Area Forecast Discussion
Issued by NWS State College, PA

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 KCTP 291800 AFDCTP Area Forecast Discussion National Weather Service State College PA 200 PM EDT FRI JUL 29 2016 .SYNOPSIS... An upper level trough will influence the region through early next week...bringing daily chances of scattered showers and thunderstorms. Most of the time will be dry in any one location however. high pressure will build over the northeastern united states by mid to late next week. && .NEAR TERM /THROUGH TONIGHT/... Mostly sunny skies with temperatures in the 80s this afternoon. There are a few showers around the most organized areas are in northwestern PA with a few rogue showers in central PA. CAMS forecasts allowed for depicting convection in northwest where PoPs are highest in forecast. Did not try to forecast rogue showers in central areas. Most activity should die off this evening as we lose the instability. Then patchy fog, favored in areas of recent rainfall. Low mainly in the 60s some warmer spots in southeast and cooler in northwest. && .SHORT TERM /SATURDAY/... Most guidance continues to show the plume of high PW air coming into PA Saturday. This favors increased chance of showers and thunderstorms. Each hydrostatic model and it`s convective parameterization scheme (CPS) have a different idea on the evolution. The high PW air and SW flow favors the chance of rain. The 12Z NAM maybe a excessive later Saturday into Sunday. At this time the GEFS 0.5 degree data implies the chance of rain increases rapidly after 11 AM Saturday and keeps climbing. It of course has a big wet bias in convective cases. The GEFS and all the blends imply lowest PoPs in northwest and west and higher central to eastern areas. GEFS is basically showing rain over all of eastern and central PA by 21Z. Expect showers and thunderstorms with areas affected by intense cores to see some better rainfall amounts. Most areas should not see the widespread 0.5 to 1.0 inch amounts. The rainfall peaks in the SREF/GEFS shortly after the CAPE peaks. This implies mostly convective and CPS is biasing forecasts. The most intense rainfall is forecast mainly after 21Z and early overnight Saturday which is mainly in the next forecast period. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... A second wave moves through in cyclonic flow Saturday night and Sunday keeping the POPs in the 50-70 range with highest chances over the eastern counties. Short-wave moves to the coast Sunday night with ridging building in across Central PA helping clear things out.Monday should be a drier day with sunshine and temps in the 80s.Hi pres ridge should hold through Wednesday though the GFS tries to indicate maybe an isolated afternoon/evening shower or thunderstorm over the Laurel Highlands both days. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR all about the air space. Issues this afternoon include some very isolated rogue showers in central PA and more organized showers in northwestern PA. Check radar before takeoff as some of these showers will develop into thunderstorms. Models imply rain and showers move in Saturday into Saturday night. Shower with lower visibility and ceilings along with isolated thunderstorms will be an issue from about midday Saturday through midnight. Then more IFR in patchy fog where it rains. OUTLOOK... SAT...Showers and isolated TSTMS IFR/MVFR then overnight fog. SUN-Mon...Scattered showers and isolated thunder. TUE...Improving conditions. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...DeVoir/Fitzgerald NEAR TERM...Grumm SHORT TERM...Grumm LONG TERM...Watson AVIATION...Grumm is the U.S. government's official web portal to all federal, state and local government web resources and services.