Area Forecast Discussion
Issued by NWS State College, PA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KCTP 241552
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1152 AM EDT Wed May 24 2017

.SYNOPSIS...
Periods of wet weather with cooler-than-average temperatures
will dampen the area for the second half of the week. Widespread
rain is expected late tonight into Thursday, followed by shower
spells Thursday afternoon into Friday. Temperatures should
rebound modestly over the Memorial Day holiday weekend with a
chance for showers and thunderstorms.

&&

.NEAR TERM /THROUGH TONIGHT/...
Nice clearing this morning will give way to a low cloud deck in
the southwest and a steadily spreading/thickening high cloud
shield elsewhere this afternoon. The NE counties will probably
stay mo sunny/clear very late in the day. Timing of rain over
western PA is pretty solid with all the newest guidance still
on track with going fcsts. But, the new guidance does slow the
eastward progression by a few hours. Will nudge fcst that way
for the next 12 hrs. It should be spotty light stuff in the
west first, but increase in intensity through the evening. Have
added a deg or two to the maxes with the nice sunshine over most
of the area right now.

Prev...
10Z: Light rain is exiting the LSV pushing east into NJ. The
latest near term HIRES model and ensemble guidance still keeps
most of the area dry today as pcpn activity focuses to the
south/west across the OH Valley and Central Appalachians. Max
12hr POPs ending 25/00z are over the southwest 1/4 of the CWA or
in the Laurel Highlands late this afternoon/early evening.

Models remain consistent in bringing widespread rain over the
area tonight into early Thursday morning and have increased POPs
to near 100 percent for the entire CWA. Strong H85 moisture flux
anomalies and southeast low level jet combined with increasing
large scale forcing/ascent associated with amplifying upper
trough suggests some moderate to locally heavy rain amounts
(0.75 to 1 inch) are possible tonight with peak rain intensity
likely in the 06-12z Thursday period. The southeast low level
flow should enhance UVVS in the eastern upslope side of the
terrain where some local 1" pcpn maxes will be possible.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
The strong upper trough will pivot over the northern Mid
Atlantic states on Thursday, with low pressure at the surface
consolidating over PA Thursday night before lifting up the
NJ/New England coast Friday. Steadier rain Thursday morning
should lift north of the area with partial sunshine leading to
shower spells and perhaps a few T`storms in the afternoon. Broad
cyclonic/northwest flow with additional shortwaves rotating
around the departing upper low will keep showers in the fcst on
Friday before precip winds down Friday night/AM Saturday.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
A lower-amplitude mid level flow pattern in the wake of the
departing closed upper low will feature rising heights/weak
ridging aloft into the weekend. The pattern will evolve into a
broadly cyclonic flow regime by early next week with upper low
spinning between the Great Lakes and Hudson Bay into midweek.

There is still some uncertainty regarding the location and
timing of shortwave impulses that could be a factor for
convection on Saturday. Model and ensemble guidance still
favoring locations to the south/west of Central PA so a dry
start to the holiday weekend may be in store for the area.
24/00z NBM/ECE/WPC blend maintained the highest POPs on Sunday
with another round of showers/storms possible for Memorial Day.

&&

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
Steady rain now east of our area.

Adjusted 12Z TAFS.

Earlier discussion below.

Some showers across the southeast this morning. CIGS still VFR
across the southeast, but 4-5SM with the showers.

Few drops of rain near BFD.

CIG at JST low now.

Expect conditions to improve by mid to late morning. Overall
it should be a dry day with VFR conditions.

Next system will result in more rain. Rain will overspread the
area this evening from the west. Poor conditions will linger
at least Thursday, if not early Friday.

.OUTLOOK...

Thu...Rain/low cigs likely through at least midday.

Fri...Showers/MVFR cigs NW. Mainly VFR SE.

Sat...No sig wx expected.

Sun...Reduced conditions with scattered showers.

&&

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

&&

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.