Scientific Forecaster Discussion
fxus61 Kiln 181034
Area forecast discussion
National Weather Service Wilmington Ohio
634 am EDT Wed Oct 18 2017
high pressure will keep dry air and mainly clear skies over the
region through the week. Temperatures will gradually warm as
the high moves slowly east.
Near term /until 6 PM this evening/...
surface high pressure will extend from the mid Atlantic back
into the Ohio Valley today. Skies will be mainly clear.
Temperatures early this morning will drop into the mid 30s to
the lower 40s. Some patchy frost is still possible. Also, some
River Valley fog is expected for southern river valleys through
Under abundant sunshine and a southerly flow, highs will warm
into the upper 60s and lower 70s this afternoon.
Short term /6 PM this evening through 6 PM Thursday/...
the surface ridge axis will shift a little east tonight into
Thursday as a dry cold front pushes east/southeast into the
Great Lakes. Again, only a few cirrus is expected, with perhaps
a few-scattered cumulus clouds developing along ahead of the frontal
boundary in our far northwest late in the day Thursday.
After a warmer day and a little more pressure gradient, lows
tonight should range from the lower 40s in the low
lying/sheltered locations to the upper 40s across higher terrain
and our northwest zones. On Thursday, southwest to west winds
ahead of the front along with sunshine will boost highs into the
Long term /Thursday night through Tuesday/...
under an amplifying mid-level ridge over the eastern half of the
conus, a sprawling area of very dry surface high pressure will be
moving slowly east on Thursday night, still maintaining control of
the weather situation over the Ohio Valley for another couple days.
Aside from a very weak cold front stalling out (and then returning
north) in the Northern Ohio valley on Thursday night into Friday,
there will be little change in the overall pattern through Friday
night. Low-level warm advection, with gradually increasing 925mb
temps, will allow for Friday to be slightly warmer than Thursday.
As confidence has increased in a more amplified pattern on Saturday,
with deep-layer flow becoming more southerly over the Ohio Valley,
there is greater confidence as well in temperatures being warm for
the first day of the weekend. If the forecast for Max temps in the
middle to upper 70s verifies, it will be about ten degrees above
normal. This looks to be the warmest day of the entire forecast
On Sunday, a sharp but narrow trough will begin its progression
eastward across the Mississippi Valley, eventually reaching the Ohio
Valley at some point between then and Monday. Model timing agreement
remains somewhat sub-par with this system, and the differences are
primarily focused around the interaction between the southern end of
the trough (which may form a cut-off low) and the strong jet stream
pushing east across the northern tier of states. Unfortunately, this
time frame remains in an unstable part of the forecast cycle, with
GFS/European model (ecmwf) run-to-run consistency performing poorly.
With the above in mind, pops will be kept in the chance range until
this really gets locked in a little better. As of now, the greatest
precipitation chances appear to be during the Sunday night forecast
period, possibly continuing into Monday. Once the trough and its
associated cold front pass through the area, there appears to be
potential for a larger upper trough to move into the Great Lakes
late on Monday and into Tuesday, which should provide two things --
much cooler temperatures and continued chances for rain.
Aviation /12z Wednesday through Sunday/...
surface high pressure will extend across the Ohio Valley
through the taf period.
For early this morning, River Valley fog will once again be a
concern at kluk. Fog should burn off by 14z.
Otherwise, mainly clear skies are expected through the period.
Winds will increase from the south between 5 and 10 knots by 16z
then diminish after 23z.
Outlook...no significant weather expected.