Area Forecast Discussion
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FXUS61 KCTP 221020
Area Forecast Discussion
National Weather Service State College PA
620 AM EDT SUN MAY 22 2016
A slow moving storm system will keep it cool and unsettled into
Monday. A ridge of high pressure will make a return to the eastern
U.S. ushering warmer and eventually more humid conditions from mid
week into the upcoming holiday weekend.
.NEAR TERM /THROUGH TONIGHT/...
Water vapor loop shows a well-defined circulation over Pa. Slow
moving rain bands fit nicely under model diagnosed low-mid level
frontogenetic forcing as the upper trough continues to deepen
Heights are forecast to continue lowering with the upper low made
to close off this morning into the afternoon over central or
southern Pa. It all points to continued cloudy-cool conditions with
periods of rain and drizzle, improving later today from the north
as the low drops due south into Va by evening.
If we can manage any sunshine later today, mainly over
northwestern areas, there could be a low topped thunderstorm
given the cold air aloft and expectations of steepening mid level
lapse rates on this northern and western edge of the deepest
Another cool day in the 50s to lower 60s will continue the trend
of a cold and wet May. We may be able to eat away at the below
normal numbers by mid to late week, but so far it has not been a
very nice May, the first month of what many consider the start of
the traditional warm season.
As the upper low heads toward bottoming out near Cape Hatteras
late tonight and Monday morning, drier conditions will develop
with the increasing distance from the main forcing mechanism. The
best chance of rain will be early in the evening and over southern
areas, with the chances diminishing the deeper into the overnight
Lows will average in the upper 40s to lower 50s where it stays
cloudy. The far north will dip into the low to mid 40s under
.SHORT TERM /MONDAY/...
The growing expanse of the upper level cyclonic flow will help
support weak large scale ascent. This along with cold air aloft
will help erode stability during the time of max heating with
model derived mid level lapse rates on the order of 6-7C/km. It
will equate to showers and scattered thunderstorms becoming more
numerous in the late morning and afternoon hours.
Highs Monday will rebound into the 70s which will still be a
little below normal in many areas, but definitely better than we
have been experiencing the last couple of days.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
The extended is advertising the development of a western trough
and an eastern ridge by the middle of the upcoming week, finally
signaling the arrival of summer-like temperatures and like it or
Evolution of the slowly filling and lifting out upper low will be
the focus early in the period and will keep the mention of a
shower possible over eastern areas even into Tuesday. But by mid
week the low will have given way to the first real surge in the
subtropical ridge of the season with the NAEFS advertising above
normal heights and temperatures from Wednesday right through the
Memorial Day weekend.
The broad wsw flow will also mean that remnant convection from
Midwestern MCS activity will become a threat as it slides toward
the nern U.S.. Timing at this range is impossible, but I`d expect
the activity to be mainly diurnally driven, tending to fade during
the evening and overnight.
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
Complex low pressure system dropping southward today
will keep cloudy and wet conditions across the area.
Looking at mainly mvfr and ifr conditions. As been
the case overnight...a wide range of conditions will
09Z TAFS sent.
Some improvement expected for Monday into Tuesday.
Mon...VFR/MVFR with sct showers with isold P.M. tsra impacts
possible ern 1/2.
Tue-Wed...VFR/No sig wx expected.
Thu...Slight chance of P.M. showers/tstms wrn 1/2.
NEAR TERM...La Corte
SHORT TERM...La Corte
LONG TERM...La Corte