Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Graphics & Text | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
313 FXUS61 KPBZ 071942 AFDPBZ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 242 PM EST SUN FEB 7 2016 .SYNOPSIS...
-- Changed Discussion --
LOW PRESSURE IS POISED TO SPREAD RAIN AND SNOW OVER THE REGION ON MONDAY...AND SNOW ON TUESDAY AND WEDNESDAY.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
THE UPR OH REGION IS EXPECTED TO REMAIN DRY THROUGH MIDNGT WITH RIDGING BETWEEN WRN GREAT LAKES AND SERN COASTAL LOW PRESSURE SYSTEMS. TEMPERATURES WILL ONCE AGAIN BE ABOVE SEASONAL AVERAGES. THE WRN LOW WL BE THE PROBLEM FOR THE NXT FEW DAYS AS IT IS FORECAST TO DEEPEN OVR THE MIDWEST AND PLAGUE THE ARE WITH BROAD ASCENT...DEEP MOISTURE...WITH SHORTWAVE SUPPORT ROTATING ARND THE CUTOFF LOW. FOR TONIGHT...MOISTURE AND ASCENT VIA WARM ADVCTN AND WEAKLY DIVERGENT FLOW ALOFT ARE LIKELY TO SUPPORT PRECIPITATION DEVELOPMENT OVER WESTERN ZONES TOWARD MORNING...WITH EASTWARD PROGRESSION AFTER DAYBREAK MONDAY AS PER SLOWER MDL CONSENSUS. AS THAT SOLN SEEMS REASONABLE GIVEN SBSDNC ON THE WRN FLANK OF THE EXPLODING SE COAST/WRN ATLANTIC LOW...HAVE ADJUSTED GRIDS FOR THAT SCENARIO AND RETREATED FROM OVRNGT POPS. PRECIP TYPE REMAINS AN ISSUE GIVEN THE AFOREMENTIONED WARM ADVECTION AND LINGERING BOUNDARY LAYER WARMTH. EXPECT A RAIN/SNOW OR A PRIMARY SNOW SITUATION WITH MELTING AT THE SFC AS THE SYSTEMS COLD FRONT PLOUGHS TOWARD THE I 77 CORRIDOR DURING THE PREDAWN HOURS. GIVEN THE TEMP LIMITATIONS AND SLOWER PROGRESSION...ANY LIGHT ACCUMULATION IS NOT EXPECTED TO BE PROBLEMATIC FOR THE RUSH HOUR.
-- End Changed Discussion --
&& .SHORT TERM /MONDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
IN GENERAL FOR THE THREE-DAY SHORT TERM PERIOD...EXPECT PERIODIC SNOW SHOWERS AND PROLONGED ACCUMULATION OF SEVERAL INCHES...WITH MORE SIGNIFICANT NUMBERS ON THE RIDGES. A HAZARDOUS WEATHER OUTLOOK MENTION FOR POSSIBLE ADVISORIES HAS BEEN MAINTAINED AND HEADLINE POTENTIAL WILL BE FURTHER EVALUATED BY SUBSEQUENT SHIFTS. THE MARGINAL TEMPERATURE PROFILE AND WARM BOUNDARY LAYER ON THE EASTERN SIDE OF THE SYSTEM ARE LIKELY TO CONTINUE COMPROMISING SNOW POTENTIAL AND PRECLUDE MUCH IN THE WAY OF ACCUMULATIONS THROUGH MONDAY. HOWEVER...THE SYSTEMS FRONTAL PASSAGE WILL USHER IN A COLDER AIRMASS BY MONDAY NIGHT AND ANY LINGERING RAIN SHOWERS...OR RAPIDLY MELTING SNOW SHOWERS...WILL HAVE BETTER ACCUMULATION POTENTIAL AS NIGHT FALLS. FORTUNATELY...THE ENCROACHMENT OF THE MID LVL LOW CENTER SHOULD SUFFICIENTLY WEAKEN THE WIND/FRONTOGENESIS POTENTIAL AND OVERALL ASCENT FIELDS TO OFFSET THE IMPROVED TEMPERATURE PROFILE FOR SNOW. THE FORECAST REMAINS OF PROLONGED SNOW SHOWER POTENTIAL THROUGH TUESDAY WITH RELATIVELY MINOR ACCUMULATIONS. THE EXCEPTION...AS ALWAYS...WILL BE THE RIDGES...WHERE OROGRAPHIC SUPPORT SHOULD PROMOTE MORE SIGNIFICANT ACCUMULATION. BY WEDNESDAY...THE CUTOFF LOW IS FORECAST TO BE FILLED/PHASED WITH THE UPR OH UNDER THE AXIS OF A HIGH-AMPLITUDE ERN CONUS TROUGH. SNOW SHOWER POTENTIAL WILL THUS CONTINUE AS INCREASINGLY COLDER AIR IS POISED TO FLOW OVR THE REGION AS THAT AXIS SHIFTS EWD. IN ADDITION...THE LATEST DETERMINISTIC TREND IS TO ROTATE A VORT CENTER/SHORTWAVE INTO THE BASE OF THAT LOW. PRECIP PROBS WERE THUS INCRSD FOR WEDNESDAY...CUMULATING IN CATEGORICAL NUMBERS FOR THE HIGHER ELEVATIONS...BUT DRY ADVCTN AND INCREASING COLD IN THE SNOW-SOURCE REGION SHOULD DEGRADE EFFICIENCY SO TOTALS WERE NOT AMPED MUCH AT THIS STAGE OF THE FORECAST PROCESS.
-- End Changed Discussion --
&& .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
-- Changed Discussion --
THE AFOREMENTIONED UPPER TROUGHING PTN IS PROGGED TO CONTINUE FUNNELING COLD AIR OVR THE AREA THROUGH THE WEEKEND. SUB AVG TEMPS CAN BE EXPECTED WITH READINGS ABOUT 20 DEGREES UNDER THE NORMALS ANTICIPATED BY THE WEEKEND. THE I 80 CORRIDOR AND RIDGE ZONES WL HAVE THE BETTER SNOW SHOWER POTENTIAL DURING THIS PERIOD GIVEN THE COLD ...OFF-THE-LAKES UPSLOPING FLOW. THE LONG TERM WAS CONSTRUCTED USING THE SUPERBLEND GUIDANCE.
-- End Changed Discussion --
&& .AVIATION /19Z SUNDAY THROUGH FRIDAY/... VFR WILL CONT TDA ALTHOUGH MID LVL CLOUDS WL INCRS LATER AHD OF AN APPROACHING COLD FRONT. MVFR/PATCHY IFR IN RAIN AND SNOW IS EXPD FOR PORTS W OF PIT BY SUNRISE MON MRNG...WITH PCPN/CONDITION DETERIORATION SPREADING E THRU THE DAY AS THE FRONT ADVANCES. .OUTLOOK.../TUESDAY THROUGH FRIDAY/... RESTRICTIONS CAN BE EXPECTED THROUGH THU WITH THE AREA UNDR UPR TROFG. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$ 15/07

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