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Latest PA Weather Summary:


000
AWUS81 KCTP 300949
RWSCTP
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-
049>053-056>059-063>066-010000-

Regional Weather Summary
National Weather Service State College PA
549 AM EDT Fri Sep 30 2022

After a frosty start to the day with near-freezing conditions
across the Northern Mountains today will feature sunshine
gradually fading behind a thickening layer of high clouds
that will be advancing from the south.

High temperatures this afternoon will vary from the upper 50s over
the highest elevations of Northern and Western Pennsylvania, to
the mid 60s throughout the Susquehanna Valley.

A 4 to 6 hour period of rain, associated with the remnants of
Hurricane Ian, will spread north across the Commonwealth late
tonight through the mid morning hours Saturday before
transitioning to periods of mainly drizzle late Saturday morning
and afternoon. Lows tonight with be in the mid 40s across the
higher terrain to low 50s in the Southeast Valleys.

High temperatures Saturday may struggle to reach the mid 50s
throughout much of Central and Northern Pennsylvania, while
residents in the Western low lands and Southeast temperatures
peaking in the upper 50s to low 60s.

Overcast skies with periods of rain and drizzle will continue for
Saturday night and Sunday.

Relatively light East to Northeast winds today will increase and
gust into the 20 to 30 mph range on Saturday.

$$

Lambert

Latest Forecaster's Discussion:


000
FXUS61 KCTP 301515
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1115 AM EDT Fri Sep 30 2022

.SYNOPSIS...
High clouds will thicken across the region this afternoon,
but some sun will filter through the clouds.

A 4 to 6 hour period of rain, associated with the remnants of
Hurricane Ian, will spread north across the Commonwealth late
tonight through the mid morning hours Saturday before
transitioning to periods of mainly drizzle late Saturday morning
and afternoon.

Periods of rain and drizzle will continue for Saturday night
and Sunday.

Relatively light northeast winds today will increase and gust
into the 20 to 30 mph range on Saturday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Fog lifting up now, main area from the local area southward
toward Bedford. Fog and areas of low clouds protected much
of the area from much frost last night. BFD did touch 32 degrees
at 7 AM, as the sun was coming up, so not likely long enough
to damage gardens too much, just certain things like pepper
and tomato plants, that are quite sensitive to temperatures
at that level. Anyway, main change was to adjust cloud cover
in the forecast here at mid morning. Still potential for some
sun today, through the mid and high clouds, especially across
the north and west.

Earlier discussion below.

A +1-2 Standard Deviation area of surface high pressure will
extend from the Great Lakes to the England State today,
followed by a +2-3 Std Deviation drifting southeast from
Manitoba and Northern Ontario Saturday and Sunday. These weather
features will combine with the approaching remnants of Hurricane
Ian to enhance a highly anomalous East to Northeast wind today
through Saturday.

First off, a Frost Advisory remains up for roughly the northern
half of the forecast area. However, confidence in widespread
frost is greatest over the northwest corner of the CWA due to
the factors noted above. Expect temps at sunrise today to range
from around 32F in the normally colder valleys of the northwest
mountains, to the upper 40s over Lancaster County, where skies
should be mainly cloudy.

A calm wind and air/water temperature differences of around 30
degrees should be more than sufficient to produce locally dense
fog in the valleys of northern Pa late tonight

Look for a mostly sunny start to the day today across all of
the CWA except for the Lower Susq Valley, followed by a
thickening layer of cirrostratus spreading across the southern
half of the state late this morning and this afternoon. High
clouds move into the northern half of the CWA this afternoon and
evening, before lowering their bases to below 10 KFT AGL
between 06-12Z Saturday.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
Lowering and thickening clouds advance northward tonight on the
northern periphery of Ian as it makes an extratropical
transition tracking from central SC to western NC by the end of
the period/12Z Sat.

All model guidance brings rain into southern PA late tonight
night into early Saturday morning. Max POPs are along the MD
line with QPF amounts 0.25-0.50 inch. Little to no rain through
12Z Saturday is fcst north of I-80.

Min temps trend much warmer night/night into the low 40s-50s
range with 24hr deltas of +5 to +15F.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Remnants of Ian dominate the first two days of the long term.
Main takeaway is that we`re getting off easy. The big high
overhead/to our north will deflect most of the moisture. QPF
looks lower than anything needed to cause any problems, even
along the MD border where the 1-1.5" numbers are expected. All
that will fall over a long time span, and not all at once. But,
it will be somewhat tropical/warm rain at first, so it /could/
overperform on Sat, but likely not. Then the moisture will be
limited in height/altitude and PWAT values drop back near 1"
after a their peak of 1.7" early Sat (values at KLNS from GFS
soundings).

Rainfall should be ongoing across the srn tier as the period
begins. However, the mass fields show a notable split between
the upper low/cutoff associated with Ian and the sfc
low/reflection.

As the depression hits the big high currently overhead, the
upper low of the storm goes west or sits still, while the sfc
low slides off the East Coast, and modifies/fills.

The dry slot helping this happen hits Central PA during the late
morning and afternoon hours on Sat. Therefore, the PoPs and QPF
may be overdone slightly for the central mtns (N of the
Turnpike) which is already low (<0.50") anyway.

A transition to a more shallow, warm cloud regime will occur for
Saturday afternoon, which will support mainly periods of
drizzle for the afternoon and early evening hours,

The skies could possibly part for outdoor activities on Sat
aftn after the aforementioned rainy start. Will continue to run
with PoPs close to NBM (and not too far from prev fcsts) due to
the mod uncertainty still around with the dynamics and deepest
plume of moisture.

Strong NErly flow throughout the weekend will attempt to dry
things out and make it more sunny than current thinking esp
across the N. Again, we`re making small moves in this time
frame, and keeping cloud cover p/s at best for most of the area
esp the srn tier which should be m/c.

The compact upper low over the central Appalachians will open
up into a narrow/sharp trough through the weekend, and begin to
swing eastward. However, it may cut off again as it gets near
the coast and gets close to the warm Gulf Stream waters. Thus,
will maintain low POPs over the southeast part of the CWA into
early next week.

Medium range guidance is in alignment the second half of next
week, lending confidence to a forecast of fair and seasonal
weather Wednesday under upper level ridging. A cold front should
push southeast across the area Thursday PM. However, this
feature will have little moisture to work with. Latest ensemble
plumes only support low POPs across the northwest mountains,
with a dry fropa likely elsewhere.

GEFS 2m temps indicate temperatures will remain below normal
across southern Pa Sun-Tue, due to cloud cover and easterly
flow off the Atlantic. Warmer conditions are likely areawide by
midweek, as the upper low over the Mid Atlantic finally lifts
out.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
Adjusted TAFS late this morning to add some more detail in
toward 12Z Saturday.

For this afternoon, looking at VFR conditions with dry weather.

Lowering conditions late tongiht into the weekend.

Outlook...

Sat-Sun...Pds of rain/low cigs primarily over the southern 1/2
of the airspace.

Mon-Tue...Chance of rain showers lingers mainly over parts of
southern and eastern PA.

&&

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

&&

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

Latest Public Information Statement:


000
NOUS41 KCTP 291316
PNSCTP
PAZ024-033-034-300000-

Public Information Statement
National Weather Service State College PA
916 AM EDT Thu Sep 29 2022

...NOAA WEATHER RADIO ALL HAZARDS STATION PLANNED OUTAGE IN
JOHNSTOWN FRIDAY SEPTEMBER 30TH...

NOAA Weather Radio All Hazards Station WXM-33, located in
Johnstown, will be off the air on Friday, September, 30th from
approximately 9 a.m. to 12 p.m. for scheduled maintenance.

We apologize for the inconvenience.

$$
MRS/BAC