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000
FXUS61 KPBZ 200721
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
321 AM EDT Sat Apr 20 2024

.SYNOPSIS...
Seasonably cool temperatures and dry conditions are expected
through the weekend with potential for frost/freezing
conditions both Sunday and Monday morning. Building high
pressure will return above average temperatures mid-week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
KEY MESSAGES:

-  Dry and relatively cool conditions are expected.
-  No Hazardous weather.

------------------------------------------------------------------

An upper trough will cross the region today, maintaining cold
advection and resulting in temperatures slightly below average.

Gusty winds will develop during the afternoon as stronger winds
aloft integrate within the boundary layer. NBM probabilities of
wind gusts exceeding 20mph are near 100% with a period of gusts
exceeding 30mph along the timeframe of the trough passage.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
KEY MESSAGES:

- Slightly below average temperature and dry weather expected
  to continue through the weekend.
- Potential for frost and/or freeze impacts Sunday and Monday
  morning.
----------------------------------------------------------------

High pressure will continue to build in from the west,
maintaining dry conditions through the weekend.

A Freeze Watch was issued for tonight into Sunday morning as
much of the forecast area is now in the growing season and
latest HREF guidance has between a 60% and 80% chance of see
32F or low overnight across the majority of the forecast area.,

Confidence is medium as winds and cloud coverage could be a
limiting factor.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
KEY MESSAGES:


- The next low pressure system and associated precipitation
  chances is likely for late Tuesday into Wednesday.
- Ridging is favored for the late week period, pointing to
  rising temperature heading into the weekend.
-------------------------------------------------------------------

Though ensemble models vary in trough analysis moving across the
southeast U.S. Monday, the outcome remains the same for the
Upper Ohio River Valley: rising heights aloft and the influence
of high pressure will support dry conditions and seasonable
temperature Monday.

There is fairly high consensus on the next upper level trough
and associated surface low to drop from the north central plains
through the Great Lakes late Tuesday into Wednesday. Ahead of
the system, weak warm advection will support above normal
temperature and increasing cloud cover before the system`s
arrival. Widespread showers and low probability thunderstorms
are then likely as the system crosses the region. Depth of the
upper trough remains the biggest uncertainty during this period,
which will strongly influence the timing of precipitation
passage and degree of cold advection behind the system.

The late week period will be defined by the progression of the
upper trough through the northeast CONUS and the rapidity of
height rises in its wake. Dry weather will be favored given
high confidence of surface high pressure, with the degree of
temperature recovery in the post-cold front passage environment
dictated by said height rises.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
Broad upper troughing and impinging surface high pressure will
support VFR conditions and erosion of sub-5kft stratocu layers
during the early morning hours today, leaving waves of mid to
high level clouds. Shortwave passage this afternoon will push
through a secondary cold front, promoting slight veering of wind
profiles to NW and reinforce sfc gradients that promote 20 to
30kts daytime gusts. No precipitation is expected with the
front.

.Outlook...
High confidence in VFR conditions through a majority of Tuesday
under the influence of high pressure. Passage of a low pressure
system will bring widespread precipitation and restriction late
Tuesday into Wednesday. Ensemble models favor dry weather and
VFR conditions to end the work week.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...Freeze Watch from late tonight through Sunday morning for
     PAZ007>009-013>016-020>022-029-031-073>078.
OH...Freeze Watch from late tonight through Sunday morning for
     OHZ039>041-048>050-057>059.
WV...Freeze Watch from late tonight through Sunday morning for
     WVZ001>004-510>513.

&&

$$

SYNOPSIS...34/88
NEAR TERM...Hefferan/34/88
SHORT TERM...34/88
LONG TERM...34/Frazier
AVIATION...Frazier