National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 150715
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
315 AM EDT Mon Apr 15 2024

.SYNOPSIS...
-- Changed Discussion --
A brief bout of dry weather is expected today before rain
chances return on Tuesday with moderating temperatures into next
week.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
KEY MESSAGES:

- The last of the showers/storms exit by dawn.
- Dry weather returns Monday with moderating temperatures.
-----------------------------------------------------------------

Along a line of convergence as of 05Z, the showers and
thunderstorms continue to track southeast through the area as
the line slides south. The instability in place is just about
spent and will expect the convection to weaken and become a few
showers or finally exit the area completely.

Upstream obs indicate dry air advecting into the area and the
gradient behind this decaying line of storms is still prevalent
with surface winds remaining at 5 to 10 knots respectively. This
may keep from fog development. The caveat may be if we clear out
and winds continue to decrease, there may be some development.
Probs on the NBM only give 30% to 40% of fog development.

With the progression of the upper trough into today, confidence
is high that the cold front will clear the area by mid-morning.
Aside from some low probability shower chances south of I-70,
the day should otherwise be dry. Ensembles aren`t very bullish
on a notable push of colder air in the wake of the front as an
850 mb ridge quickly builds counteracting weak cold advection in
residual northwest flow; most of the day should feature a
rather sunny sky with increasing subsidence drying out the
boundary layer and temperatures are expected to remain above
normal.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
-- Changed Discussion --
KEY MESSAGES:

- Rain chances return for the latter half of Tuesday and
  continue through Thursday.
-------------------------------------------------------------------

Brief upper ridging slides overhead on Tuesday reinforcing the
dry weather for the first half of the day, but clouds increase
from the southwest with increasing moisture aloft ahead of an
approaching shortwave traversing and flattening the ridge and
reintroducing showers for the second half of the day. We should
see a brief break overnight Tuesday night before trailing low
pressure arrives. Amounts with this batch look light with even
NBM 90th percentile values only near 0.1-0.2" through Wednesday
morning.

Above normal temperatures and rain chances continue to be the theme
into mid-week as southerly return flow promotes warm advection
kicking highs above average with ensemble probability for >70F in
excess of 70% through Thursday.

What`s left of the ridging breaks down into Wednesday as an upper
trough and surface low pressure dig across the Midwest with
diffluent flow aloft promoting broad ascent. Primary ensemble
uncertainty stems from the progression of the trough and surface
low, but consensus tracks it through the Great Lakes to our north as
it occludes and returns rain to our region by Tuesday with a leading
shortwave passing through. Rain chances continue into Thursday as
the warm front approaches with the cold front following behind as
early as Wednesday night or more likely more toward early Thursday
morning.
-- End Changed Discussion --

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
-- Changed Discussion --
KEY MESSAGES:

- Temperatures remain above average.
- Rain chances continue into mid-week.
- Temperatures return closer to normal by the end of the week.
-------------------------------------------------------------------

We`ll dry out briefly behind the front, but ensembles push a
secondary reinforcing trough through by late week which then
favors temperatures dipping back down towards normal to close
out the week and low confidence rain chances as early as Friday
morning, but more likely into Friday afternoon and evening.
Still early to talk rainfall totals, but ensemble spread sits
from 0.2" on the reasonable low end to near 1" on the high end
through Friday.
-- End Changed Discussion --

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
A band of redeveloping thunderstorms have set up across west
central/NW PA in a band of favorable instability, moisture and
shear. Expect this activity to shift slowly southward with a
southward moving surface cold front/trough, and become more
disorganized, and less severe as instability slowly wanes. MVFR
to IFR restrictions are expected as this activity affects
individual storms. Have included TEMPO groups for some ports
where it remains uncertain how far westward thunderstorm
development occurs, where warm air aloft has prevented
convection.

General VFR is expected behind the front as high pressure
gradually builds over the region. Mixing has resulted in strong
wind gusts today, and these should also gradually diminish
through this evening after the storms end.

.Outlook...
VFR is expected under high pressure Monday and most of Tuesday.
Restriction potential returns late Tuesday and Wednesday with
approaching low pressure. Restrictions are possible into
Thursday under a subsequent upper trough.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.

&&

$$

SYNOPSIS...Shallenberger
NEAR TERM...Shallenberger
SHORT TERM...Shallenberger
LONG TERM...MLB/Shallenberger
AVIATION...WM