THE CROSSING OF THE WARM FRONT...HAVE DECIDED TO PERSIST DESPITE
GFS AND ECMWF DRY SOLNS. HOWEVER...HAVE ADJUSTED TIMING BASED ON
THESE LATEST DETERMINISTIC TRENDS AND HAVE ALSO DIMINISHED POPS
FOR THE REMAINDER OF THE WEEK AS PER EXPECTATIONS OF WARM SECTOR
DOMINATION UNDR AN AMPLIFYING RIDGE.

TEMP RECOVERY WL BE DRAMATIC...WITH READINGS CONSERVATIVELY PROGGED
10 TO 15 DEGREES ABOVE THE SEASONAL AVERAGES FOR THE LATTER HALF
OF THE WEEK.

&&

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
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VFR CONDITIONS SHOULD CONTINUE FOR THE REMAINDER OF THE DAY AS
HIGH PRESSURE BUILDS EASTWARD. NOWRTHWEST WINDS 10-15 WITH GUSTS
TO 25 WILL BE POSSIBLE UNTIL AFTER SUNSET.

.OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
VFR CONDS EXPD WITH HIGH PRES IN CTRL THRU MON. SHWR/TSTM CHCS
RETURN WITH A WRMFNT MON NGT INTO WED.
-- End Changed Discussion --

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR MDZ001.
OH...FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR OHZ040-041-050.
PA...FREEZE WARNING FROM 2 AM TO 8 AM EDT SUNDAY FOR PAZ008-009-015-
     016.
     FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR PAZ007-013-014-
     020>023-029-073>076.
WV...FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR WVZ001-002-023-
     041.

&&

$$