Area Forecast Discussion
Issued by NWS

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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KPBZ 061521 AFDPBZ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 1021 AM EST SAT FEB 6 2016 .SYNOPSIS... WARM TEMPERATURES ARE EXPECTED THROUGH THE WEEKEND. LOW PRESSURE WILL SPREAD RAIN AND SNOW OVER THE REGION ON MONDAY AND TUESDAY. && .NEAR TERM /THROUGH SUNDAY/... WARM ADVECTION AND INSOLATION IN ADVANCE OF A DRY SHORTWAVE TROUGH WILL DRIVE TEMPERATURES ABOUT 7 DEGREES ABOVE THE AVERAGES TODAY. THAT TROUGH WILL CROSS THE AREA TONIGHT. MOISTURE AND ASCENT WITH THAT FEATURE WILL BE LACKING...SO NO PRECIP IS ANTICIPATED AND THE DISTURBANCE IS TOO WEAK TO PULL COLDER AIR OVR THE REGION...HENCE OVRNGT LOWS WILL NOT BE FAR OFF THE AVERAGES. RIDGING BETWEEN UPR MS VALLEY AND SERN U.S. LOW PRESSURE SYSTEMS WILL SUPPORT A DRY SUNDAY WITH FURTHER...ALBEIT MINOR...MODERATION OF TEMPERATURE. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... THE UPR MS LOW IS CURRENTLY FORECAST TO DEEPEN OVR THE GREAT LAKES AND MIDWEST...HENCE AMPLIFYING THE SOUTHWEST...TO SOUTHERLY FLOW OVR THE UPR OH FOR SUNDAY NIGHT AND MONDAY. IMPROVED MOISTURE AND ASCENT FIELDS WILL THUS SUPPORT INCREASED PRECIP PROBS OVER WESTERN ZONES ON SUNDAY NIGHT WITH EASTWARD ENHANCEMENT ON MONDAY. THE MARGINAL TEMP PROFILE AND WARM BOUNDARY LAYER IN THE WARM ADVECTION REGIME ON THE EASTERN FLANK OF THAT SYSTEM SHOULD COMPROMISE SNOW POTENTIAL AND PRECLUDE SERIOUS ACCUMULATION THROUGH MONDAY...HOWEVER...THE SYSTEMS FRONTAL PASSAGE WILL DECISIVELY CHANGE THE TEMP PROFILE AS NIGHT FALLS ACCORDING TO CURRENT TIMING. FORTUNATELY...THE ENCROACHMENT OF THE MID/UPR LOW CENTER SHOULD SUFFICIENTLY WEAKEN THE WIND AND OVRALL ASCENT FIELDS AND THUS COMPROMISE THE IMPROVED TEMP PROFILE FOR SNOW. THE FORECAST IS THUS OF PROLONGED SNOW SHOWER POTENTIAL THROUGH TUESDAY WITH RELATIVELY MINOR ACCUMULATION. THE EXCEPTION LOOKS TO BE THE RIDGES AS USUAL WHERE OROGRAPHIC SUPPORT SHOULD SUPPORT MORE SIGNIFICANT ACCUMULATION. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... THE AFOREMENTIONED LOW IS GFS/ECMWF FORECAST TO CUTOFF AND DEVELOP EASTWARD BEFORE FILLING/PHASING INTO THE LONGWAVE PATTERN BY MIDWEEK. NEVERTHELESS...OVERALL UPPER TROUGHING IS PROGGED OVR THE GREAT LAKES/UPR OHIO REGION FOR THE LONG-TERM PERIOD...WITH AMPLIFICATION INDICATED TOWARD THE WEEKEND. SUB-AVG TEMPS AND PERSISTENT SNOW SHOWER CHANCES WERE MAINTAINED FOR THE PERIOD...WITH FOCUS TOWARD THE I-80 CORRIDOR AND RIDGES DURING THE LATTER HALF OF THE WEEK. THE LONG TERM WAS CONSTRUCTED USING THE SUPERBLEND GUIDANCE. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... VFR CONDITIONS ARE EXPD THRU SUN...THOUGH A WEAK GT LKS SHORTWAVE WILL BRING OCNL MID LVL CLOUDS TODAY. .OUTLOOK.../SUNDAY NIGHT THROUGH WEDNESDAY/... RESTRICTIONS ARE EXPD WITH A SUN NGT/MON COLD FRONT AND SUBSEQUENT UPR TROFG THRU MID WEEK. && .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.