Area Forecast Discussion
Issued by NWS Wilmington, OH-- Highlight Changed Discussion --
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FXUS61 KILN 211722
Area Forecast Discussion
National Weather Service Wilmington OH
122 PM EDT Wed Sep 21 2016
High pressure will remain over the Ohio Valley through the rest of
the work week, allowing dry weather to continue. Temperatures will
remain above normal through Friday with highs in the mid to upper
80s. A cold front will drop south from the Great Lakes Friday
night into Saturday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Showers and thunderstorms dropping southeast across southern Lake
Michigan are forecast to dissipate as they move into the more
stable and drier airmass across our region. The net result for our
forecast area may just be a few higher level debris clouds making
it down into northwest portions of our fa. Still though, expect
mostly sunny skies across our area through this afternoon as high
pressure will remain in control. With a similar airmass as the
past few days, highs today will once again push up into the 85 to
90 degree range.
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
The surface high will slide off to the northeast for the end of
the work week, with southerly return flow starting to draw
slightly warmer and more humid air into the region Thursday into
Friday. Surface dew points will rise back into the low to mid 60s,
but forecast soundings show a pretty dry lower atmosphere. Expect
a gradual increase in high/mid level clouds stemming from a cold
front situated over lower Michigan. While there will not be any
appreciable change in airmass over the region, Thursday`s 850 mb
temperatures will warm slightly to around 18 degrees C. This will
translate into upper 80s for highs across most of the ILN forecast
area, with some southern locations very close to 90. These
readings will be 10 to 15 degrees warmer than normal for this time
Thursday night into Friday the ridge over the Ohio Valley erodes
as a mid level ridge becomes more amplified over the Plains. A
weak shortwave will ripple through the region but low level
moisture will be limited with PWATs just over an inch, so have
maintained a dry forecast. Temperatures will remain above normal,
as a cold front over the Great Lakes region will not drop into the
forecast area until late Friday into Saturday.
.LONG TERM /SATURDAY THROUGH TUESDAY/...
Mid level ridging will shift slowly east across the Mississippi
Valley toward the Ohio Valley through the weekend. There are some
model differences as to its strength though and just how quickly
it will push east Saturday into Sunday. As a result, there are
also some discrepancies in the timing and placement of some weak
pieces of energy pushing over the top of the ridge and possibly
affecting northern/eastern portions of our area on Saturday.
Given the uncertainty, weak forcing and relatively dry airmass,
will keep the forecast dry through the weekend. Temperatures for
Saturday will remain above normal with highs in the 80s.
There are some significant model differences through the first part
of next week. The 12Z GFS is breaking down the ridge Sunday into
Monday as some short wave energy drops down across the Great Lakes,
helping to push a cold front through our area Monday into Monday
night. Meanwhile, the 12Z CMC keeps a high amplitude ridge in place
across the region through Monday. The 12Z ECMWF is more of a
compromise, keeping the ridge in place through Monday before
allowing for a front to approach from the northwest on Tuesday. Will
trend the forecast more toward the middle of the road ECMWF,
allowing for some slight chance pops to work in from the northwest
Monday into Tuesday. Temperatures are tricky through the end of the
long term, depending an the strength of the ridge and timing of the
possible front. Will generally hedge and go with a model blend, with
highs in the 70s to possible low 80s through early next week.
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --High pressure will remain in control of the weather through the
TAF period. We may see some occasional spotty cirrus drift down
from the convection well off to our northwest but for the most
part expect mainly clear conditions into Thursday. With a light
easterly surface flow, expect fog and low visibilities to develop
at KLUK once again tonight into early Thursday. Otherwise, VFR
conditions will prevail through the period.
OUTLOOK...No significant weather expected.
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