Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KPBZ 271747 AFDPBZ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 147 PM EDT MON APR 27 2015 .SYNOPSIS... AN UPPER LEVEL SYSTEM WILL SWING THROUGH THIS AFTERNOON. THIS WILL PROVIDE CLOUDS...SCATTERED RAIN OR SNOW SHOWERS AND COLDER TEMPERATURES. WARMER AIR MOVES BACK IN ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH 1230PM UPDATE...HAVE ADDED LIKELY POPS ACROSS MOST NON-OHIO COUNTIES. INSTEAD OF SHOWERS BEING MORE SCATTERED IN COVERAGE...A MORE WIDESPREAD AREA OF RAIN HAS DEVELOPED OVER WESTERN PENNSYLVANIA OVER THE LAST TWO HOURS. WOULD NOT BE SURPRISED IF THIS BRINGS A HALT TO ANY ADDITIONAL WARMING THROUGH THE REST OF THE DAY. PREVIOUS DISCUSSION FOLLOWS. IMPRESSIVE SHORTWAVE TROUGH WILL SWING THROUGH THE AREA TODAY... CIRCLING AROUND A LARGE UPPER LOW OFF THE NEW ENGLAND COAST. THIS WAVE WILL THICKEN CLOUDS...INCREASE PRECIPITATION CHANCES AND SPREAD COLDER AIR OVER THE ENTIRE REGION. THE RISK FOR SHOWERS WILL INCREASE AS THE DAY PROGRESSES DUE NOT ONLY TO THE WAVE SWINGING THROUGH...BUT ALSO TO THE RATHER COLD AIR ALOFT. THIS WILL CREATE A SCENARIO IN WHICH THE ATMOSPHERE DESTABILIZES QUICKLY. ADDITIONALLY...WITH THE COLDER AIR ALOFT...RAIN SHOWERS MAY AT TIME MIX WITH SNOW...OR PRECIPITATION MAY FALL AS GRAUPEL. THIS WILL BE ESPECIALLY TRUE OVER THE RIDGES WHERE THERMAL PROFILES BECOME COLD ENOUGH LATE IN THE DAY TO SUPPORT ALL SNOW ON THE HIGHEST PEAKS. TEMPERATURES WILL BE WELL BELOW SEASONABLE LEVELS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... BUILDING SURFACE HIGH PRESSURE UNDER NORTHERLY FLOW ALOFT WILL RESULT IN A DRY AND SEASONABLY COOL TUESDAY. CLOUDS WILL BE ON THE INCREASE SOUTH TO NORTH WEDNESDAY AS LOW PRESSURE MOVES TOWARD THE MID ATLANTIC STATES. TEMPERATURE THROUGH THE ENTIRE PERIOD A BLEND OF MOS WHICH IS NEAR 5 DEGREES BELOW THE SEASONAL AVERAGES. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
-- Changed Discussion --
CHANCE POPS DIMINISHING WEST TO EAST THURSDAY NIGHT AS SYSTEM MOVES OFF THE MID ATLANTIC COAST. BY FRIDAY AND THROUGH THE WEEKEND...MODEL DISCREPANCIES ON HANDLING UPPER LEVEL LOW OVER EAST COAST MAKE FOR A LOW CONFIDENCE FORECAST...AND CONTINUED TO FOLLOW NEWEST WPC PROGS INTO MONDAY.
-- End Changed Discussion --
&& .AVIATION /18Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
MVFR RESTRICTIONS EXPECTED UNTIL SHORTWAVE AND DEEPER MOISTURE SHIFT SOUTH AND EAST LATER TONIGHT...WITH QUICKER IMPROVEMENT CLOSER KZZV TO KHLG. IMPROVEMENT TO VFR EARLY TUESDAY AS DRIER AIR WORKS INTO REGION. NORTHWEST WINDS 5 TO 10 KTS THROUGH THE PERIOD WITH GUSTS TO 20 KTS THIS AFTERNOON. .OUTLOOK.../TUESDAY THROUGH SATURDAY/... THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH THURSDAY LOW PRESSURE.
-- End Changed Discussion --
&& .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.