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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KILN 071858
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
258 PM EDT Fri Aug 7 2020

.SYNOPSIS...
High pressure in the lower Great Lakes will slowly track
southeast into the Ohio Valley on Saturday. The high will linger
through Monday as it reaches the Appalachians and becomes more
diffuse. Southwest flow will then take over and a threat for
showers exists late Monday and overnight, with a better chance
for rain expected Tuesday as an upper low takes shape over the
Midwest.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Expect any lingering cloud cover this afternoon to be wiped out
by nightfall with generally clear skies found overnight.

Towards daybreak, some patchy ground fog could be present in
low-lying and fog-prone areas, but is not expected to be of any
significance or reduce visibilities in most locations.

With the light/variable winds, and clear skies, lows will drop
into the mid to upper 50s, with a few lower 60s possible in the
southeast.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
Surface high pressure will remain overhead through the day on
Saturday and slide southeast overnight. This will provide for
dry conditions and a gradual warming trend as the flow
eventually shifts to the south-southwest. Highs on Saturday
will be within 2-3 degrees of 85, warmest in the southeast and
coolest in the northwest. Overnight lows with a light surface
wind and maybe some cirrus will bottom out right around 60 for
most locales.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
High pressure is forecast over the Central Appalachians/Upper
Ohio Valley as the extended period begins. H5 ridge looks like
it will try to build back into the eastern Great Lakes on Sunday
in the wake of a parting s/w. Although the low level flow
becomes southerly on the backside of the departing high,
dewpoints only start to rebound in Indiana on Sunday. Will keep
Sunday dry as it looks like convection will stay just to the
west. Highs will increase a little more, ranging from the mid to
upper 80s in the Whitewater Valley/West Central Ohio to the
lower 90s in the lower Scioto Valley/northeast Kentucky.

Sunday night into Monday, a closed H5 low will drop out of the
Canadian Rockies into the Canadian plains. A cold front
associated with the H5 low is forecast to push into the western
Great Lakes on Monday. This will add surface forcing and should
help with scattered thunderstorm development. Highs will remain
above normal.

Tuesday into Wednesday, the region will be on the southern edge
of zonal flow over the Great Lakes. This will allow some upper
level forcing to affect the region, which will prompt diurnal
convective development. Above normal highs in the mid 80s to
lower 90s are forecast.

For the last part of the week, models diverge in the handling
of the H5 flow. All the extended models try to build a ridge,
but they leave some weakness over the Ohio Valley. There should
be enough low level instability and upper support to continue
diurnal convection both Thursday and Friday.
-- End Changed Discussion --

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Very light flow will be found as high pressure slowly builds
into the region from lower Michigan. Fair weather cu is
expected to be the primary result of this system, and some
shallow ground fog could occur towards daybreak at KLUK.

OUTLOOK...Thunderstorms are possible on Monday and Tuesday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.

&&

$$
SYNOPSIS...Franks
NEAR TERM...Franks
SHORT TERM...Franks
LONG TERM...Sites
AVIATION...Franks