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fxus61 kctp 230616 
afdctp

Area forecast discussion
National Weather Service State College PA
216 am EDT Thu Mar 23 2017

Synopsis...
one really cold night tonight before a more seasonable Spring
pattern returns. The temperatures will rise back to near or
above normal levels through the end of March. A wintry mix
remains possible early Friday morning before changing to rain.
The weekend starts off very mild with rain likely by Sunday, and
continued chances for showers early next week.

&&

Near term /until 7 am this morning/...
a light breeze still noted across the area at 05z, acting to
hold the temps up a bit. Still think winds will become calm by
dawn, as high pressure becomes centered directly over central PA
and skies remain clear. The anomalously dry air, coupled with
clear skies and a calm wind, will result in near record lows.
See the climate section for 3/23 minimum temperatures records.
Expect mins to range from the single digits across the northern
mountains, to the teens across most of central PA and around
20f in the urban centers of the lower susq valley.

&&

Short term /7 am this morning through 6 PM Friday/...
after a cold start, temperatures will begin to rebound as the
surface high passes east of PA and a return southerly flow
develops. Highs today will still be below average but it should
feel noticeably warmer with very light surface winds and plenty
of late March sunshine bringing peak temps in the 40s over much
of the area. The higher terrain of northeast PA, where snow
still covers the ground, will likely not make it out of the 30s.

&&

Long term /Friday night through Wednesday/...
warm air advection pattern ramps up quickly Thursday night into Friday via
anomalous west-southwest low level jet. Model solutions all keep
on with temperature profiles/low-level temps favorable for
freezing rain. The cold air might be deep enough for a little
sleet at first, but just enough to mention. Will keep the
p-type to r or freezing rain after sunrise over the NE. As we are finding
today, the heat from the late March sun does wonder. But, there
is still snow on the higher elevation, esp in the NE where the
threat for freezing rain is higher. Will keep on with mentions of just a
few hundreths of ice for now. Overall impact appears minimal
but it only takes a small amount of ice to cause problems
especially during the early morning commute. Temps should climb
above freezing everywhere by mid morning Friday ending the risk
for ice.

Rain focus should shift north into New York Friday afternoon into
Friday night as baroclinic zones sets up in upper level
confluence zone downstream of deep cyclone moving through the
Southern Plains. The boundary placement will be key to the fcst
but it looks for now that most of the area will be in the mild
warm sector.

The models and ensembles continue to show a series of upper
troughs progressing onshore from the eastern Pacific and across
the southwest/south-Central Plains before deamplifying as they
move east of the MS river. The first of 3 upper troughs emerges
from the Southern Plains and crosses into the MS valley Sunday
and continues to weaken as surface frontal wave translates
downstream crossing the Ohio Valley/Great Lakes into the northern
mid Atlantic states by Monday. Blend of nbm/ecens/wpc still
indicating Max pops in the Sunday-Sunday timeframe.

Above average temperatures are expected over the weekend with
the warmest day likely on Saturday with some sites approaching
70f over southern PA. Sunday should also be mild but a bit
cooler due to the likelihood of rain. Fcst issues pertaining to
a backdoor cold front appear to be confined to New England early
next week with temperatures remaining near or or above climate
averages into early next week.

&&

Aviation /06z Thursday through Monday/...
widespread VFR flying through the period. High to mid level
clouds will gradually increase with surface winds veering to
90-160 degrees tonight into early Friday. Light precip will
likely move across the airspace between 06-18z Friday, starting
as rain/fzra/pl before transitioning to all rain by 15z Friday.

Outlook...

Fri...VFR/MVFR. Pcpn ending after 18z.

Sat...mainly VFR. Chance of rain northern 1/2 airspace.

Sun-Mon...sub-VFR with periods of rain.

&&

Climate...
minimum temperature records for 3/23 at select sites:

Mdt: 14 in 1934
ipt: 8 in 1906
bfd: 5 in 1959
aoo: 15 in 1960

&&

Ctp watches/warnings/advisories...
none.

&&

$$
Synopsis...rxr/steinbugl
near term...Fitzgerald

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