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000
FXUS61 KCTP 212331
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
731 PM EDT Sun Apr 21 2024

.SYNOPSIS...
An upper level trough over Pennsylvania will lift out of the
region early this week. A cold front will push across the state
Wednesday morning, then Canadian High Pressure will build into
the region Thursday and Friday. A warm front is likely to push
into the area next weekend.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Early evening satellite loop is showing breaks developing in
the stratocu. Expect this trend to continue with mainly clear
skies after sunset, as the boundary layer cools and the core of
coldest air aloft shifts out of the area.

Clear skies, a diminishing wind and anomalously dry air will set
the stage for efficient radiational cooling tonight, with low
temps close to 10 degrees below average. Daybreak readings
should range from the mid 20s in the normally colder northern
valleys, to the low and mid 30s across the Lower Susq Valley. A
Freeze Warning remains up for the Ridge and Valley Region and
Middle Susq Valley, while a Frost Advisory has been posted for
the Lower Susq Valley.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Rising heights are progged over PA Monday, as surface ridge
builds over the state, resulting in fair and milder weather with
relatively light winds. Model soundings support abundant
sunshine and mixing to 800mb, where temps around -4C translate
to highs ranging from the low to mid 50s over the N Mtns, to
the low 60s in the Susq Valley. A northwest flow and very dry
air above a weak inversion also supports undercutting NBM
dewpoints. We have leaned heavily toward the much lower numbers
obtained from the MixedDewpoint Tool.

Conditions remain favorable for radiational cooling Monday
night, with surface ridging/dry air lingering over the state.
Have therefore blended the lower MAV min temps with those of the
NBM. Expect areas of frost with low temps in the low to mid 30s
over most of Central PA. Clear skies early Monday night will be
followed by increasing (but mainly thin) cirrus late Monday
night.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Tuesday will feature milder temperatures. Models still agree
on timing of showers around 00Z Wed.

Some variation in the amt of phasing of cold fronts later Wed.
Either way, very cold air over Hudson Bay not that far away.
A hard freeze possible across the north and west Wednesday
night and again for Thursday night. While Thursday night might
be a few degrees warmer, lighter winds would lead to more
potential for frost. Only the far southeast areas both nights
might stay just above freezing. Even in the southeast, rural
areas could see frost or freezing conditions away from the
larger urban areas on either night.

Temperatures moderate by the weekend. EC still shows more
upper level ridging, which would maybe hold most of the showers
to the north and west of our area. However, large scale pattern
shows some variation from model to model. Overall the large
scale pattern supports wetter than normal conditions overall.

Also an interesting note. 12Z EC really cranks up the low off
the southeast coast. Something to watch.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR conds are expected to continue through 00Z Monday with high
(> 90%) confidence. Some brief borderline or high end MVFR CIGS
will occur INVOF KBFD through 22Z.

Stratocu, topped by Altocu will have bases mainly between 045
and 060 this afternoon across the Ridge and Valley Region, with
BKN-OVC CIGS based AOA 10000 FT AGL in the SE.

West to WNW winds will gust between 15-20 kts across the Central
and NW Mtns, in the wake of a weak cold front crossing the
region. Winds will be notably lighter across the Susq Valley
until picking up by 5-10 kts for up to several hours late this
afternoon/evening in the wake of the Cfropa.

WNW Winds diminish to under 6 KTS overnight and skies clear
out.

Outlook...

Mon...No sig wx expected.

Tue...Slight chance of evening showers/cig reductions NW Mtns.

Wed...Showers move in west-to-east from rain early, continues
throughout the day. TSRA possible SW late PM.

Thu...Clearing as high pressure builds into the area.

Fri...Mainly dry, but increasing clouds late.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Freeze Warning from 2 AM to 8 AM EDT Monday for PAZ019-025>028-
034>036-045-046-049>053.
Frost Advisory from 2 AM to 8 AM EDT Monday for PAZ056-057-059-
063>066.

&&

$$

SYNOPSIS...Fitzgerald
NEAR TERM...Fitzgerald
SHORT TERM...Fitzgerald/Dangelo
LONG TERM...Martin
AVIATION...Lambert