Area Forecast Discussion
Issued by NWS State College, PA

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000 FXUS61 KCTP 260540 AFDCTP Area Forecast Discussion National Weather Service State College PA 140 AM EDT THU MAY 26 2016 .SYNOPSIS... A ridge of high pressure will set up shop over the western Atlantic for the next several days bringing warm and increasingly humid conditions to the region into the holiday weekend. Cooler and showery weather may arrive for Memorial Day. && .NEAR TERM /THROUGH TODAY/... Lots of high and mid clouds out there right now. Temp drop should slow or even stop overnight. However, the winds are very light and the air still fairly dry with 40-sumpin` dewpoints in the higher elevations and only l-m50s elsewhere. If there is any wind, it will become more southerly by daybreak and will bring in better moisture. The mid clouds overhead in the morning may hold a few sprinkles or very light showers - but the main effect of the clouds will create problems in the forecast for afternoon and evening convection. The thickest patch of the mid clouds should move across the fcst area W-E before breaking up a bit during peak heating. A weak upper shortwave will slide across the region and should allow for cells to grow tall enough to produce thunder. The amount...intensity and location of showers and isolated to sctd TSRA will depend highly on the amount of llvl heating we can achieve through the cloud cover. The highest POPs will be over the Alleghenies. In addition...there still looks like there is a weak mid-level capping inversion in the morning. But, CAPES are progged to get rather fat in the afternoon = 500 to 1100J/kg. The low shear environment will mean there will be little organization to the showers/storms. SPC does not even put us in the marginal risk. High temps should be a few deg F lower than Wednesday for most places due to the cloud cover. The NW mountains may not get to 80 degrees. && .SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/... Precip chances get much lower after sunset, but a few cells may survive until close to mmidnight. Then the light wind overnight could allow for fog to form as the moisture/dewpoints will be much higher than the last few nights - especially after many places will get a little rain on Thursday. While there should be a lull in the showers later tonight and Friday morning, the CAPE gets high in the afternoon - possibly much higher than Thursday. Models generate only scattered convection, though. Will hold the course with 30-40 POPs at this point. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... The large scale pattern has a decidedly summertime look and feel to it through the Memorial Day weekend and into next week with light winds aloft and a prevailing ridge across the northeast CONUS. Temperatures will average above normal with the core of the `hot` weather front-loaded Friday-Sunday before trending modestly toward late May/early June climatology. Precipitation risk early in the period should be characterized by diurnal convection with the highest probs occurring during peak afternoon heating, augmented at times perhaps by weak disturbances drifting through aloft. Max POP may be centered on or around Memorial Day as a weak shortwave suppresses heights as it passes by to the north and some interaction takes place with `tropical` system migrating toward the southeast U.S. coast. Latest NHC forecast says this area of disturbed weather has a 30% chance of cyclone formation in the next 48 hours. && .AVIATION /05Z THURSDAY THROUGH MONDAY/... High pressure will continue to dominate the pattern overnight so expect VFR to continue through mid morning across PA. The low- level flow will become south to southwesterly late Thursday morning and through the afternoon. As the system moves in from the west, there could be a few showers and thunderstorms late Thursday afternoon/Thursday evening. There still is a lack of confidence is how widespread of the showers given the weakening of the the mid and upper wave and its potential to trigger convection. Dewpoints should also be relatively low to begin with and would need to increase substantially for any appreciable convection to form. There is a better chance for scattered afternoon SHRA/TSRA on Friday. OUTLOOK... Fri-Sun...Isold...mainly pm tsra impacts possible. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Dangelo/La Corte NEAR TERM...Dangelo SHORT TERM...Dangelo/Lambert LONG TERM...Steinbugl AVIATION...Lambert/Ceru is the U.S. government's official web portal to all federal, state and local government web resources and services.