Scientific Forecaster Discussion

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Area forecast discussion 
National Weather Service State College PA
1009 am EDT Wednesday Apr 23 2014

Synopsis...

High pressure will build in from the Great Lakes today...with
gusty winds and much cooler air. Cool and dry weather is expected
to continue Thursday...as the high slides east over the area.
Clouds will increase Thursday night and another cold front will
bring our next chance for showers on Friday.

&&

Near term /through tonight/...

An extensive blanket of cold air strato-cumulus remains over the area
as the weather pattern more resembles winter than early Spring.
The clouds will begin to scatter out today over eastern and
central areas...but the clearing will tend to be slow from central
PA westward as the low level cold advection takes its time
weakening.

Maximum temperatures will be well below normal...varying from the lower to
middle 40s across the mountains...to the middle 50s in the southeast.

The air is cold enough across the northwest mountains to keep the bands
of lake effect showers mainly in the form of -shsn. Elsewhere
across the northern and western mountains...a mix of light rain and snow showers
will be possible...but overall accums if any will be
insignificant.

Northwest winds and gusts will increase through the late morning into
the afternoon hours as vertical mixing increase within the low to
middle level thermal trough. Wind gusts will be around 30kts in many
locations today...based on BUFKIT soundings and momentum
transport. Some gusts around 35 kts are likely across the ridge
tops.

Clearing skies and a light to moderate northwest breeze will lead to
quite cold temperatures for late April...ranging from the middle to upper
20s across the northern and western mountains...to the middle 30s in the southeast.
The breeze should limit frost to the patchy variety in sheltered
valleys...so no flags for now west/respect to frost advisories.

&&

Short term /Thursday/...
a north/South Ridge of high pressure moves over the state Thursday
afternoon. This weather feature will bring decreasing wind in the
afternoon...along with abundant sunshine for most of the day.

High temperatures will rebound by a solid 8-12 f compared to Wednesday.

&&

Long term /Thursday night through Tuesday/...
middle clouds will increase late Thursday across the far west...and
over central and eastern portions of the County Warning Area Thursday night.

Still looking at showers on Friday...with the next system.
Did not add thunder at this point...as the triple point looks
to be just south of central PA. Temperatures will be on the mild
side...given warm advection and temperatures at 850 mb.

Did cut back on showers for Saturday night...given northwest
flow and spread in models.

Went with a dry forecast for Sunday into Monday.
However...did lower temperatures some Monday...given the
airmass in place and NE to southeast flow.

Large cutoff to the SW next week with a Rex block.
There could be some showers late Tuesday. Potential for
a several day period of wet and cool weather.

&&

Aviation /14z Wednesday through Sunday/...
Post-frontal northwest winds off the eastern lakes have produced an
extensive stratocumulus deck with MVFR/IFR ceilings isolated rain showers from
kbfd to kjst. Speed of the northwesterly surface winds /15-20kts with
gusts to 30kts/ could also be a concern to flying interests.

MVFR/IFR continues into Wednesday in west and north...with a breezy northwest
wind. Conditions will improve late this afternoon and overnight.

Outlook...

Wednesday...MVFR north/west with scattered -shra...VFR elsewhere. Breezy northwest
winds.

Thursday...VFR. No sig weather.

Fri-Sat...MVFR with chance rain showers.

Sun...VFR. No sig weather.

&&

Fire weather...
min rhs drop to the 30-35 percent range across portions of the
south central mountains and lower susq River Valley this afternoon
/with upper 30s and lower 40s relative humidity values across the northern and
western mtns/.

Sustained west-northwest winds of 12 to 18 miles per hour with gusts of 25 to 35 miles per hour
are expected today along with fine fuel moistures in the 10-15
percent range. Through collaboration with bof officials and
surrounding National Weather Service offices...we decided to cancel the Fire Weather
Watch for today /though conditions will still support an elevated
threat for fire growth/.

Posted a Fire Weather Watch for about the eastern third of the
County Warning Area for late Thursday morning through early Thursday
evening...since wind gusts will still be moderately strong
there...and fine fuel moisture and rhs will continue to decrease.

&&

Ctp watches/warnings/advisories...
Fire Weather Watch from Thursday morning through Thursday
evening for paz051>053-056>059-063>066.

&&

$$
Synopsis...la corte
near term...la corte
short term...Fitzgerald/Lambert
long term...Lambert/Martin
aviation...Ross/devoir
fire weather...