Area Forecast Discussion
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000 FXUS61 KPBZ 260016 AFDPBZ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 816 PM EDT MON APR 25 2016 .SYNOPSIS... A SOUTHWARD SAGGING FRONT IS INCREASING RAIN CHANCES FOR LATE TONIGHT AND TUESDAY. && .NEAR TERM /THROUGH TUESDAY/...
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RAIN CHANCES ARE ON THE INCREASE AS A SHORTWAVE AND ASSOCIATED COLD FRONT ENCROACH ON THE UPR OHIO REGION. AN UPDATE WAS ISSUED TO ADJUST POPS FOR THE LATEST RADAR TRENDS...AND TO ACCOUNT FOR MORE RAPID PROGRESSION OF THE OVERALL SYSTEM AS PER THE LATEST HIGH RES TRENDS. IN GENL...POPS ESCALATION TO LIKELY NUMBERS WAS MAINTAINED FOR THE SCENARIO WITH LESS THAN A HALF INCH OF RAINFALL ANTICIPATED GIVEN THE PROGRESSIVE SHORTWAVE SUPPORT AND RESULTANT FADE OF DYNAMICS. A THUNDER MENTION...ALBEIT SLGT CHC...WAS ALSO MAINTAINED GIVEN THE PROJECTED COOLING IN THE MID LVLS...BUT QUESTIONABLE SFC DEWPOINTS AND MORE RAPID FRONTAL PASSAGE AS MENTIONED ABOVE WOULD FURTHER LIMIT ALREADY MEAGER INSTABILITY FORECASTS FOR TUESDAY. AT ANY RATE...NO FURTHER ACTION WAS TAKEN WITH THE STORM PREDICTION CENTER MARGINAL RISK ASSESSMENT OVR AREAS ALONG AND SOUTH OF I 70 FOR TUESDAY AFTERNOON...WHICH IS IN RESPONSE TO THE STRONG SHEAR PROGNOSIS AND POSSIBLE DIURNAL DESTABILIZATION. A BLEND OF MODEL GUIDANCE WAS USED FOR THE NEAR TERM TEMPERATURE FORECAST.
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&& .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... PRECIP IS PROJECTED TO SHIFT WELL SOUTHWARD ON TUESDAY EVENING WITH THE SOUTHWARD SAGGING FRONT. BUILDING HIGH PRESSURE WITH DRY...COOL ADVECTION SHOULD ENSURE A DRY WEDNESDAY WITH NEAR-AVERAGE TEMPERATURE. RAIN CHANCES WILL QUICKLY RETURN THOUGH WITH LOW PRESSURE FORECAST TO ADVANCE OUT OF THE MIDWEST WITH WARM...MOIST ADVECTION ON ITS VAN. LIKELY TO CATEGORICAL POPS WERE MAINTAINED FOR PASSAGE OF THAT SYSTEM ON THURSDAY. BETTER RAINFALL AMOUNTS...A HALF TO THREE QUARTERS OF INCH...ARE ANTICIPATED OVR SRN ZONES GIVEN INITIAL CONVERGENCE IN VICINITY OF THE FRONTAL ZONE...BUT ANY SEVERE THREAT SHOULD BE PRECLUDED BY LIMITED INSTABILITY. && .LONG TERM /FRIDAY THROUGH MONDAY/... BUILDING HIGH PRES IN THE WAKE OF THE AFOREMENTIONED LOW IS PROGGED TO PROVIDE A DRY START TO THE WEEKEND...BUT ANOTHER SHORTWAVE TROUGH IS FORECAST TO DIG TOWARD THE MID ATLANTIC REGION AND INCRS PRECIP CHANCES FOR THE UPR OH REGION ONCE AGAIN. ACTUAL TRACK WL REMAIN QNABLE FOR A WHILE...SO SUPERBLEND GUIDANCE WAS EXCLUSIVELY UTILIZED FOR THE LONG TERM PERIOD. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... VFR IS EXPECTED MUCH OF TONIGHT AHEAD OF AN APPROACHING LOW PRESSURE. THE LOW AND ASSOCIATED COLD FRONT SHOULD CROSS THE RGN TUE...WITH INCREASING SHOWER AND MVFR POTENTIAL WITH ITS APPROACH AND PASSAGE. A FEW TSTMS ARE PSBL WITH FROPA WITH THE BEST CHCS TUE AFTN S OF PIT...WHERE A VCTS WAS MENTIONED IN THE TAF. A DEVELOPING LOW LVL JET SHOULD ALSO BRING A LLWS POTENTIAL OVERNIGHT MAINLY FOR PORTS FM PIT N. .OUTLOOK /TUESDAY NIGHT THROUGH SATURDAY/... RESTRICTIONS ARE PSBL TUE EVE S OF PIT AS THE FRONT EXITS. RESTRICTIONS ARE PSBL AGAIN THU/FRI WITH LOW PRESSURE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$

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