Area Forecast Discussion
Issued by NWS Wilmington, OH-- Highlight Changed Discussion --
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FXUS61 KILN 221744
Area Forecast Discussion
National Weather Service Wilmington OH
144 PM EDT Sat Apr 22 2017
As an area of upper level low pressure moves into the
southeastern states, cool conditions are expected over the Ohio
Valley today, warming slightly on Sunday. A continued warming
trend is expected going into the new week, with drier and
sunnier conditions on Monday and Tuesday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
An initial wave of pcpn is affecting primarily our far southern
areas this morning. This will continue to shift off to the east
through late morning, leading to a break in the pcpn across our
south. However, another wave of pcpn is pushing quickly east
across southern Illinois and southern Indiana attm and this is
forecast to move back into across our southern areas for later
this morning and into this afternoon. The latest HRRR may be
struggling somewhat with how to handle this second wave though.
Some light returns are showing up quite a bit farther north
across central Illinois and into central Indiana than what is
being forecast. A lot of this is probably not reaching the
ground but suppose a few sprinkles cannot be ruled out. As a
result, will allow for chance pops to spread back into our
southern areas and linger a 20 pop a little farther north to
account for some of these weaker returns. Temperatures will
likely only rebound a few degrees today in continued cool
northeasterly low level flow.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
Elongated surface high pressure is expected to position itself
from Iowa to Lake Erie tonight, as surface low pressure begins
to develop in the deep south. A gradient will thus exist between
very different air masses -- warmer and wetter in the southern
Appalachians, and cool and dry in the northern Ohio Valley and
southern Great Lakes. Outside of the chance of a few light
showers in the far southern ILN CWA, most of the forecast area
should be well within the drier air mass, with clearing skies
tonight. Persistent NE flow will keep radiational cooling
conditions from becoming ideal, limiting the chances for frost,
even as temperatures may get close to 40 degrees by Sunday
This pattern will change very little on Sunday, as the main
driver of the scenario -- the mid-level low in the southeastern
states -- will not be moving very fast. By Sunday afternoon,
there may be just enough 850mb-700mb moisture wrapping NW/W into
the forecast area to allow for a few showers in the southeastern
third of the CWA. That will present another day with an unusual
temperature gradient, as temperatures will likely be warmest in
the NW CWA, where mostly clear conditions are expected.
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Upper level low will slowly move southeast from the Tennessee River
Valley to the southeast United States coastline Sunday night into
Monday. As this occurs, the threat for showers will end across the
southeast CWFA while clearing takes place there as well. More
sunshine and airmass modification will boost temperatures into the
upper 60s to the lower 70s on Monday, which isn`t too far from
For the period Monday night into Tuesday, upper level low will push
northeast near the coastline of the Carolinas. We will see weak high
pressure across our region. With another day of airmass modification
and developing southerly flow, highs will warm into the mid and
For the period Tuesday night into Wednesday night, weak ridging
shifts east, along a frontal system to push east/southeast through
the region. This will bring the next chance of showers and
Thursday may end up being dry in the wake of the front. However, the
frontal boundary is expected to lift north as a warm front Thursday
night into Friday as upper level flow begins to amplify. This will
bring another chance of showers and thunderstorms, particularly for
Discrepancies occur in the long range models as we head into Friday.
The ECMWF wants to push another frontal system into the region while
the GFS dries the Ohio Valley out in the wake of the warm front. It
does not bring the next frontal system into the region until next
Saturday. Have decided to keep forecast dry given stark differences.
Temperatures will be warm by the end of the week with lower to mid
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --The second wave of pcpn is continuing to overspread southern
portions of our fa but much of it does not seem to be reaching
the ground. As a result, will continue with just some VCSH
coverage in the first few hours of the TAFS for KLUK/KCVG. Cigs
are primarily VFR although we have seen some brief periods of
MVFR from time to time and this will continue to be possible
through at least mid afternoon. Otherwise, the models continue
to trend farther south with additional pcpn later tonight and
into the day on Sunday. Will keep the TAFs dry through the
remainder of the period with VFR conditions expected.
OUTLOOK...No significant weather expected.
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