358
FXUS61 KCTP 160259
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1059 PM EDT Sat Jun 15 2024

.SYNOPSIS...
* Canadian high pressure will build southeastward into
  Pennsylvania this weekend, providing sunshine, seasonable
  temperatures and low humidity on Sunday.
* An anomalous subtropical ridge will build over the East Coast
  next week, accompanied by an extended period of hot and humid
  weather.

&&

.NEAR TERM /THROUGH SUNDAY NIGHT/...
High pressure will continue to to build to the northwest of
Pennsylvania with cloud cover breaking up across central and
western Pennsylvania this evening. Cirrus associated with a weak
shortwave will continue to drift towards the western periphery
of the area early this evening. Cloud cover, while expected to
be thin, will be one of two main deterrents for any fog
formation across northern PA overnight into Sunday morning
coupled with dry air at the lower levels.

The thin nature of cirrus clouds will still allow for
radiational cooling across the region overnight and have
continued to cut back NBM MinTs, with low temperatures ranging
in the mid-40s to the mid-50s which will be near-to-slightly
below climatology for the middle of June.

The surface high will move east of Pennsylvania on Sunday, but
continue to allow for mostly to partly sunny conditions and
slightly warmer temperatures with southerly flow. The bulk of
central PA will lower 80s outside the highest elevations of
Schuylkill County and the northern mountain zones with MinTs
dipping into the 60-65F range, but could trend lower with some
potential for radiational cooling depending on northward
positioning of the ridge.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
A subtropical ridge will begin to build along the East Coast
with the passage of a surface warm front on Monday allowing for
increased heat and humidity during the early stages of the work
week. Cannot rule out a SChc of a shower/storm over the the
higher terrain of the Allegheny Plateau on Monday where the best
forcing and moisture will be available. Otherwise, it will be a
very warm and increasingly humid afternoon.

Heat and humidity takes hold over all of central PA on Tuesday,
with an outside chance of a shower/storm across the northern
tier during the afternoon and evening hours. MaxTs ranging from
the lower-to-upper 90s, coupled with dewpoints in the upper 60s
to the lower 70s will allow for heat index values to push
close to and slightly above the 100F mark across the Lower
Susquehanna Valley with upper 90s elsewhere outside of the
Laurel Highlands.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Temperatures will easily rise into the 90s through the extended
forecast period. Some question as to ultimately how high
temperatures will make it as central PA does typically struggle
to realize even the best outlooks for extreme heat. The last
event to touch 100 degrees came on the heels of a dewpoint
bomb in a localized sector of north central PA. In any event,
it will be anomalously hot with concerns for the elderly, pets,
and the general populae.

Mesoscale models are painting a precipitation chance on Tuesday
afternoon/evening. This may be realized as hot air accelerates
up the mountain ridges - giving it enough upward momentum to
touch off a few isolated showers/TSRA. Similar to a 1970s kid
making epic jumps on their bike over a perfectly shaped hill at
the elementary school - complete with a Fred Patek baseball
card in the wheel spokes providing the motorcycle sounds. The
atmosphere mirrors life - if you let it.

Otherwise, Tuesday through Thursday appear to hold the best
chance for the highest temperatures as 500 mb heights hang
around 600dm with a mid June sun angle.

Even as temperature relax toward next weekend, we may still see
temperatures above 90 areawide.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
High pressure is bringing high confidence in widespread VFR
conditions through the forecast period. Winds will be light and
variable overnight before becoming light southeast on Sunday.

Added VCFG to KBFD and KIPT as overnight low temperatures will
drop to today`s afternoon dewpoints. This a lower confidence
(20%-30%) forecast as conditions have been relatively dry and
the nights are as short as they get so temperatures will only
briefly bottom out at these values.

Outlook...

Sun-Thu...Predominantly VFR, with building heat next week.
Density altitude concerns possible.

&&

.CLIMATE...
A period of much warmer than average temperatures is expected
across much of central Pennsylvania next week, with record high
temperatures being challenged. The record high temperatures for
some sites across central PA are outlined below:

 Jun 18 Jun 19 Jun 20 Jun 21

Harrisburg      97/1957     98/1994     98/1931     98/1923
Williamsport    97/2018     96/1929     101/1923    97/1933
State College   94/1923     94/1931     94/1953     94/1988

&&

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

&&

$$

SYNOPSIS...NPB
NEAR TERM...NPB
SHORT TERM...Evanego/NPB
LONG TERM...Tyburski
AVIATION...RXR/Tyburski
CLIMATE...NPB