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000
FXUS61 KCLE 142339
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
739 PM EDT Mon Aug 14 2017

.SYNOPSIS...
A weak cold front will move across the Eastern Lakes Tuesday then
lift north as a warm front by Wednesday night. Low pressure will
track into the Central Great Lakes region Thursday night forcing a
cold front across the forecast area.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Increasing clouds overnight ahead of weak front that will move
across the forecast area tomorrow.  Tonight should remain dry with
temps a couple of degrees above this mornings lows.

Quick update to alter sky grids, reducing current coverage and
slowing the arrival of the thicker more opaque cloud cover.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
Weak front will push across the forecast area tomorrow afternoon but
then lift north as a warm front tomorrow night.

Frontal boundary will likely be stalled over our southern counties
on Wednesday morning as high pressure builds over the Central Great
Lakes. This position is farther south than previous runs which
should reduce the chances of showers and thunderstorms during the
afternoon. The ridge strengthens aloft and warm mid-levels should be
sufficient to keep most of the area capped. By late in the day,
winds near the boundary will veer around to the southeast as a warm
front develops and starts to lift back north. Best chances for a
stray shower or thunderstorm will be across the southern counties or
NW Ohio. Lowered highs by a couple degrees given the northerly flow
off the lake.

Theta-e advection increases through the column on Wednesday night
and could be enough to kick off a few showers or thunderstorms. By
Thursday we will be in the moist warm sector ahead of low pressure
deepening over the central Great Lakes. Energy lifting out of the
trough could kick off thunderstorms at any point with the best
forcing during the late afternoon and early evening ahead of the
approaching cold front. Expecting skies to be mostly cloudy but any
breaks will allow for instability to increase quickly. Current
forecast handles this well and raised pops about another 10 percent
in some areas. Based on timing of the front, raised pops in eastern
areas to likely for the first part of Thursday night and lowered in
the west behind the front late Thursday night.

Deeper moisture exits to the east on Friday but enough residual low
level moisture may linger in the east to kick off a few showers or
thunderstorms. Will continue with a low chance pop as one more
shortwave moves through the flow aloft on Friday afternoon.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Cold front looks like it will be east of the region Friday night.
However there could be a few showers off of Lake Erie as some cooler
air spills across it. These showers should be scattered at best
across NE OH/NW PA.  A stronger upper level trough arrives Saturday
afternoon into Saturday night but the low levels will not be all
that moist. So the coverage of any thunderstorms will be limited.
Will continue to keep so low POPS in the forecast.

Temperatures through the long term should be very close to seasonal
averages.

&&

.AVIATION /00Z Tuesday THROUGH Saturday/...
Weak system near Chicago this evening will move across the
terminals Tuesday with a small threat of thunderstorms during
the day. Chances are under 30 percent and no mention in the TAFs
at this time. Light south winds shift to the west with front`s
passage. Small chance of early morning BR at a few sites with an
increase in surface dewpoints.

OUTLOOK...Patchy BR possible each morning. Areas of Non-VFR possible
Wednesday evening through Thursday with scattered storms.

&&

.MARINE...
Lake breezes early this evening will transition to a southerly wind
on the lake overnight ahead of a weak front approaching from the
west. Weak lake breezes may develop again Tuesday afternoon with
northeast winds increasing on the lake Tuesday night as the front
pushes south of the lake. Northeast winds of 10-15 knots Tuesday
night and Wednesday will make conditions a little choppy on the
western basin. The front will stall across central Ohio Wednesday
then lift back north as a warm front Wednesday night. Low pressure
from the upper midwest will track across the Great Lakes region on
Thursday, pulling a cold front across the lake late in the day.
Westerly winds increase to 15-20 knots behind the front on Friday
and Small Craft Advisories may be needed on the east half of the
lake. Conditions improve over the weekend as high pressure builds
overhead

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.

&&

$$
SYNOPSIS...DJB
NEAR TERM...DJB/Oudeman
SHORT TERM...DJB/KEC
LONG TERM...KEC/Mullen
AVIATION...Oudeman
MARINE...KEC