Area Forecast Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KPBZ 062350
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
750 PM EDT FRI MAY 6 2016

.SYNOPSIS...
SHOWERS ARE EXPECTED PRIMARILY EAST OF PITTSBURGH DURING THE
AFTERNOON AND EARLY EVENING. A COLD FRONT WILL THEN BRING SHOWERS
AND ISOLATED THUNDERSTORMS SATURDAY AFTERNOON AND SATURDAY NIGHT.

&&

.NEAR TERM /THROUGH SATURDAY/...
ONE DEFORMATION BAND WHIRLING AROUND THE UPPER LOW TO OUR
SOUTHEAST IS SLOWLY BEING ERODED AS DRY AIR CONTINUALLY FEEDS
INTO THE LOW LEVELS FROM THE WEST UNDERNEATH IT. HI-RES GUIDANCE
IS HANDLING THIS UTTERLY ABHORRENTLY...AND LARGER SCALE DYNAMICAL
MODELS SEEM TO BE DOING A SUPERIOR JOB. THAT SAID...LIKELY RADAR
INITIALIZATION OF THE HI-RES MODELS IS THE CULPRIT FOR THIS DUE TO
THE EXPANSIVE VIRGA ON RADAR...AND AS SUCH THE FORECAST HAS
TRENDED MUCH MORE HEAVILY TOWARD THE NAM/GFS THAN THE HRRR/HRRRX.
THIS LEAVES METRO PITTSBURGH AS ABOUT THE FARTHEST WEST ANY
RAINFALL WILL MAKE IT THIS EVENING BEFORE THE DEFORMATION BAND
FALLS APART AND THE UPPER LOW SHIFTS EASTWARD.

IN THE WAKE OF THE UPPER LOW...CLEARING WILL LIKELY BECOME FAIRLY
ABUNDANT IN OHIO. OVERNIGHT LOWS WERE ADJUSTED DOWNWARD HERE DUE
TO A LACK OF CLOUDS AND LOWER DEWPOINTS. FRIES

PREVIOUS DISCUSSION FOLLOWS...DRY CONDITIONS WILL BE RELATIVELY
SHORT LIVED WITH A COLD FRONT MOVING INTO THE REGION FROM THE
NORTHWEST SATURDAY AFTERNOON. MADE RELATIVELY FEW CHANGES TO THE
TIMING OF PRECIPITATION...WITH MOST LOCATIONS RECEIVING RAIN
THROUGH THE LATE AFTERNOON. CONTINUED MENTION OF THUNDERSTORMS IN
ALL LOCATIONS...GOING WITH CHANCE THUNDER ACROSS THE SOUTHERN TWO
THIRDS OF THE AREA AS OPPOSED TO A SLIGHT CHANCE ACROSS THE NORTH.
HIGH TEMPERATURES WILL BE NEAR FRIDAYS HIGHS.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
COLD FRONT WILL COMPLETE ITS PASSAGE ACROSS THE REGION SATURDAY
EVENING...WITH RAIN RACING SOUTHEAST OF THE AREA AFTER MIDNIGHT.
THE AREA SHOULD REMAIN DRY ON SUNDAY...SPLIT BETWEEN LEFTOVER
SHOWERS ALONG THE FRONT TO THE SOUTH AND A SHORTWAVE TO THE NORTH.
THE CHANCE FOR SHOWERS WILL INCREASE LATE SUNDAY NIGHT INTO MONDAY
AS SATURDAYS COLD FRONT SHIFTS BACK NORTH AS A WARM FRONT.
HIGH TEMPERATURES WILL BE 5-10 DEGREES COOLER ON SUNDAY BEHIND
THE FRONT WITH VALUES REBOUNDING SLIGHTLY ON MONDAY.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
SHORTWAVES EMBEDDED IN SW FLOW AND ASSOCIATED SFC LOW PRESSURE
SHOULD BRING INCRG SHOWER/PSBL TSTM CHCS FOR THE FIRST HALF OF
THE WEEK. RIDGING SHOULD THEN RETURN MAINLY DRY WEATHER TO THE
RGN BY BEFORE A MIDWEST TROF APPROACHES LATE IN THE WEEK. TEMPS
SHOULD AVG A FEW DEGREES ABOVE SEASONAL LVLS THRU THE PERIOD.
SUPERBLEND GUIDANCE WAS USED...WITH SIGNIFICANT DOWNWARD
ADJUSTMENT TO POPS THU FOLLOWING RECENT MODEL TRENDS.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LIGHT RAIN ASSOCIATED WITH EAST COAST LOW PRESSURE SYSTEM ARE
BEGINNING TO DISSIPATE AS THEY ENCOUNTER MUCH DRIER AIR RESIDENT
OVER THE FORECAST AREA. DRY AIR WILL CONTINUE TO MAINTAIN VFR
CONDITIONS THROUGH AT LEAST LATE EVENING. AS THE LOW PULLS
AWAY...EASTERN PORTS LBE/DUJ MAY SEE A DROP IN CIGS LATE TONIGHT
INTO LOW MVFR OR IFR. OTHERWISE...ALL OTHER TERMINALS WILL REMAIN
VFR THROUGH MUCH OF SATURDAY.

RAIN SHOWERS AND THUNDERSTORMS ARE EXPECTED TO MOVE BACK INTO THE
AREA SATURDAY AFTERNOON WITH A FRONT DROPPING IN FROM THE
NORTHWEST. RESTRICTIONS ARE POSSIBLE WITH STRONGER SHOWER OR
THUNDERSTORM ACTIVITY.

NORTHERLY WINDS WILL GRADUALLY DISSIPATE...GOING LIGHT AND
VARIABLE AFTER SUNSET. SURFACE FLOW WILL THEN INCREASE FROM THE
SOUTHWEST SATURDAY AHEAD OF THE FRONT...BUT SHOULD GENERALLY STAY
BELOW 10KTS.
TAX


.OUTLOOK /SATURDAY THROUGH WEDNESDAY/...
RESTRICTIONS ARE LIKELY WITH A LATE MON/TUE WARM FRONT.

&&

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

&&

$$


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.