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Area Forecast Discussion
National Weather Service State College PA
1039 AM EDT Sun Sep 25 2016

.SYNOPSIS...
A large area of high pressure will keep it fair today. Low
pressure will move into the Upper Great Lakes in the first part of
the week, and push a cold front through the region late Monday
and Monday night. The forecast becomes less certain for the rest
of the week as a cut off low may form somewhere over the eastern
United States.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BFD right at 32 degrees earlier, but just for a brief time. Other 
sites in the mid 30s, so will keep all areas active for now.

Some clouds to the south of PA, but should be a fine fall day.

Minor adjustments made to the grids. 

Maxes should get into nearly- normal m60s- l70s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Sunset will allow it to chill off rather quickly in the evening,
but advancing mid-upper clouds over the west should slow the fall
or even stop it there. More interestingly, there will probably be
some low crud creep in on a light srly flow late tonight as the
axis of high pressure moves east and a cold front sweeps through
the OH valley. 

The front is tied to a low centered over the Upper Great Lakes, so
the front will be well-occluded as it arrives. The front is
progged to move through quickly. But, this is somewhat unusual for
the synoptic set-up. But, the progs are all very well-aligned and
confidence is high in fropa Mon night. Confidence also high in
rain for the area. POPs have been nudged higher. Certainty in
thunder is getting a bit higher, as well. SPC has placed the far
western part of PA into a MRGL risk for Monday- Night. Will
continue to mention thunder, but not make it categorical at this
point. 

Temps on Monday should start out cool in the NE, and mild in the
SW due to the difference in cloud cover/extent. Hints at dz/--ra
are present in the NAM and SREF mean POPs after lower clouds move
into the SC mtns. Will just draw a 20 POP in the first part of
the day. Maxes will probably be 65-70F on Monday.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Will linger only chc POPs in the far SE on Tuesday as a buffer of
uncertainty of speed of fropa. Temps should stay very near normal
for the balance of the week. Any lake effect showers under the
cool pocket behind this front are being kept to the north of the
CWA. 

A bit of intrigue has entered the forecast for the rest of the
week, as a previously possible cut-off upper level low is looking
more likely in these latest prognostic runs. Thus, what may have
been yet another dry period could turn cooler and wetter - or at
least cloudier in the latter half of the period. But, the
formation of cut- offs and their positions/decay/longevity are
always in question.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
No fog left. Will adjust TAFS as needed.

Earlier discussion below.

Clear skies and light wind will continue across central PA
today with high pressure in control. Chilly temps over relatively
warm rivers/streams has resulted in some fog in the deep valleys
of north central Pa. Doesn't look like any airfields will be
affected, and fog should mix out by 13-14z. 

After that, minimal clouds and widespread VFR for today through
tonight. A cold front moves through later Monday into Monday
night, which will bring a short period of rain and slight chance
tstms along with possible reductions. 

Outlook...

Mon...PM showers/Tstms with reductions possible.

Tue-Thu...No sig wx expected.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...Dangelo
NEAR TERM...Dangelo/Martin
SHORT TERM...Dangelo
LONG TERM...Dangelo
AVIATION...Martin/RXR

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