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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 241005
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
605 AM EDT Mon Jul 24 2017

.SYNOPSIS...
An upper trough, located over the Great Lakes early this
morning, will push slowly across Pennsylvania early this week.
In its wake, high pressure will build southeast across the
region by midweek. A cold front will likely push southeast
across the region next Friday.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
-- Changed Discussion --
Radar trends at 10Z showing back edge of steady rain beginning
to lift out of eastern Pa, as weak surface low over the Delmarva
Peninsula and associated southeasterly low level jet lift out.
Latest HRRR runs and upstream conditions suggest the steady
rain will exit the eastern portion of the forecast area by
around 12Z. Earlier flooding concerns have diminished and
remaining stratiform rain over the northeast part of the
forecast area is not anticipated to cause more than minor
flooding early this morning.
-- End Changed Discussion --

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 AM TUESDAY/...
-- Changed Discussion --
Upper trough over the Grt Lks is poised to swing into the
region later today, causing scattered convection to break out
along and ahead of associated cold front as early as mid
morning over the northwest mountains, and mainly during the
afternoon elsewhere.

After a cloudy start to the day in many locations, model
soundings indicate a fair amount of sunshine developing by
midday, as lower PWAT air filters in on westerly flow. NCAR
ensemble indicating prefrontal CAPEs rising to around 1000 J/KG
by afternoon across the eastern 2/3rds of the forecast area.
The combination of modest CAPEs and 0-6km shear of 40-45kts will
support a marginal threat of severe weather during the
afternoon. Convection-allowing models indicate the best chance
of showers will come during late morning/early afternoon across
the northwest mountains, with more robust convection forming
along cold front, as it pushes through the rest of the forecast
area during the afternoon hours.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Not a lot of change from yesterday. Still going mainly
with dry conditions Tuesday into Wed. Did lower temperatures
a degree or so on Tue, given concern for some clouds and
lack of real strong cool push. Also models show pair of weak
lows just inland from the south shore of the lower Great
Lakes, not sure what to make of this. A strange summer lately.

Still expecting showers and storms on Thursday into the first
part of Friday, with the next cold front.

Went with mainly dry conditions after early Friday.

&&

.AVIATION /10Z MONDAY THROUGH FRIDAY/...
Heaviest showers (now with very mininal lightning) now contained
to along and east of the Susq River at 10Z, and will continue
to impact IPT-MDT-LNS through ~12-13z. West of there,
conditions somewhat variable from location to location, but
generally MVFR over the central mtns and IFR over the
western/northern mtns - which will persist into the mid morning
hours before improvement (lasting the longest in the NW Mtns).

An upper trough will push slowly across Pennsylvania today and
Tue. This will kick off another round of showers and
scattered thunderstorms this afternoon with intermittant
localized impacts.

Showers diminish by evening, but linger the longest in the
northern mtns. This is also the best chance for ceiling
restrictions tonight. With plenty of low level moisture around,
expect valley fog to develop areawide as well.

.OUTLOOK...

Tue-Wed...AM cig restrictions north/west. Valley fog areawise.
Otherwise no sig wx.

Thu-Fri...Chance of afternoon TSRA/SHRA.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch until 8 AM EDT this morning for PAZ041-042-
046-049>053-058.

&&

$$
SYNOPSIS...Fitzgerald
NEAR TERM...Fitzgerald
SHORT TERM...DeVoir/Fitzgerald
LONG TERM...Martin
AVIATION...RXR