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. --
000 FXUS61 KPBZ 261329 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 929 AM EDT Wed Apr 26 2017 .SYNOPSIS... Warm, dry weather will be interrupted by showers and storms with a weak Thursday front. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
No major changes needed this morning outside of minor adjustments to daytime high temperatures. Previous discussion follows.. Quiet weather is anticipated through tonight as high pressure slides across the region in response to a digging Plains trough. Insolation and warm advection under that ridge will support a significant warmup today. Readings will be some 10 to 20 degrees warmer than yesterday, with many locations reaching or topping 80 degrees. Some high clouds may arrive later tonight, and with lower levels remaining mixed due to an increasing tight pressure gradient, temperatures will remain mild overnight, with lows temperatures around 15 degrees above seasonal averages.
-- End Changed Discussion --
&& .SHORT TERM /THURSDAY THROUGH FRIDAY/... Main event this period is still the ejection of the Plains trough into the Great Lakes by Thursday afternoon. This negatively tilted feature will push a frontal boundary across the CWA during the late afternoon/early evening. Exact timing remains a bit problematic, and appears to be a touch faster on latest model runs. Have maintained mostly likely PoPs for this event. The severe threat remains somewhat uncertain. While deep layer shear will certainly be present in the forecast pattern, instability is the main question. Given afternoon temperatures in the lower to mid 80s across much of the area with upper 50s dewpoints, think that instability may be sufficient to overcome mid-level capping, which could be mitigated by mid to late afternoon anyway as cooler 700 mb temperatures arrive. Overall, think that BUFKIT soundings may be underplaying the potential CAPE. SPC has expanded a marginal risk over most of our area in the new day 2 outlook, and would not be surprised to see higher probabilities in later updates. Will maintain the HWO mention of severe risk. Precipitation pulls out behind the front during the evening hours. Dry weather returns for Friday with high pressure. Although temperatures will moderate a bit, broad southwest flow aloft points to continued above normal temperatures. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... An active pattern is figured for the weekend into early next week. A few shortwaves will cross in continued moist southwest flow along the front of a broad trough, leading to rain chances for Saturday and Sunday. Timing remains tricky, but Saturday night currently looks to be the period with the lowest coverage in the warm sector. Temperatures remain above normal. The trough lifts out as a closed upper low into the Great Lakes by Monday, pushing a fairly strong boundary across us. Given system strength, the amount of moisture, and a possibly negative tilt to the upper trough, strong storms appear possible. Behind this system, quieter weather and seasonable temperatures are expected into the middle of next week. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... Primarily MVFR fog and stratus will blanket ports east of PIT into mid morning. Insolation will quickly mix out fog in other areas with gradual improvement to VFR expected as the morning progresses. .Outlook... Restriction are possible as a weak front generates thunderstorms late on Thursday. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...None. OH...None. PA...None. WV...None. && $$ is the U.S. government's official web portal to all federal, state and local government web resources and services.