Area Forecast Discussion
Issued by NWS
FXUS61 KPBZ 292113
Area Forecast Discussion
National Weather Service Pittsburgh PA
513 PM EDT Wed Mar 29 2017
Another low pressure system brings rain to the region late
Thursday through Friday.
.NEAR TERM /THROUGH THURSDAY NIGHT/...
Only a few tweaks to cloud cover and hourly temperature curves
into the evening hours. A slow increase in clouds is figured for
tonight in a developing warm advection pattern. Overnight low
temperatures, on the warmer side of the guidance suite, look
good in this scenario.
Models are in some agreement with precipitation moving through
the region from south to north Thursday with 850mb boundary, but
am still unsure on just how aggressive to go with pops along the
boundary. Decided to go no higher than low chance during the
afternoon with the 850 boundary, then decided to ramp up pops as
occluded front moves from west to east Thursday night. The
occluded front appears as if it may arrive later Thursday night
than previously forecast, but have stuck with categorical pops
for most locations overnight. Temperatures over the next 24
hours will be the coolest they have been in about a week, with
overnight lows above normal Thursday night in the warm sector.
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
Showers will continue everywhere Friday morning, with the
chances for showers beginning to diminish Friday afternoon and
Friday night. Lingering low level moisture may keep widely
scattered showers possible through the first part of Saturday
before building subsidence brings an end to precipitation. Above
normal temperatures are forecast on Friday before dropping to at
or slightly below normal values for Saturday.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
While the second half of the weekend will be dry, showers will
begin to threaten the area on Monday, with Monday night having
the greatest chance for showers. While showers could possibly
hold on into Tuesday, a bit of model uncertainty develops for
the timing of the next low pressure system to arrive. Some model
guidance shows rain moving in on Wednesday, with other guidance
delaying rain until Thursday. Temperatures will generally stay
close to or slightly above average for early April.
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
VFR under clear skies will last through late this evening. High
clouds will begin to stream in from the west and southwest
overnight. Increasing low-level moisture will then begin to pool
west of the Ridges tonight, ahead of a warm front. A descent to
low VFR is expected through the duration of the TAF period,
with rain chances increasing Thursday morning/afternoon.
Outlook... Restrictions are likely again from late Thursday
through Saturday as another broad low affects the Upper Ohio