Area Forecast Discussion
Issued by NWS State College, PA-- Remove Highlighting --
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FXUS61 KCTP 300021
Area Forecast Discussion
National Weather Service State College PA
721 PM EST Tue Nov 29 2016
A wave of low pressure will ride northward from the Tennessee
valley and move through the state on Wednesday. Another widespread
rain will occur and will be followed by much colder air for the
second half of the week. The northwest flow after the storm passes
will generate some lake effect rain and snow showers for the
latter half of the week.
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Remnant showers slipping away from eastern Lancaster County early
this evening. The damp ground and high ambient moisture combined
with the winds going calm again will probably result in areas of
fog forming this evening and overnight. Normally, the still air
and some clearing would be good for radiational cooling, but the
40-50F dewpoints will keep it from getting too cool overnight.
Wide-reaching storm over the central and eastern CONUS will re-
load with Gulf moisture overnight. A triple point low begins to
form over the Ohio valley tonight as the heights fall over the
Great Lakes and eventually over the eastern states on Wed.
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Sfc low lifts up the old front and bubbles up to meet the OH vly
low on Wednesday...resulting in widespread rain and perhaps even
a thunderstorm along the MD border. However, the prob for T is
very low, and will leave out of the wx grids for now. QPF still in
the 0.5-1.00" range for Wed. The cold air will finally push
into/across the region on Wed afternoon and evening.
Wed night will be a return to November. Colder northwest flow will
help generate some lake effect showers. It really won`t be cold
enough in the cloud layer for snow until the very end of the
short term period. Will not mention any accums since temps in the
NW won`t even get to/below freezing by Thurs morning.
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Low pressure area lifts over New England and then off the East
Coast, setting the stage for an extended period of breezy west-
northwest flow. The upstream airmass won`t be especially cold
(still no "wintery" cold air to be found, so temperatures will
drop but only to near or just below seasonal normals. But that
air flowing over the still quite warm lakes will be enough to
provide an extended period of widespread cloudiness and frequent
lake enhanced snow / rain showers over the the NW mountains down
into the Laurel Highlands, possibly lasting all weekend as several
weak ill-timed waves ripple through the upper flow.
Longer-range models finally compromising on a solution starting
early next week, with the EC storm receeding from the map. Looks
like Monday will bring ridging and rebounding temps to Central PA.
A weaker storm system begins to get organized coming off the
southern Rockies, with initial impacts for us being potential for
a difficult to time wave to run out ahead in the SW flow. This
will keep mention of chance rain in the forecast for Tue. More
interested feature we`ll have to keep an eye on after that will be
sharpening of the big trough/deepening of a surface low over the
midwest next midweek, with Central PA sitting on the warm side.
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --00Z TAFS sent.
Western areas that had some clearing earlier, now have some dense
fog at times. This will be the case overnight.
Further east, IFR conditions will prevail with low ceilings.
Not expecting much in the rain prior to Wednesday morning.
LLWS in for BFD, given that the wind fields will be stronger
there late tonight and on Wed.
While conditions may improve at times on Wed, expect some
showers and rain at times. Perhaps a thunderstorm late with
the cold front, given the strong wind fields and rather high
dewpoints for this time of year.
Some snow and rain showers across the far west and north late
Wednesday night into Friday, as colder air works into the area
behind the cold front.
Thu-Sat...Sct SHSN w/ocnl IFR in BFD-JST. Isold SHRASN AOO-UNV-
IPT. VFR SE.
Sun...Mainly VFR. Restrictions still poss NW in the morning.
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LONG TERM...La Corte/RXR