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fxus61 kctp 221534 
afdctp

Area forecast discussion
National Weather Service State College PA
1034 am EST Wed Feb 22 2017

Synopsis...
an extended period of very mild weather with temperatures
nearing or exceeding record levels in many locations will
continue today through Friday. A strong cold front is expected
to bring a few periods of showers and thunderstorms on Saturday.
Gusty westerly winds, colder temperatures, and snow showers
across the western mountains will follow the frontal passage
for later Saturday into early Sunday.

&&

Near term /until 7 PM this evening/...
a few sprinkles making it to the sfc around the central slice of
zones, and a cluster of showers is moving into the northwest as well.
The mid deck making the sprinkles is moving to the east, and the
hrrr/rap diminish coverage of the northwest showers. But, clouds are
still going to be tough to get rid of totally, esp in the northwest
half of the area. This will likely serve to keep temps down a
deg or two from going maxes. Will nudge them downward just a bit
but remain optimistic for 60s in many locations as kduj/kjst
both already into the m50s.

Prev...
early morning infrared satl loop and regional radar mosaic continues
to show plenty of high based strato cu and Alto cu clouds spread
across the entire County Warning Area.

Nothing more than some scattered sprinkles (or perhaps a brief
rain shower) was noted on radar and sfc ob sites early this
morning, and that will continue to be the case for much of the
day today as a weak, washed-out frontal boundary lingers across
northern PA or southern New York.

We have yet another very mild early morning with temperatures
averaging 15-20 deg above normal. Low temps around sunrise will
vary from the upper 30s in parts of northern and eastern PA,
with mid and upper 40s occurring at many other locations.

A fairly thick mid cloud deck will blanket the forecast area
through the late morning or early afternoon hours today,followed
by some intervals of sunshine mixing with the patchy altocu and
lingering cirrus cloud deck.

Considering the mild start to the day, and gefs mean 850 mb
temps of 7-8c, we should see Max temps easily reaching the upper
50s to lower 60s across the north, and generally mid 60s
throughout the southern half of the state.

&&

Short term /7 PM this evening through 6 PM Thursday/...
periods of high clouds and a light southerly breeze tonight will
help to keep temps on the mild side, with temps a few to svrl
deg f warmer than early Wednesday.

Perhaps the warmest day of the late week period will occur
Thursday as the mean boundary layer flow veers around to the SW
and is accompanied by periods of sunshine.

Consensus of all model guidance suggests just a slight chc of an
afternoon shower (or even some isolated brief tsras), thanks to
roughly 500-1000 j/kg of sfc-based cape on average across the
region.

Afternoon high temps Thursday will be near, or a few deg f above
records for Feb 23rd. Maxes will be in the lower-mid 60s north
of the I-80 corridor, and in the upper 60s to lower 70s across
the southern half of the state.

&&

Long term /Thursday night through Tuesday/...
very mild temperatures will persist for the end of the week,
likely reaching records levels at least in some locations once
again Friday afternoon.



The overall, large-scale pattern becomes more amplified late in
the week as a system over the Central Plains deepens and lifts
into the Great Lakes. Clouds will increase late Thursday and
Friday with warm front lifting through, and bringing increasing
rain chances heading into the weekend, followed by a shot of
colder/windy conditions Saturday through Sunday.

&&

Aviation /15z Wednesday through Sunday/...
have started to mention -shra in kbfd for the next few hours as
showers to the west look to be making good progress ewrd. The
cigs are already expected to dip to MVFR. The coverage is
likely to break up per latest hrrr/rap guidance, but just can't
ignore the trend and proximity of current activity.

Prev...
the flight category will remain predominantly VFR across
central PA airspace into tonight with ceilings ranging between
5-10kft. MVFR cigs are possible across the northwest 1/3 of the
airspace with a few rain showers. Coverage of -shra is too
sparse/limited to include in tafs. Trouble spots tonight into
Thursday look to be the northwest and southeast portions of the airspace with
potential for IFR low clouds (nw) and fog/reduced visibility
(se).

Outlook...

Thu-Fri...sub-VFR restrictions possible early. Chance of rain
mainly northwest 1/2.

Sat...llws. Strong frontal passage with sub-VFR likely in moderate rain
showers. Isolated ts psbl. Post-frontal wind gusts 25-35kts from
260-300 degrees psbl with snow showers northwest 1/3 Saturday night
into early Sunday.

Sun...sub-VFR northwest 1/3 with scattered snow showers. Gusty winds
from 300 degrees.

&&

Climate...
***february warmth 2017*** updated 2/22/17 at 8am EST

Record high temperatures for select sites from Feb. 22-24:
----------------------------------------------------------

Harrisburg 2/22: 71 in 1974
Harrisburg 2/23: 70 in 1985
Harrisburg 2/24: 75 in 1985

Williamsport 2/22: 66 in 1974
Williamsport 2/23: 70 in 1985
Williamsport 2/24: 71 in 1985

Altoona 2/22: 62 in 1974
Altoona 2/23: 66 in 1977
Altoona 2/24: 69 in 1985

Bradford 2/22: 57 in 1975
Bradford 2/23: 57 in 1977
Bradford 2/24: 59 in 1961

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

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

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
near term...dangelo/Lambert

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