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fxus61 kctp 251602 

Area forecast discussion
National Weather Service State College PA
1102 am EST Sat Feb 25 2017

a line of thunderstorms capable of damaging winds are forecast
this afternoon across east-central Pennsylvania. Gusty winds
and noticeably colder temperatures will follow behind a cold
front later today into tonight with scattered snow showers
across the alleghenies.


Near term /until 6 PM this evening/...
line of moderate showers with a few embedded thunderstorms/ltg
moving quickly east across the alleghenies into the Central
Ridge/valley region. Temperatures have likely reached their Max
west of a line from Wellsboro to State College to Bedford. 15z
Storm Prediction Center mesoanalysis shows a pocket of 500 j/kg of MLCAPE starting
to develop over the lower susq. Valley where temps should peak
around 70f around midday-early afternoon.

Strong forcing along cold front moving into high shear/Low Cape
environment over the eastern 1/2 to 1/3 of the County Warning Area should
support solid/intensifying line of convection. Cams show the
evolution of a strongly-forced squall line rather well, moving
quickly east with peak timing/intensity fcst between 17 and 21
UTC. The line should exit the County Warning Area after 21z with risk for severe
storms/damaging winds ending this evening.


Short term /6 PM this evening through 6 PM Sunday/...
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.

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.


Long term /Sunday night through Friday/...
the latest 00z oper and efs runs show a warm frontal boundary
moving into the region Tuesday. This will bring the next chance
for light 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 /15z Saturday through Wednesday/...
25/15z| line of moderate showers with embedded thunderstorms
moving across the western 1/2 of the airspace this morning. The
line is expected to intensify over zny sector with risk for
strong to locally damaging winds (40+kt) impacting the eastern
1/2 of the airspace 17-21z. Gusty winds (25-35kt) expected
behind cold front with wind shift to 250-300 degrees by this
evening. Expect shower activity to taper off behind the front
from west to east behind the front later this afternoon into the
evening. Colder air will filter into the area with scattered
light snow showers developing downwind of Lake Erie and across
the higher terrain of western PA with some lower cigs and brief
visby reductions psbl into Sunday.


Sun...MVFR/-shsn west bcmg VFR. Mainly VFR central-east.
Decreasing winds.

Mon...mainly VFR. Chance of rain.

Tue-Wed...rain showers/reductions likely.


**updated 11am 2/25/17**

New record high temperatures for Feb. 24:

Harrisburg 2/24: 76. Previous 75 in 1985; all-time Feb record
is 78f.

Williamsport 2/24: 76. Previous 71 in 1985; new record high
temperature for the month of February.

Altoona 2/24: 75. Previous 69 in 1985; new record high
temperature for the month of February.

Bradford 2/24: 69. Previous 59 in 1961; new record high
temperature for the month of February.

State College 2/25: 74. New record high temperature for February
and meteorological winter (djf).


Warmest February on record (avg. Temperature through 2/24)

Harrisburg: 2017 rank=1 (40.8)
2. 40.4 in 1998
3. 39.6 in 1976
4. 39.4 in 1954

Williamsport: 2017 rank=1 (37.6)
2. 37.0 in 1998
3. 36.1 in 1954
4. 35.6 in 2002

Altoona: 2017 rank=1 (39.3)
2. 37.4 in 1976
3. 36.2 in 1998
4. 35.9 in 1990/1954

Bradford: 2017 rank=t1 (32.3)
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...


near term...Lambert/steinbugl

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