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fxus61 kctp 250119 
afdctp

Area forecast discussion
National Weather Service State College PA
819 PM EST Tue Jan 24 2017

Synopsis...
a deep storm near Cape Cod will continue moving away from the
region. High pressure and unseasonably mild conditions will
briefly return for Wednesday before a new cold front moves
through late Wednesday night and early Thursday. Breezy and
colder weather will continue through the end of what has been a
very mild month.

&&

Near term /until 6 am Wednesday morning/...
the last remnants of a weakening band of light snow/rain are
moving through my northestern counties. Precip will continue to become
less and less likely overnight as high pressure approaches from
the west.

Upslope flow over the west could produce a bit of interest
tonight with the potential for some light drizzle to develop.
Temps may be just cold enough over parts of the northwest mountains for
a bit of freezing drizzle. Chances too low to do anything about
it now, but will have to keep an eye on that through the
evening.

&&

Short term /6 am Wednesday morning through Wednesday night/...
high pressure does crest over the area Wed am, and 800 mb temps
should rise to +4 to +8c across the County Warning Area. Maxes with the
downslope, higher mixing and no snow cover in the southeast could be
near 50f, but the snowier places will strain to get above 40f.
Clouds will thicken and lower late in the day over the west as
next system approaches. But, will keep pops out of the area for
the daylight hours.

Though it will be a light quantitative precipitation forecast event, pops will become quite high
over the northwest half of County Warning Area Wed night as low pressure slides in from
the Midwest. Pops slower to rise over the eastern and southern
portions of County Warning Area as low lifting to the NE as it passes. Overall,
temps remain warm enough for precip to remain all rain through
10z Thu before a cold front brings colder air in from the west
and begins to mix snow in with the rain over the northwest mtns.

&&

Long term /Thursday through Tuesday/...
all medium range models and efs are in good agreement and have
been consistent in showing a well-defined pattern change from a
more active and southern stream dominant pattern, to northwest
flow.

A highly amplified/anomalously strong upper ridge and sprawling
sfc high will set up along the West Coast and Great Basin area
respectively, while several short waves help to carve out a
large scale and highly meridional trough east of the Mississippi
beginning Thursday, and lasting right through the end of this
month.

An initial, then secondary cold front (trailing south from low
pressure over southeastern canada) will push southeast across the
commonwealth on Thursday, with lingering rain showers, mixing
with and changing to snow showers, and becoming more frequent
across the northwest mtns during the afternoon and evening.

This pattern change will result in frequent snow showers across
the alleghenies and Laurel Highlands, with a few to several
inches of snow accum likely accumulating each 48 hour period.
Periods of more significant les will occur across the perennial
northwest PA snowbelt where some les advisories/watches or even minimal
warnings may be needed.

Across the Central Ridge and valley region, expect mostly cloudy
to cloudy skies from stratocu of varying thickness with
flurries and scattered snow showers.

Some periods of sunshine will likely be limited to the middle
and lower Susquehanna valley where just some brief flurries
will fly from time to time.

Thursday and Friday will be the windiest days with gusts likely
in the 25 to 30 kt range both day (and even some higher gusts
possible across the mountains, and to the southeast of gaps in the
ridges).

Expect a prolonged period of seasonably cold daytime
temperatures (mainly in the 20s to at times near 30f across the
northern and wrn mtns, and 30s to near 40f elsewhere throughout
the central and southern valleys) with min temps at night
likely a few to several deg f above normal as a result of the
extensive cloud cover in most areas, and periods of breezy/windy
conditions.

&&

Aviation /01z Wednesday through Sunday/...

As the winter storm continues to move to the northeast, strong
northwesterly flow continues to develop. Upslope flow over the
west will keep mainly IFR and lower conditions in place through
most of the overnight period. Latest short term models have
moisture waning, which should allow for cloud ceilings to lift
slightly between 03z to 09z at bfd adn jst. However IFR and
lower cigs and vsbys should persist through morning. Expect
conditions to slowly improve as morning continues Wednesday.
Elsewhere, light showers should persist at aoo through 03z
before slowly fading by 06z. MVFR cigs should continue overnight
as the moist low levels will keep persistent stratocu. There
remains a slight chance for the potential for drizzle to
develop. Temps may be just cold enough over parts of the northwest
mountains for possibly a bit of freezing drizzle.

Conditions improve to VFR areawide (latest in the northwest mtns) on
Wed as high pressure traverses the region. Restrictions spread
in from the west again Wed night as another low pressure system
brings light rain back into the region.

Outlook...

Wed...low cigs early western 1/2. Otherwise VFR. Breezy late.

Wed night...light rain moves in from the west. Restrictions
slowly spread from northwest to southeast.

Thu-Fri...MVFR/IFR in snow showers west. MVFR to VFR east.

Sat-sun...MVFR in snow showers west. VFR east.

&&

Climate...
yes, it snowed over much of the area, but the month of January
is still way above normal on temperatures. For example, there
have been 13 out of the 23 days this month have been 9 or more
degrees above normal. Kipt is 5.9 degs above normal for the
month so far, and kmdt is 5 degs above normal for the month.

&&

Ctp watches/warnings/advisories...
none.

&&

$$
Synopsis...la corte/rxr

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