863
FXUS61 KCTP 191603
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1203 PM EDT Fri Jul 19 2024

.SYNOPSIS...
* High pressure and northwest winds will bring ample sunshine
  and lower humidity today with seasonable temperatures.
* Southerly winds usher in an uptick in humidity on Saturday
  with scattered afternoon showers and thunderstorms.
* Dry conditions on Sunday into Monday precede a more unsettled
  pattern next week with seasonable temperatures.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure centered over northern Indiana late this morning
had a ridge extended east into PA. This weather feature will
supply us with abundant sunshine and just a scattering of fair
weather cu based between 3500-4500 FT AGL across mainly the
northern half of PA

Near normal temperatures and comfortable humidity levels will
continue today. Highs this afternoon will vary from the upper
70s over the highest elevations of the north and west to the
upper 80s in the Southeast Metro Areas.

Diurnal ranges of 20 to 30F are pretty typical for a relatively
dry summertime airmass. Dewpoints will remain in the 50s for
most today and could even mix out into the upper 40s in a few
spots, which will fell fantastic relative to the recent
prolonged stretch of hot and humid weather.

An approaching warm front is likely to spread increasing
clouds/humidity into the region Friday night, but the odds of
any rain look slim. High clouds will overspread most of the
forecast area by daybreak Saturday with lower clouds more
scattered in nature and focused across the spine of the
Appalachians. Patchy fog could again develop again tonight into
Saturday morning across the NW mtns given the increasing
moisture and scattered cloud cover expected, though coverage is
not expected to be as extensive as this morning. Morning lows on
Saturday will trend a few degrees warmer than this morning -
from the middle 50s in the northwest to upper 60s southeast.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A short wave disturbance will bring increased rain chances for
the afternoon on Saturday when isolated to scattered coverage of
showers and storms develops over parts of the Laurels, SC
Mountains and Central Mountains. Best chance for rain appears to
be along the spine of the Appalachians with current rainfall
amounts generally less than a tenth of an inch, with isolated
pockets exceeding 0.5 inches possible. Generally weak forcing
and shear should preclude any severe or flooding potential. In
fact, with expanding drought conditions across the region,
rainfall will be beneficial for all recipients.

There will be a noticeable uptick in humidity on Saturday for
everywhere except the northwest mountains with temperatures
staying pretty steady relative to Friday. High pressure will
retake control of our weather Saturday night with clearing skies
expected and patchy fog in locations that received rain earlier
in the day. Dry conditions prevail on Sunday with increasing
clouds but still partly cloudy skies. Temperatures will trend a
few degrees above normal Sunday afternoon as high temps across
the south approach 90 once again. Dry weather continues Sunday
night as clouds continue to stream in and humidity increases.
The uptick and clouds and humidity will help overnight lows
continue to moderate each day into next week.

&&8

.LONG TERM /MONDAY THROUGH THURSDAY/...
With the large-scale, upper-level pattern next week, it appears
that amplified ridge axes will stay in place across the
Intermountain West, as well as from the Southwestern Atlantic
into the Southeastern CONUS. In between these two ridge axes, a
mean upper-level trough axis will extend from Eastern Canada
into the Midwest and the Ohio Valley.

In general, the above described pattern will keep excessive
heat suppressed to the south and southwest of the Commonwealth.
However, southwesterly flow aloft will bring increasingly humid
conditions locally. Also, the proximity of the aforementioned
upper trough, as well as several surface fronts, will bring the
likelihood of diurnally driven (mainly during the afternoon and
evening hours) showers and thunderstorms, especially in the
Tuesday-Thursday time frame. The silver lining here is that
additional beneficial rains could be in the offing for drought
stricken sections of PA.

For the most part, we can expect daytime highs in the 80s and
overnight lows in the 60s, which is rather seasonable for mid to
late July. Some of our northern mountainous areas may see
afternoon highs stay in the upper 70s, while normally hotter
sections of the Lower Susquehanna Valley could sneak into the
lower 90s.

&&

.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
There remains high (> 95%) confidence in VFR conditions through
at least 06Z Saturday. SCT-possibly BKN cloud bases over the
ridges near the PA/NY border will be near 3000 FT AGL until 17Z
before lifting to 3500-4000 ft AGL.

Patchy fog is expected to be slightly more widespread than last
night with slightly higher confidence in fuel-alternate
restrictions at BFD after 08Z Saturday. LAMP guidance outlines
some potential for IFR conds as early as 06Z; however, have
hedged closer to persistence for this forecast cycle. There is a
bit of uncertainty on how far south fog mentions will be needed
with lower potential and confidence (20%) of restrictions at
UNV/IPT so have opted to show some gradual lowering of cigs/vsby
in the 12Z TAF cycle.

Outlook...

Sat-Mon...Primarily VFR/unrestricted conditions. Patchy late
night/early morning fog and low ceilings are possible.

Tue...More widespread PM showers and thunderstorms could lead
to at least brief restrictions.

&&

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

&&

$$

SYNOPSIS...Lambert/Banghoff
NEAR TERM...Lambert/Banghoff
SHORT TERM...Banghoff
LONG TERM...Jurewicz
AVIATION...Lambert/NPB