Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 250130
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
830 PM EST Fri Feb 24 2017

.SYNOPSIS...
A strong cold front will plow east across the region on Saturday
and create 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 Saturday and Sunday in 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 MIDNIGHT TONIGHT/...
Unseasonably warm conditions for mid to late February with
evening temps some 30+ degrees above normal. All-time February
record highs set at both Williamsport (76F) and State College
(PSU weather center - 74F). Balmy southerly wind will continue
throughout the evening.

&&

.SHORT TERM /MIDNIGHT THROUGH 6 PM SATURDAY/...
Takeaways: CFROPA expected around 12Z W and 18Z E. SHRA/TSRA
along and behind the front. Some will be strong/gusty. Severe
not out of the question, but risk still only MRGL in newest DY2
outlook from SPC. Gusty post-front but not wind advy-worthy.

Overnight: The SSE flow up into the mountains will lead to low
clouds and they may get thick enough to produce some drizzle or
even very light showers overnight. The faster the clouds thicken
up, the warmer it will stay overnight. Will run with mins in the
50s. (Yes, it just seems plain bizarre writing that in late
Feb.)

The clouds will also make it tough to destabilize during the
morning - esp in the NE where the --precip may be lingering
into the first part of the day. The front will push across
steadily and only taking about 6 hours to cross the entire CWA.
POPs will be pegged at 100s.

Temps will drop very quickly and should be back into the L-M30s
in the NW by the end of the aftn. SHRA 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 /SATURDAY NIGHT THROUGH FRIDAY/...
The mid range models all have similar timing for FROPA. 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 NW mtns.

After some morning flurries and scattered snow showers in the
NW 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 /01Z SATURDAY THROUGH WEDNESDAY/...
Widespread VFR conditions noted across central Pa at 00Z, which
will remain the case into the late evening hours. An
increasingly moist south-southeast flow is expected to result in
developing stratus across eastern Pa late tonight. Believe
current LAMP guidance is a bit too pessimistic regarding CIGs
late tonight. Although pattern favors IFR CIGs over the higher
terrain of eastern Pa late tonight, not so sure about the lower
elevation airfields, including KIPT, KMDT and KLNS. If IFR were
to develop in those location, favor the idea of it taking until
around dawn to occur, as the latest HRRR depicts.

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 CIGS possible.

&&

.CLIMATE...
***February Warmth 2017*** Updated 2/24/17 at 5 am EST

Record high temperatures for select sites for Feb. 23-24:
----------------------------------------------------------

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...Dangelo/Lambert
NEAR TERM...Dangelo/DeVoir
SHORT TERM...Dangelo
LONG TERM...Ceru/Gartner
AVIATION...Fitzgerald
CLIMATE...



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