Area Forecast Discussion
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FXUS61 KCTP 260540
Area Forecast Discussion
National Weather Service State College PA
140 AM EDT THU MAY 26 2016
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
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
.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
.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.
Fri-Sun...Isold...mainly pm tsra impacts possible.