National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 281848
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
248 PM EDT Wed Jun 28 2017

.SYNOPSIS...
High pressure will move off the eastern seaboard later today
setting up a warmer and more humid airflow beginning on
Thursday. A cold front on Saturday will bring a brief break in
the humidity.

&&

.NEAR TERM /THROUGH TONIGHT/...
Current observations continue to indicate partly to mostly
sunny skies across the region with sfc high pressure centered
over the Middle Atlantic states. Thicker cu field is noted over
the northern half of central PA. Regardless, no pcpn is expected
today with high temperatures mainly in the 70s.

IR satellite imagery shows wide north to south oriented bands
of cirrus moving into western PA ahead of convection over Great
Lakes region. This will spread east through the evening hours
with little expected affect on sensible weather.

The surface high will move east of the area tonight with
another comfortable sleeping night in store with dewpoints
still only in the 50s.

&&

.SHORT TERM /THURSDAY/...
By Thursday the eastern US will be under a broad upper ridge,
but close to the southern edge of the main westerlies. A warmer
and more humid airmass will begin to advect into the region
between the offshore high and a low moving north of the Gr
Lakes. Deterministic models develop a fair amount of CAPE and
mid level lapse rates are forecast in the 6-7C/km range, so an
afternoon shower or thunderstorm is likely in a few spots. SPC
Day 2 convective outlook has northwestern third of CWA in a
marginal risk for severe and remainder of CWA in general
thunder. Coverage looks to be isolated to scattered at best and
will likely be in the mid afternoon into the evening hours.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
The upper pattern starts out with the broad ridge and high
heights over the eastern US, before eventually becoming more
broadly cyclonic, but still with heights remaining seasonably
high as most shortwave energy slides through southern Canada.

Friday will be warm and humid with diurnally driven
showers/storms possible. The deterministic ECMWF/GFS both show
the mid levels being relatively warm suggesting coverage will
be on the scattered side.

A cold front is progged to be entering the region Saturday and
moving east of the CWA early Sunday, so we should see a better
chance of more widespread rain. The front is expected to be
weak, so temperatures behind it will not change much, just a
bit of a break in the humidity for the second half of the
weekend.

Sunday Night into early Tuesday look mainly dry as high pressure
builds over the region. The cold front will begin sliding back
north as a warm front Tuesday into mid week, bringing renewed
humidity and increased chances for the usual summertime showers
and thunderstorms.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
High pressure building into the area from the Ohio Valley will
supply mainly VFR conditions and light wind today through
tonight and into Thursday morning. Localized vis restrictions
from fog will possible again Thursday morning but should be less
widespread than this morning.


.OUTLOOK...

Thu-Fri...Isolated PM tsra impacts poss, mainly northern Pa.

Sat...Scattered PM tsra impacts possible.

Sun-Mon...No sig wx expected.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...Gartner
NEAR TERM...Gartner
SHORT TERM...La Corte/Gartner
LONG TERM...La Corte
AVIATION...Gartner