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. --
717 FXUS61 KPBZ 291804 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 204 PM EDT Thu Sep 29 2016 .SYNOPSIS... Upper level low pressure will bring rain to our region for the rest of the week. && .NEAR TERM /THROUGH TONIGHT/... The afternoon update included the addition of a wind advisory for the higher elevations, and immediate downslope areas. The flash flood watch for Eastern Preston, Tucker, and Garrett Counties was continued. Deep, mature, stacked low pressure continues to spin over the Mid Ohio Valley with the surface occluded front analyzed as curving across East Central Ohio and Western WV. The systems mid level dry slot swept over the eastern zones and shunted widespread rain east, and northward. The Atlantic moisture stream is still expected to redevelop generally north of the PA turnpike turnpike, so categorical POPs for showers across those areas was maintained for the night with no problems anticipated for those areas. Convective development into Tucker, Garrett, and Preston counties will provide the main heavy rain/high water threat into Friday given flash flood guidance and upslope enhancement; hence, the continued flash flood watch after last nights band of 2 to 3 inch rainfall on the eastern slopes. In addition, shallow thunderstorms along the aforementioned front continue to pose a slight severe threat, with limitations imposed by instability questions. Areas west and south of Pittsburgh continue to be monitored given the magnitude of shear on the eastern flank of the parent low. The potential for high elevation and downslope wind gusts from roughly the Morgantown-to-Latrobe vicinities and eastward is sufficient for the inclusion of an overnight wind advisory in the afternoon package. Low inversion levels on model soundings and low level jet expectations may be limited by wind orientation and degraded mixing, but given the magnitude and projected height of the low level jet, this headline was initiated. && .SHORT TERM /FRIDAY THROUGH SUNDAY/... Showers and gusty wind will linger into Saturday as the nearly stationary mature low pressure system gradually fills. As the low dislodges and slowly creeps northward Saturday, rain will become increasingly scattered. No real changes were made for this forecast period other than to tweak POPs and temperature based on Superblend guidance. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... Building high pressure is forecast to return drier and warmer weather as the week progresses. Superblend guidance, tweaked for POP continuity, was also used for this period. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... An upper low aloft will move bands of showers across ports into the evening, with variable conditions in and out of the bands. In general deeper moisture in place at KDUJ where IFR should remain in place through much of the period. Elsewhere areas of MVFR will gradually improve to VFR overnight into Friday as drier air is wrapped into and around the upper low. Strengthening pressure gradient will strengthen winds with gusts over 20kts most locations through the afternoon, and possible gust toward 30kts at KLBE in downslope.. .OUTLOOK /FRIDAY NIGHT THROUGH MONDAY/... Scattered restrictions can be expected into Monday as the upper level low lingers, then slowly lifts north of the region. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...Wind Advisory from 6 PM this evening to noon EDT Friday FOR MDZ001. Flash Flood Watch through Friday afternoon FOR MDZ001. OH...None. PA...Wind Advisory from 6 PM this evening to noon EDT Friday FOR PAZ073>076. WV...Wind Advisory from 6 PM this evening to noon EDT Friday FOR WVZ510>514. Flash Flood Watch through Friday afternoon FOR WVZ512>514. && $$ 15/10 is the U.S. government's official web portal to all federal, state and local government web resources and services.