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fxus61 kctp 250658 
afdctp

Area forecast discussion
National Weather Service State College PA
158 am EST Sat Feb 25 2017

Synopsis...
a strong cold front will plow east across the region today
accompanied by a few bands of showers and perhaps a narrow line
of strong, gusty thunderstorms. Gusty westerly winds and colder
temperatures will follow the frontal passage. Some snow showers
are also expected late today, tonight and Sunday across the
western Highlands. High pressure builds in from the Ohio Valley
for Sunday but weak waves of low pressure will move up the Ohio
River valley Monday into Tuesday may bring some mixed
precipitation to the northern half of the area, and mainly rain
in the south.

&&

Near term /until 8 am this morning/...
incredibly mild early morning temps for late February (in the
upper 50s to low 60s) running some 30+ degrees above normal.

All-time February record highs were set at both Williamsport
(76f) and State College (psu weather center - 74f) on Friday.
Balmy southerly wind will continue prior to a strong cold
frontal passage (during the mid to late morning hours across the
western third of the state).

Weakened squall line just ahead of the cold front has been
making steady eastward progress overnight, and is pushing to
near the PA/Ohio border at 0630z. Numerous lightning strikes
continue with embedded clusters of thunderstorms and rain within the approx 75
miles wide band of MDT to briefly heavy rain showers over eastern Ohio
and far northwestern PA.

This line should continue to slowly track across Warren County
between 07-0830z, and through Elk and McKean counties between
0830-10z. It will also slowly weaken overnight due to waning
cape. But sct, embedded low-topped thunderstorms and rain with g30-40kt will
survive. Min temps will only reach the mid to upper 50s, except
for the far west, where readings should slide into at least the
l50s by 12z.

&&

Short term /8 am this morning through 6 PM Sunday/...
takeaways: cfropa expected around 12z across the region near and
just to the east of the rt 219 corridor, 14-18z across the
central mtns, and 18z-21z across the eastern part of the County Warning Area.

Storm Prediction Center has the eastern half of PA in a slight risk for today with a
marginal risk for svr extending back to the far northwest part of the County Warning Area
associated with the early to mid- morning convection. Confidence
is increasing for several hundred j/kg of cape (and as much as
pockets of 750 j/kg) fueling a ncfrb that will intensify and
solidify across the central mtns and susq valley during the late
morning and early afternoon. This line will be capable of
tapping and mixing down to the sfc 50kt west-southwest winds that are
present around 5 kft above ground level on model forecast soundings at regional
gridpoints.

Gusty west wind are anticpated Post-cold-frontal, but not Wind
Advisory worthy.

Widespread cloudiness will hinder destabilization during the
morning - esp in the NE where some light showers or local
drizzle may be found during the first part of the day. The
front will push across steadily and only taking about 6 hours to
cross the entire County Warning Area. Pops will be pegged at 100s.

Temps will drop very quickly and should be back into the l-m30s
in the northwest by the end of the aftn. Rain showers will turn to shsn there
in the aftn. Winds will be gusting into the 30s with some peaks
in the 40s behind the front. But, at this point, it does not
look like a wind advy is necessary.

&&

Long term /Sunday night through Friday/...
the mid range models all have similar timing for frontal passage. The
front should be east of central PA by 00z Saturday. Cold
northwesterly flow could allow for snow showers Saturday night
into Sunday. However lack of moisture will only bring light
accumulations with the highest amounts in the northwest mtns.

After some morning flurries and scattered snow showers in the
northwest Sunday, the trough will continue its eastward trek and a more
zonal pattern will overtake the region. This will bring more
tranquil conditions with some sunshine expected for Sunday
afternoon, along with decreasing winds.
However, Max temperatures on Sunday will be back to near
normal. Heights are forecast to rebuild across the eastern
half of the conus early next week on broad southwesterly flow
ahead of troffing developing over The Rockies.
The latest 12z runs show a warm frontal boundary moving into
the region Tuesday. This will bring the next chance for
precipitation with possible warmer than normal temperatures
though not as high as currently. Another upper level trough
moving through the Great Lakes could bring another cold front
through the mid Atlantic region later next week. There are
inconsistencies in timing and placement.

&&

Aviation /07z Saturday through Wednesday/...
some low clouds at lns.

Airmass is still quite dry to the west of the far east, and
there is a brisk wind. Thus not expecting low clouds to advect
too far to the west early this morning.

06z tafs sent.

Earlier discussion below.

11-3.9u loop showing developing stratus across southeast PA at
03z in response to an increasingly moist south-southeast flow.
Based on latest glamp/hrrr meld data, believe odds now favor a
period of IFR cigs at lns running roughly from 07z-15z.
Elsewhere, will maintain the idea of low MVFR stratus developing
across the rest of eastern PA overnight. Although wouldn't rule
out a period of IFR cigs at ipt/MDT early Sat morning.

A strong cold front will sweep eastward across central PA
between 15z-21z, accompanied by a band of showers and possible
thunderstorms. Model soundings continue to suggest the potential
of borderline IFR cigs across eastern PA (mainly MDT/lns) early
in the day. However, by midday the focus will be on line of
showers/tsra accompanying the front, as it pushes across the
state. Brief IFR conditions are possible with this band of
showers and possible tsra. A much drier westerly flow behind the
front should result in a return to VFR conditions late in the
day across most of central PA, while MVFR cigs linger at
jst/bfd.

Gusty west winds will become a concern in the wake of
the front late Saturday, especially in the vicinity of jst/aoo,
where BUFKIT soundings support gusts between 30-35kts. Another
concern will be developing lake effect snow showers Sat evening
at jst/bfd, where tempo IFR visibilities appear possible.

Outlook...

Sun-Mon...no sig wx expected.

Tue-Wed...rain showers/reduced ceilings possible.

&&

Climate...
***february warmth 2017*** updated 2/25/17 at 1 am EST

Records were broken at both Williamsport and Harrisburg
on Friday.

High at Williamsport at 76 degrees at 337 PM.

High at Harrisburg at 76 degrees at 241 PM.

Also records at Bradford, Altoona, and Johnstown.

High at Johnstown 72 degrees at 357 PM.

High at Bradford 69 degrees at 503 PM.

High at Altoona 75 degrees at 322 PM.

Previous information below.

Record high temperatures for select sites for Feb. 24:
----------------------------------------------------------

Harrisburg 2/24: 75 in 1985; all-time Feb record is 78f

Williamsport 2/24: 71 in 1985; all-time Feb record is also 71f

Altoona 2/24: 69 in 1985; all-time Feb record is 74f

Bradford 2/24: 59 in 1961; all-time Feb record is 64f

-----------------------------------------------------------

Most 60 degree days in February at Harrisburg. Based on the
latest forecast, add 4 more days to the list and finish tied
for second with 7 days.

1. 10 days in 1976
2. 7 days in 1930
3. 5 days in 1991, 1943
5. 4 days in 1997, 1985, 1954, 1939
9. 3 days in 2017, 2016, 1996, 1990, 1961, 1932, 1890

------------------------------------------------------------

Warmest February on record (avg. Temperature through 2/21)

Harrisburg: 2017 rank=4 (38.6)
1. 40.4 in 1998
2. 39.6 in 1976
3. 39.4 in 1954

Williamsport: 2017 rank=4 (35.4)
1. 37.0 in 1998
2. 36.1 in 1954
3. 35.6 in 2002

Altoona: 2017 rank=2 (36.5)
1. 37.4 in 1976
evening cooling will be a little slower than last
night.

Bradford: 2017 rank=6 (29.3)
1. 32.3 in 1998
2. 30.1 in 2002
3. 29.6 in 2012
4. 29.5 in 1990/1976
-------------------------------------------------------------

&&

Ctp watches/warnings/advisories...
none.

&&

$$
Synopsis...Lambert

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