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599
FXUS61 KCLE 221100
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
700 AM EDT Sun Sep 22 2024

.SYNOPSIS...
A warm front will lift across the area today with a cold front
pushing east across the region tonight into Monday. A series of
disturbances will cross the area through Wednesday before high
pressure returns by the end of the week.

&&

.NEAR TERM /THROUGH MONDAY/...
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630 AM EDT Update...
Fog has expanded across interior NW PA so have issued a Dense
Fog Advisory that will expire at 13Z/9 AM. Otherwise, no changes
needed with this update.

Previous Discussion...
A ridge will briefly build over the area this morning into this
afternoon before exiting to the east by this evening. Light
winds, low level moisture, and clear skies will most likely
allow fog/low stratus to spread east across NW PA and possible
into extreme NE OH during the pre-dawn and early morning hours.
Patchy to areas of dense fog are possible so can`t rule out a
Special Weather Statement and/or Dense Fog Advisory for few
hours this morning. Any fog should lift by mid- morning.

Low pressure will track across lower Michigan this afternoon into
this evening, lifting a warm front into the CWA with a cold front
entering the CWA from the west tonight. PoPs increase this evening
into tonight, although there may be quite a bit of dry air at the
surface so precip may struggle to reach the surface at the onset.
Most locations will likely see at least a brief period of showers
and possibly thunderstorms overnight into early Monday. As stated in
previous discussions, the frontal passage will be diurnally
unfavorable so the severe weather risk is low. The low and cold
front will slow over the eastern half of the area Monday, resulting
in continued shower and thunderstorm chances through the remainder
of the near term period.

Despite this system delivering the first widespread rain chances to
the CWA in quite some time, it certainty won`t be a drought-buster;
QPF through early Monday evening is under half an inch.

Today will be the last hot day for the foreseeable future with highs
in the 80s anticipated. A few spots west of I-71 might even touch 90
degrees this afternoon. Tonight`s lows will be in the low to mid
60s. A cooler but more seasonable temperature pattern develops
for Monday with highs only reaching the low to mid 70s.
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&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
The short term forecast period continues to signal the most
sustained period with rainfall all month. Unfortunately, the rain
during the period will not be a drought buster, but will at least
curb the drought from getting substantially worse for at bit. Rain
will be scattered in coverage on Monday night, as a front will
straddle the forecast area with some energy approaching from the
west. The main rain show will be on Tuesday as the main
shortwave trough approaches aloft and a low pressure system
lifts northeast along the front and through the forecast area.
Have a large area of categorical PoPs at some point on Tuesday
or Tuesday night. The evolution of the main upper trough across
the Great Lakes region is slower this morning and it appears the
the main trough axis won`t enter the local area until Wednesday
evening, as the energy of this feature splits east and south.
Until this feature escorts the final cold front through the
area, there will be some residual rain chances on Wednesday,
especially east. Temperatures through the period appear to be
back toward seasonal averages in the 70s.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
There remains fairly low confidence in the late week forecast, given
several closed upper low features across the eastern two-thirds of
the United States with large spread in placement depending on the
extended guidance member. While the entire forecast period has just
marginally higher PoPs (into the 20% range) due to the range of
guidance and a slower progression of the eastern low that has
increased rain chances for Wednesday, as mentioned above, believe
that most of the forecast period will likely end up being dry. An
upper ridge will eventually emerge across the region and allow for
dry and seasonable conditions. Toward the weekend, there will be
some monitoring for potential impacts to the synoptic pattern due to
a potential tropical system in the Gulf of Mexico.

&&

.AVIATION /12Z Sunday THROUGH Thursday/...
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A brief period of non-VFR in fog/low stratus is possible at KYNG
for the first couple of hours of the TAF period. Otherwise, VFR
will persist until showers begin to move east into the area this
evening and spread east across the CWA overnight. Ceilings and
visibilities may struggle to deteriorate at the onset due to low
level dry air, but ceilings should drop to at least MVFR after a
few hours. Some guidance is hinting at IFR conditions late in
the period, but would like to see how upstream observations
trend before introducing to the TAFs. A few rumbles of thunder
can`t be ruled out tonight, but any thunderstorms would be
isolated since precipitation will be moving into the area during
a diurnally unfavorable timeframe.

Winds will be light and variable or out of the south at 5 knots
or less before becoming south/southwesterly and increasing to 5
to 10 knots at western terminals during the afternoon and
eastern terminals this evening. A lake breeze will produce
northeast winds 5 to 10 knots at KERI/KCLE this afternoon into
early this evening.

Outlook...Non-VFR possible in scattered showers and
thunderstorms and low ceilings Monday. Non- VFR likely Monday
night through Tuesday in showers and thunderstorms and low
ceilings. Non-VFR conditions may linger through Wednesday.
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&&

.MARINE...
A ridge rebuilding into the region today will support offshore flow
before easterly winds and a push of onshore northeasterly winds
develop for the late afternoon and evening. For tonight, a cold
front will approach the lake from the west and offshore flow will
return. There will be a window with 10 to 15 knot winds over the
eastern portion of the lake late tonight into Monday. The front will
cross the lake by Monday afternoon but will retrograde west on
Monday night as a low pressure system will move northeast along the
front for Tuesday. North to northwest flow will be favored behind
the front and the low and southerly flow will be favored east of the
front and southeast of the low. The low will pull the front fully
across the lake for Wednesday and westerly flow will build and some
higher waves are possible in the eastern and central basins. High
pressure will build into the region and allow for northeast flow for
Thursday and Friday. Overall, the probability for a marine headline
is low but there will be periods of unpleasant conditions with 2 to
3 ft waves and rain chances early in the week.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
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OH...None.
PA...Dense Fog Advisory until 9 AM EDT this morning for PAZ002-003.
MARINE...None.
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&&

$$

SYNOPSIS...Maines
NEAR TERM...Maines
SHORT TERM...Sefcovic
LONG TERM...Sefcovic
AVIATION...Maines
MARINE...Sefcovic