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 140205 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 905 PM EST Fri Jan 13 2017 .SYNOPSIS... A wintry mix of precipitation will be possible both Saturday and Sunday night into Monday morning. Well above normal temperatures are then expected by the middle of next week. && .NEAR TERM /THROUGH SATURDAY/...
-- Changed Discussion --
With 9pm update, primary changes were to timing of precipitation, especially determining the northern extent. Although the closest automated observing sites reporting rain at 9pm were Cincinnati and Charleston, mPING reports as well as observations slightly north of the Wilmington forecast office suggest that some light freezing rain is falling closer to our forecast area. Although widespread precipitation may be delayed by a couple of hours considering upstream observations and latest high-resolution models, decided that the chance for light precipitation was high enough to not delay the start of the freezing rain advisories that go into effect at 11pm. Previous discussion follows. Precipitation is expected to develop overnight across the southern third of the forecast area as a shortwave passes and the entrance region of a 150kt jet core slowly transitions over the area. Model guidance has continued to trend south with the best dynamics and overall made minimal change needed to the inherited forecast. Soundings indicate favorable profile for freezing rain overnight and into the morning for locations south of Pittsburgh and lasting for much of the day across Garrett county as winds maintain a southeasterly component unfavorable favorable for scouring out colder valley air in place. No changes were made to previously issued freezing rain advisories. Temperature grids were modified by blending in latest bias correct EKDMOS and manual adjustments to valley temperatures in Garrett and Tucker counties.
-- End Changed Discussion --
&& .SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/... Passage of that shortwave on Saturday eve will diminish any precip and pull the front southward again. Temperature very near the average is again anticipated for Saturday night and Sunday as surface high pressure settles over the region under zonal flow aloft. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... A deeper trough is progged to develop over the plains for the start of the new week. Warmer weather under the resulting rising heights over the Upper Ohio Region may be preceded by some additional freezing rain in the predawn of Monday. That HWO mention was maintained. Warmer weather is then expected to dominate once again until the trough ejects and drags a front toward the area late in the period. Superblend guidance represented this scenario well and was deviated from only in POP timing. && .AVIATION /02Z SATURDAY THROUGH WEDNESDAY/... Models continue to tighten the gradient of precipitation across the region, as surface ridge strengthens over Ontario and Quebec, while a surface wave moves along boundary south of the Upper Ohio Valley. A deterioration to MVFR looks to occur over ports south of KPIT late tonight into early Saturday with a wintry mix lowering vsby to IFR at times. Still believe a brief mix with sleet possible at KPIT early Saturday afternoon, but this will be on the northern fringe of a sharp cutoff in deeper moisture, and only MVFR CIGs forecast for now. Ports north of KPIT will remain VFR through the period. As wave exits Saturday afternoon IFR cigs across the south will remain, with general VFR elsewhere. .OUTLOOK... VFR Sunday under high pressure. Periodic restrictions are then expected early next week as a series of disturbances cross the region. && .PBZ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...Freezing Rain Advisory until 7 PM EST Saturday FOR MDZ001. OH...Freezing Rain Advisory until 1 PM EST Saturday FOR OHZ057>059- 068-069. PA...Freezing Rain Advisory until 1 PM EST Saturday FOR PAZ031-075. Freezing Rain Advisory until 7 PM EST Saturday FOR PAZ074-076. WV...Freezing Rain Advisory until 1 PM EST Saturday FOR WVZ004-012- 021-509. Freezing Rain Advisory until 7 PM EST Saturday FOR WVZ510>514.
-- End Changed Discussion --
&& $$ is the U.S. government's official web portal to all federal, state and local government web resources and services.