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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KPBZ 070009 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 709 PM EST Tue Dec 6 2016 .SYNOPSIS... Low pressure is expected to spread precipitation across the region through early tonight. A Thursday cold front will return snow shower chances and much colder temperatures for the end of the week and into the weekend. && .NEAR TERM /THROUGH WEDNESDAY/... 620pm update... Precipitation dissipating quickly from west to east and expect this trend to continue through the evening hours. In addition to the decaying precipitation, seeing a surge of warmer air at the surface, especially over Ohio and Northern West Virginia. The evaporation of rain is due to the fact that the inland surface low, responsible for today`s activity, is phasing toward the coast and the main surface low near the Chesapeake Bay will soon take over. The push of warmer air is the last of the warm air advection around the inland low, as surface winds swing to the south and southwest. This final surge of warmer air will likely end soon with the loss of the inland low. For this update, have removed PoPs faster and also adjusted temperatures to more closely represent current conditions and those overnight. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... Lingering low level moisture over the eastern zones may cause light precipitation early Wednesday. Otherwise, dry weather is forecast for as surface high pressure builds across the region briefly. The next cold front is still expected to cross on Thursday, bringing the coldest air of the season so far. Have increased PoPs for snow showers behind the front in the developing mid-level trough. Latest guidance shows favorable lake enhancement snow to develop mostly over the the north for a short period of time. After the initial onslaught of the cold front and blustery snow showers late Thursday, inversion heights will gradually lower and decrease the snow accumulation rate by late Friday. Nonetheless, stagnant low level moisture and lowering dendritic growth zone is expected to keep snow chances lasting through the start of the weekend, especially over the higher terrain. Temperatures will lower to below normal values by the end of the period and wind chill values are expected to decrease to near single digits. && .LONG TERM /SATURDAY THROUGH TUESDAY/... The cold-supporting upper trough over the Eastern CONUS is progged to fill rapidly early next week as another low develops toward the Great Lakes. Flow over the Upper Ohio will thus deamplify and temperature moderate back toward the seasonal averages. Best precip chances look to be on Sunday night and into Monday as that Great Lakes low drags a front across the region. With the low-center forecast well north of the region, precip timing will depend on eventual frontal progress. Superblend guidance was used for long term forecast construction. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
IFR cig restrictions look likely to persist through the night despite building high pressure with ample low-level moisture and cooler air moving in aloft. TAFs were constructed with a nod to all short-term guidance which shows improvement to low IFR shortly after midnight but may opt to amend and extend IFR cigs to mid-morning and improvement to VFR to mid-afternoon if rapid update models and upstream trends support the idea. .OUTLOOK... Periodic restrictions are likely for the rest of the week as a strong cold front sweeps the region.
-- End Changed Discussion --
&& .PBZ WATCHES/WARNINGS/ADVISORIES... MD...Winter Storm Warning until midnight EST tonight FOR MDZ001. OH...None. PA...Winter Storm Warning until midnight EST tonight FOR PAZ074-076. WV...Winter Weather Advisory until 10 PM EST this evening FOR WVZ512>514. && $$ is the U.S. government's official web portal to all federal, state and local government web resources and services.