Area Forecast Discussion Issued by NWS Pittsburgh, PA
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000
FXUS61 KPBZ 140732
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
332 AM EDT Thu Mar 14 2024
.SYNOPSIS...
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Mainly dry weather is expected early today as high pressure
moves east of the area. Shower and thunderstorm chances will
increase later today as a cold front approaches. A few storms
could be severe, mainly across Ohio. The front will slowly cross
the region tonight and Friday, with more widespread showers and
a few thunderstorms. Dry weather returns Saturday before another
cold front brings showers Saturday night.-- End Changed Discussion --
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.NEAR TERM /THROUGH TODAY/...
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KEY MESSAGES:
- Shower and thunderstorm chances increase from west to east
today
- A few severe storms are possible mainly across Ohio
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Shortwave ridging is expected to maintain dry weather this
morning. The ridging is then progged to gradually flatten
through the afternoon as a shortwave trough and associated
surface low pressure begin to approach from the Midwest.
Shower and thunderstorm chances are expected to increase from
west to east this afternoon as moisture and vorticity advection
occur in WSW flow aloft. The leading edge of a low level jet is
also expected across Ohio by late this afternoon, enhancing the
thunderstorm potential. MU CAPE values are forecast to range
from 250-500 j/kg. While instability is not optimal, the arrival
of the low level jet and increasing 0-6km shear will result in a
marginal potential for severe thunderstorms mainly across Ohio.
Areas farther to the east should see lower amounts of
instability, and a lesser severe weather risk. SPC has included
most Ohio counties in a marginal risk for severe weather this
afternoon and evening, and have included this potential in the
latest Hazardous Weather Outlook.
The Upper Ohio Valley region will be in the warm sector today,
with a stationary front across the Lake Erie-srn NY area. Model
soundings indicate mixing at least to 850 mb today. Even with
cloud cover from convection to our west increasing, high
temperatures should reach around 25 degrees above average.-- End Changed Discussion --
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.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
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KEY MESSAGES:
- Showers and a few thunderstorms tonight into Friday
- Marginal risk for severe storms mainly across Ohio this
evening
- Dry and cooler Saturday
- Shower chances return with a Saturday night cold front
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Convection should continue into the evening with increasing
jet supported ascent. The continued 0-6km shear from 40-50kt,
along with the limited instability, should maintain a marginal
severe weather potential across Ohio into the evening. The
potential for severe storms will begin to decrease as
instability gradually wanes.
The surface low is expected to track along the boundary to our
north. This boundary will then drop slowly southward as a cold
front, spreading widespread showers across the region. Scattered
thunderstorms are also expected, with soundings showing elevated
instability and a Showalter index below from -1 to -2. The front
is expected to make very slow progress to the south, as the
upper flow remains nearly parallel to the boundary.
Post frontal rain is expected on Friday, with showers and a few
thunderstorms expected south of the front. Precipitation is
expected to slowly taper off from N-S Friday afternoon and
evening as the front continues a slow progression southward.
Dry and cooler weather is then expected Saturday as the front
exits, and a ridge of high pressure briefly builds in. Shower
chances return Saturday night as a fast moving cold front
crosses the Great Lakes and Upper Ohio Valley region.-- End Changed Discussion --
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.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
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KEY MESSAGES:
- An active and colder pattern the first half of the week
- Snow shower chances return Monday and Tuesday
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Showers are expected to end early Sunday morning as a cold front
quickly exits the region. A persistent trough across much of the
eastern CONUS will then maintain scattered snow showers and
colder temperatures Monday and Tuesday as individual shortwaves
rotate through the trough. Generally dry weather is expected to
return Wednesday as the trough begins to move east, and surface
high pressure builds in.
Temperatures at 850mb are expected to drop to around -10 deg C
Monday into Tuesday, with below average temperatures returning.-- End Changed Discussion --
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.AVIATION /07Z THURSDAY THROUGH MONDAY/...
Confidence remains high that VFR conditions will continue into
the early afternoon time period under high pressure. Adjusted
wind gusts for the early afternoon, sufficient diurnal heating
should help mixed elevated wind gusts to the surface. Probabilities
are higher west of PIT after 16Z for 20kt gusts as a disturbance
builds over the Midwest.
Clouds will start to thicken during the late morning and
afternoon with a flux of warm, moist conditions under strong
southerly flow. However, confidence is still remains high that
ceilings will stay above 5000 feet. Remnant convection
developing in the Midwest this afternoon may track into the Ohio
River Valley late this evening. A few storms may be severe west
of PIT; PROB30 for -TSRA has been added to cover the uncertainty
of unorganized convection.
A descending cold front from Lake Erie to northern PA will
likely keep precipitation in the region into early Fri morning.
MVFR to IFR conditions will likely follow in the wake of the front
(between 06Z to 12Z Friday).
.Outlook...
Restrictions remain possible through early Saturday, either from
cigs and/or areas of fog.
VFR briefly returns later Saturday under high pressure, before
another cold front returns a restriction potential Sunday.
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.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.
&&
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SYNOPSIS...WM
NEAR TERM...WM
SHORT TERM...WM
LONG TERM...WM
AVIATION...Hefferan/CL