462 
FXUS61 KPBZ 251034
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
634 AM EDT SAT MAY 25 2013

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

&&

.NEAR TERM /THROUGH TONIGHT/...
TEMP DROP OVR AREAS N AND E OF PIT HAS BEEN RETARDED THIS MRNG BY
SCT TO BKN STRATOCU DECK THAT HAS RECOVERED SINCE MIDNGT.
NEVERTHELESS...SOME LOCATIONS HAVE ALREADY REACHED THE FREEZING
MARK AND THE REST CONT TO FLIRT WITH THE THRESHOLD. THE REMAINDER
OF THE AREA COUNTIES ARE IN THE MID 30S FOR THE MOST PART WITH
DEWPOINTS IN THE LOWER 30S. FROST AND FREEZE HEADLINE WL THUS BE
MAINTAINED UNTIL SHORTLY AFTER DAYBREAK.

AS UPR/MID LVL TROF AXIS HAS DUG TWD THE COAST...COLD NW FLOW OVR THE
UPR OH REGION...WITH HIGH PRES ON THE SFC...WL MAINTAIN SUB-AVERAGE
TEMPS TDA...WHICH WERE FORECAST 10 TO 15 DEG UNDR USING A BLEND OF
ALREADY-CLOSE GUIDANCE.

EXPECT SOME HIGH-BASED STRATOCU TO FORM THIS AFTN AS PROGGED
CONVECTIVE TEMPS SHOULD BE EXCEEDED...BUT ONLY SCT COVERAGE IS
ANTICIPATED GIVEN THE FORECAST TEMP/DP SPREADS.

THE SFC HIGH PRES AXIS IS EXPECTED TO SLIDE FURTHER EWD OVR THE
AREA TNGT. ANOTHER COLD NGT IS THUS ANTICIPATED...BUT HEADLINES
HAVE BEEN SHIFTED EWD ALSO...WITH A SMALLER FREEZE AREA LIMITED TO
THE NRN ZONES GIVEN PROGNOSIS OF AN OVRALL WARMER COLUMN. DAY
SHIFT MAY HAVE TO ADJUST AS RADIATION CONDITIONS MAY SPPRT A MORE
EXPANDED AREA...ESPECIALLY ACRS THE RIDGES.

&&

.SHORT TERM /SUNDAY 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 /12Z SATURDAY THROUGH WEDNESDAY/...
PTCHY IFR IN BR/STRATUS HAS DVLPD ACRS THE FKL/DUJ AREA...AS WELL
AS HLG. THIS SHOULD QUICKLY END THIS MRNG AS DRIER AIR ALOFT MIXES
DOWN. OTRW MCLR SKIES AND NW WNDS GUSTING TO 20-25KT EXPD FOR TDA.

.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.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR MDZ001.
     FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR MDZ001.
OH...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR OHZ039>041-
     048>050-057>059-068-069.
     FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR OHZ040-041-050.
PA...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ020-021-029-
     031-073-075.
     FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR PAZ007-013-014-
     020>023-029-073>076.
     FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR PAZ007>009-
     013>016-022-023-074-076.
     FREEZE WARNING FROM 2 AM TO 8 AM EDT SUNDAY FOR PAZ008-009-015-
     016.
WV...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR WVZ001>004-012-
     021-022.
     FROST ADVISORY FROM 2 AM TO 8 AM EDT SUNDAY FOR WVZ001-002-023-
     041.
     FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR WVZ023-041.

&&

$$

15/07