Area Forecast Discussion
Issued by NWS Wilmington, OH-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KILN 251409
Area Forecast Discussion
National Weather Service Wilmington OH
1009 AM EDT THU AUG 25 2016
Warm and humid conditions will persist today, with mid-level ridging
centered over the southeastern states. There will be chances for
showers and storms on occasion, with a weak frontal boundary located
in the northern Ohio Valley. This front will move south through the
region into Friday, bringing slightly drier conditions going into
the weekend. However, temperatures are expected to remain above
normal into next week.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Morning convection in the northern counties has quickly
dissipated. There is still a fair bit of low cloud cover across
the area. It will take some time for this to break up and start to
lift. But once it does there is some potential for isolated storms
to develop across southern counties this afternoon. Lack of shear
in the south should just result in some localized heavy rainfall.
Better chance for storms appears to be in northern parts of
Indiana and Ohio. A front will be sagging into the area and a band
of higher shear will be in place. These storms may get into far
northern counties late in the afternoon and given the parameters
may pose a severe weather risk /straight line wind and tornado/ as
well as a heavy rain risk.
With dew points in the mid 70s...temperatures will not have to
warm much above yesterdays readings to get heat indices
approaching 100. At this point it still appears that this will
fall just short of heat advisory criterion.
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
After any remaining convection dissipates during the overnight
hours on Thursday, dry conditions are expected through the rest of
the short term. The cold front moving into the area will be
ushering in a slightly drier air mass, but the front is expected
to be severely lacking in forcing and convergence. With surface
high pressure moving into the southern Great Lakes on Friday, then
sliding east on Saturday, moisture and convective chances should
remain on the southern and western periphery of the Ohio Valley.
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
High pressure will exit the region Saturday and surface easterly
flow will turn southerly. Cloud cover from convection in the
midwest spill into the Ohio Valley. A surface boundary is expected
to lay out over the region early Sunday as high pressure builds in
the Upper Midwest. This should just provide a modest increase in
diurnal thunderstorm activity chances Sunday with a little more
increase on Monday, both with subsequent nighttime drops in these
Northeast flow on Monday into Tuesday night is expected as the high
traverses the Great Lakes region. Another repeat of increased
chances of afternoon thunderstorms is expected Tuesday and Wednesday
given what will become a nebulous surface pattern.
While all of the potential precipitation may not contain thunder,
have not tried to minimize the morning and evening chances by
calling them showers, even though this may be how the pattern
materializes. Just peppered any precip chances in the extended as
With a large and slow moving high in the upper atmosphere centered
from the Central Appalachians to the Mid-Atlantic coast, and with
mainly warm advection in the lower levels, a return to mid-summer
heat is indicated. High temperatures ranging from the mid 80s to the
low 90s will couple with dew points near 70 to make increasingly
uncomfortable air to the region. Some lower 80s temperatures may be
expected in areas where precip develops and skies remain cloudy all
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
Areas of stratus drifting across the region will impact the
terminals over the next several hours. Many locations will be
below 2000 ft before lifting and then scattering. So it appears
that the entire area may not become VFR until close to 18Z.
Otherwise, for later today, a weak cold front will approach the
region by late in the day. Latest model guidance, including high
resolution/convection allowing models, indicate that the region
should stay dry before the cold front starts to sag into northern
Indiana and northern Ohio between 21Z and 00Z. Latest runs are not
conclusive on the coverage of shower/storm potential and whether
they will form at all. Even if they do form, it looks like they
will weaken, perhaps dissipate before making it as far south as
the northern terminals. As a result, will maintain a dry forecast.
For the overnight period, the weak cold front will make its way
south toward the Ohio River. Winds will shift to the north. Some
river fog may develop near KLUK before the front passes. Have
placed MVFR/IFR visibilities for this potential.
OUTLOOK...Thunderstorms possible Monday.