Area Forecast Discussion Issued by NWS Pittsburgh, PA
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000
FXUS61 KPBZ 160925
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
525 AM EDT Sat Mar 16 2024
.SYNOPSIS...
High pressure will keep the area dry on Saturday. A cold front
will bring another round of rain Saturday night. Below average
temperatures and snow returns early next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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KEY MESSAGES:
- Clouds will decrease throughout the morning with weak
ridging.
- Patchy fog is expected through dawn (mainly in eastern OH) for
areas that experienced prolong clearing.
- Quiet, dry conditions will persist through Saturday evening.
GOES-16 Microphysics RGB depicts valley fog developing in
eastern OH given radiational cooling under a clear sky, light
winds, and sufficient ground moisture from recent storms. Fog
will dissipate quickly after dawn with diurnal heating.
Adjustments have been made to clouds and temperatures as
lingering low-lvl clouds start to decrease in coverage as
under weak ridging. Areas within the ridges and near I-80 will
likely hold on to clouds the longest due to upsloping and lake
induced moisture.
Breezy conditions are expected today with deep boundary layer
mixing and as a low pressure system tracks to our northwest.
Probability of 20mph wind gusts is high across the region,
however 25mph to 30mph gusts will likely be confided to the
ridges and northwest of Pittsburgh.-- End Changed Discussion --
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.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
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KEY MESSAGES:
- Precipitation chances return after 8pm with a passing cold
front.
- A wintry mix may develop in elevations above 3kft after 5am
Sunday with cold advection.
- Snow chances return Sunday, mostly north of Pittsburgh, due to
lake enhancement.
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A trough, currently north of Minnesota, will continue to track
across the Great Lakes Saturday afternoon/evening and return
cold air to the region. However, with ridging noted over the
Midwest, 850mb temps may not fall too drastically and still keep
afternoon high temperatures for Sunday near average.
With fetch over the Great Lakes directed from the west, lake
enhanced snow showers Sunday afternoon and evening will likely
remain focus near I-80. With warm surface temperatures and a
high sun angle, snow accumulation is not expected.-- End Changed Discussion --
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.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
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KEY MESSAGES:
- Cold temperatures are expected to linger through Tuesday
- Lake enhanced snow is expected Sunday night into Tuesday.
- Wind chill values will be abnormally cold early Tuesday (teens
in the lower elevations/single digits to below zero in the
higher terrain).
- Above average temperatures return mid-week.
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Long range ensemble models continue to favor a cold pattern
across the Ohio River Valley late Sunday into Tuesday across
the Great Lakes. Arctic air will drive high and low temperatures
to be below average by 5 to 10 degrees Monday and Tuesday.
Probability of low temperatures below 25F Tuesday morning is
55% or higher near I-80 and in the ridges.
As a large upper-lvl low pivots out of the Great Lakes and
enters New England, flow off of Lake Erie will shift from the
west to northwest. Therefore, snow shower potential will drift
further south of I-80 Monday afternoon into Tuesday. Probability
of one inch of snow for both days is less than 15% across the
region. Probability of >= 0.1 inches of snow is elevated (above
70%) within the ridges due to upsloping and confided along I-80
(in close proximity to the lake). Accumulation will likely be
focused during the overnight time period, when sfc temperature
fall near or below freezing.
With a strong gradient wind associated with the low and cold
advection, expected wind chill values to be abnormally cold
early Tuesday. Teens in the lower terrain, single digits to
below freezing in the ridges of PA/WV.
Increase fetch over the lake with a new shortwave may keep snow
showers in the region into Wednesday. However, accumulation will
likely be very little given a building ridge to the west.
Near to above average temperatures are expected to mid-week into
Friday. However, precipitation chances may return as a trough
advances across the Southeast and tracks north along the East
Coast.-- End Changed Discussion --
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
Areas of MVFR cigs will continue overnight, with the latest PIT
00Z and model soundings showing moisture below a subsidence
inversion. These clouds should continue to slowly erode as a
ridge of high pressure begins to build in, though they are
expected to persist the longest across areas from FKL-BTP-LBE
and point east. The clouds should clear by late morning as the
ridge moves across the Upper Ohio Valley region.
Mid and high level clouds are expected to increase later today
as a cold front approaches from the Upper Great Lakes region.
This front will cross the Upper Ohio Valley region tonight
through early Sunday, with showers and MVFR restrictions
expected. In addition, SW wind gusts to 20kt are expected with
mixing and a tightening pressure gradient ahead of the front. A
WSHFT to the NW, with additional gusts to 20kt are expected
after the late Saturday night FROPA.
.Outlook...
Gusty NW wind is expected Sunday behind the exiting cold front.
Restrictions and scattered snow showers return Monday night and
Tuesday with a reinforcing cold front and subsequent upper
troughing. VFR returns Wednesday as a ridge of high pressure
builds in.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.
&&
$$
SYNOPSIS...Hefferan
NEAR TERM...Hefferan
SHORT TERM...Hefferan
LONG TERM...Hefferan
AVIATION...WM