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000
FXUS61 KCTP 220317
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1117 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/...
Late evening satellite loop is showing a patch of cirrus lifting
into south-central PA associated with a potent shortwave over
the Southern Appalachians. Linear extrapolation points to partly
cloudy skies across the southeast part of the forecast area
between 03Z-07Z, then clear skies for the balance of the night.

Mainly clear skies, a diminishing wind and anomalously dry air
will result in 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/...
High pressure passing off of the east coast and the return
southwest flow will result in a breezy and warmer Tuesday. All
guidance then points to a round of showers and a subsequent
cool down associated with a cold front passage Tuesday night
into Wed AM. The moisture return ahead of the front looks
unimpressive, but strong forcing ahead of a potent upper level
shortwave supports a good chance of measurable rainfall. Latest
plumes indicate most likely rainfall ranging from around 0.05
inches over the Lower Susq Valley, to around 0.4 inches over the
NW Mtns.

It appears there will be another chance of a frost/freeze Thu
and Fri AM, as Canadian High Pressure builds over the region.
Those with agricultural interests should keep an eye on the
forecast for the end of next week.

The next chance of rain will come Friday night into Saturday
associated with low pressure lifting into the Grt Lks and the
associated warm front approaching PA. Both the EPS and GEFS
indicate the warm front will lift north of the region by Sunday,
resulting in markedly warmer and more humid conditions with
scattered PM convection possible. Mean progged 850mb temps south
of the warm front are around 12C, supportive of highs in the
75-80F range.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
VFR conds will prevail through 00Z Tuesday with high (> 90%)
confidence as a SCT-BKN deck ~3000-4000AGL gives way to SKC
conds after 03Z Monday. Winds gusting up to 15kts will continue
through 02Z Monday before decreasing below 5kts sustained at
290-320 overnight. Winds will increase slightly towards 5-10kts
sustained with gusts up to 15kts late Monday afternoon into the
evening hours at 300-320.

Outlook...

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...Fitzgerald
AVIATION...NPB