Area Forecast Discussion
Issued by NWS State College, PA-- Remove Highlighting --
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FXUS61 KCTP 232356
Area Forecast Discussion
National Weather Service State College PA
756 PM EDT Thu Mar 23 2017
High pressure will drift off of the eastern seaboard tonight,
allowing a warm front to lift into the region Friday. Patchy
sleet and freezing rain is expected over central and northern
areas from the early to late morning Friday before precipitation
changes to all rain. The rain front will stall along the New
York border, then oscillate in the vicinity of northern
Pennsylvania through early next week...separating milder air to
the south from cooler air and showers north.
.NEAR TERM /UNTIL 8 AM FRIDAY MORNING/...
Mostly clear skies this evening. But satellite imagery shows the
cloud shield with the warm advection over east-central Ohio and
thicker clouds back over Indiana and very thick clouds over
Wisconsin. So radiational cooling should be quite good through
about midnight. Most areas will fall near or just below 32F
overnight before clouds spread west to east over the region.
All the model guidance implies some light precipitation move
from northwest to southeast over the region. It could rain any
time after about 1 AM in Warren county and as the precipitation
Forecast amounts are very light a few hundreths for most areas.
Showed potential for ice after 3 AM over most of north-central
Guidance shows a quick warm up so in this period any rain could
glaze colder surface and untreated roads.
We have a slight chance of freezing rain in southeastern PA but
think rain will be dominant and very light. So did not cover in
.SHORT TERM /8 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
Any freezing rain should change to rain or drizzle rather
rabidly. Faster in the west where it will warm faster and some
FZRA could linger in eastern/northeastern areas until 10 or 11
AM. Higher QPF amounts in general should be to the north.
Any precipitation after 11 AM everywhere should be rain. Best
chance should be closer to the New York border.
The chance of any precipitation should lower in the afternoon
and we should have a rather quick warm-up. High temperatures
should range mainly from the 50 to the lower 60s. Warmest in the
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
At the outset of the longer term period the models are in fair
agreement in timing and strength. All are indicating a boundary
just to the north of Pennsylvania with a large upper level low
moving through the central midwest. A negatively tilted ridge
over the mid Atlantic will allow for stable but cloudy weather
into Saturday. Lows Friday night into Saturday should range from
the upper 40s to low 50s. There could be light rain showers on
Saturday but warm and stable. A cooler moist boundary should
move into the region Sunday out ahead of the approaching low.
Have adjusted POPs for timing and intensity. QPF remains
variable but possible wet period Sunday into Monday.
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 be markedly cooler behind
a backdoor cold front and a likelihood of rain. However, above
average temperatures (especially nighttime) appear very likely
through early next week, as 12Z GEFS indicates Pa remains
beneath a mean upper level ridge and plume of anomalous PWATs.
The chance of showers will spike with passage of next shortwave
Tuesday into Wednesday.
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
Widespread VFR flying through the period. High to mid level
clouds will increase tonight with surface winds veering to
90-160 degrees. Light precip will likely move across the
airspace between 06-18z Friday, starting as RA/FZRA/PL before
transitioning to all RA by 15z Friday. Added PROB30 group to
hedge toward brief period of ice mix around daybreak Friday.
Fri...VFR/MVFR. Pcpn ending after 18z.
Sat...Mainly VFR. Chance of rain northern 1/2 airspace.
Sun-Tue...Sub-VFR with periods of rain.
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
Winter Weather Advisory from 4 AM to 11 AM EDT Friday for