Area Forecast Discussion
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FXUS61 KCTP 211052
Area Forecast Discussion
National Weather Service State College PA
652 AM EDT Fri Oct 21 2016
Periods of rain will cover western and central portions of the
state today...while intially dry conditions over the southeast are
replaced by a chance of showers later today. Showers will decrease
tonight...but unsettled conditions will continue into the weekend
with windy and much colder weather expected on Saturday and
Saturday night. The first bout of lake effect and upslope rain
and snow showers will persist into Saturday night...before drying
and improving conditions arrive on Sunday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Significant flooding continues from southern Centre County
through the Lycoming Valley where locally 6 to 7"+ of rain fell in
less than 4 hours overnight. Water rescues have continued through
the pre dawn hours...and there have been reports of rock and
mudslides in Lycoming County and some communities remain under
The heavy training rainfall has come to an end over the flood
area...but additional showers are moving through the area...and
steady rain of lesser intensity will spread east later this
morning and this afternoon and bring an additional half inch to
inch across Lycoming Valley. Steady rain will become more showery
late this afternoon across the west and north.
Expect the heaviest rain today to fall over the west and
north...where Flood Watches remain in effect...and widespread
1-2"+ are expected. Highs will range from the lower 50s northwest
to the mid to upper 70s southeast.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
Cold conveyor belt persists across PA tonight with homogenous
showers spread throughout the commonwealth. POPs will be highest
across the west and north...and lowest across the southeast thanks
to downsloping component.
A cool and unsettled day is in store Saturday as persistent
northwest flow and progressively cooler boundary layer air is
forced into the region. In fact 850 mb temps remain below 0
throughout the day throughout central PA...and we`ll certainly be
looking at a few flurries mixing in with any shower spritzes in
the afternoon and evening over the higher terrain of the northwest
and northern mountains.
Maxes will range from the lower 40s northwest to the lower to
middle 50s southeast.
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Anomalous upper level trough will close off and take on a
negative tilt early in the period, with a deepening coastal
surface low tracking from southern New England north and west into
eastern Quebec. A seasonably cold and brisk northwest flow will
grip the area early this weekend with lake effect and orographic
rain and snow showers likely over the Northwest Mtns and Laurel
Highlands into Saturday night. There is still a low risk for
coating into Saturday night with accums very hard to come by
during the daylight hours this early in the season. 25-35 mph wind
gusts will add an additional blustery chill to below normal temps.
GFS/EC/CMC all show a fast-moving low diving through the Great
Lakes and Northeast into early next week. There is better
agreement with this system embedded in the WNW flow aloft passing
to the north of the area with max POPs over the far northern
tier. This feature will reinforce the cold air aloft at least into
Tuesday before strong warm advection commences through midweek.
The models show a low near the Great Lakes by the end of the
period with some hints a at a cold air damming pattern at low
levels with high pressure retreating into New England. Overall
not much pcpn expected Mon-Wed.
Temperatures will be noticeably colder by the weekend with highs
in the low 40s to mid 50s on Saturday. Expect some moderation on
Sunday followed by a steady to cooling trend with readings
averaging near to below normal through next Wednesday.
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
Adjusted 06Z TAF package for current radar. UNV and IPT
near the back edge of the heavier showers and storms. Another
hour or so for heavy storms.
Next batch of rain later tonight into Friday will be in the
form of more of the way of rain, instead of showers and storms.
Rain could linger into Friday evening, so did not try to end
rain too fast in 06Z TAFS.
The convective type of rain we had so far will give way to
widespread showers and lower ceilings and visibilities later
tonight into Friday, as a cold front moves into the area.
Front will be slow to move east of the area before late Friday.
Sat...Scattered showers with restrictions NW. Brisk NW wind.
Sun...No sig wx.
Mon...Mainly VFR. MVFR with rain showers possible NW.
Tue...No Sig Wx.
Flash Flood Watch until 2 PM EDT this afternoon for PAZ004>006-
NEAR TERM...DeVoir/La Corte/Tyburski
SHORT TERM...DeVoir/La Corte