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fxus61 Kiln 221345 

Area forecast discussion
National Weather Service Wilmington Ohio
945 am EDT Tue Oct 22 2019

a cold front is working through the area early this morning
brings isolated showers and gusty winds. Cooler and blustery
conditions will occur on Tuesday as strong low pressure persists
over Ontario. High pressure over the middle Tennessee Valley
will build in on Wednesday, offering dry weather and near
seasonable temperatures. Southerly flow will bring warmer
temperatures for Thursday.


Near term /through tonight/...
morning update was generally focused on exiting the rainfall in
far eastern sections of the County Warning Area within the next hour. Clearing
is noted between the departing cloud deck associated with the
frontal passage and lingering rain to the east and the cold air
stratus to the northwest. This stratus will lobe southward into
the County Warning Area this afternoon, primarily over northern sections. 800 mb
temperatures drop across the County Warning Area today and then rise overnight
as the axis of the cold air tracks ENE and away, leading to
clearing skies by daybreak. Tweaked temperatures and dewpoints
but overall changes in this regard were superfluous. Previous
discussion still germane for today/tonight:

Mostly sunny skies to dominate the first half of the day before
cumulus begins to develop and spread, especially along and
north of I-70. Further south toward the Ohio River, more
abundant sunshine prevails as cold air advection is rather weak
with winds out of the southwest. With the center area of low
pressure slow to pull away into southeast Canada, blustery winds
are forecast once again today. Strongest winds occur along and
north of I-70 with winds gusting 30-35 mph at times. A few
isolated wind gusts to 40 mph are possible. South of I-70,
regular gusts of 20-25 mph are expected.

Overall, temperature advection is fairly neutral so temperatures
are forecast to rise into the low to mid 60s, especially along
the Ohio River. With cloud cover across the north, temperatures
may struggle a little but still think mid to upper 50s are
achievable today. Upper 30s and low 40s for most, but some mid
30s may be possible in sheltered areas.


Short term /Wednesday through Wednesday night/...
fairly benign Wednesday as surface high pressure builds over the
Tennessee Valley. Southwesterly flow and abundant sunshine helps
push temperatures a few degrees above normal as temps rise into
the mid and upper 60s. Nighttime low temperatures a few degrees
above normal with widespread mid 40s under clear skies.


Long term /Thursday through Monday/...
although not too much in the way of active weather is expected to
start the long term period, it is not expected to be entirely quiet
either as a moisture-starved cold front progresses through the Ohio
Valley during the day on Thursday. And with southwesterly surface
flow well-established early on Thursday, expect what will likely be
the warmest day in the long term fcst period for at least the
southeastern half or so of the iln forecast area as highs reach into the lower
70s for most of the ahead of the aforementioned front. Further to
the north/west, clouds may keep temps a bit cooler across portions
of west-central Ohio and east-central Indiana.

It is important to mention, however, that even at this point,
forecast confidence tails off fairly quickly beyond Thursday owing
to uncertainties in exactly how digging short wave energy across the south-
Central Plains evolves for the end of the week. The GFS continues to
show a wetter solution for Thursday night into the day on Friday
while the European model (ecmwf) remains persistent in its depiction of a cutoff low
in the desert SW by late in the workweek opposed to the more
progressive GFS scenario. The European model (ecmwf) solution would support a drier
Thursday night into Friday but perhaps a wetter weekend as the
aforementioned low eventually ejects into the Southern Plains and
Mississippi River valley by Saturday into Sunday. This particular
evolution would spell a fairly wet Saturday night through Monday
morning scenario for much of the Ohio Valley -- and there is some
support for this even in the eps (with ensemble mean quantitative precipitation forecast > 1" for a
large portion of the region in the Saturday night into Sunday night
time period). However, conversely, the gefs is on the other end of
the spectrum with ensemble mean of only a tenth of an inch or so for
most of the area during the Saturday-Monday time frame. This, of
course, leads to uncertainty into exactly how to handle the late
week forecast, and did not have confidence to go with a dry forecast
for this weekend and handled the uncertainty with high chance pops
for now. However, should the longer-range guidance begin to trend
toward a closed low/European model (ecmwf) scenario (with seems most plausible at
this juncture), pops and quantitative precipitation forecast may need to be further increased with
future fcst cycle updates.

No matter how the weather pattern evolves for the end of the long
term period, temperatures will be near to slightly below normal for
the end of the week into this upcoming weekend, with lows in the
upper 30s and 40s and highs mainly in the upper 50s and 60s.


Aviation /14z Tuesday through Saturday/...
the corridor of most widespread showers has moved east of even
kcmh and klck, although some 1500-2000ft cigs will remain
possible over the first several hours of the taf period for
these eastern sites. Elsewhere, expect a clear start to the day
but a fairly healthy VFR cu field should develop past 15z or so
-- especially for kday, kcmh, klck, and Kiln where broken cloud
cover is likely by the afternoon.

The main item of interest for the taf period will be the gusty
winds, with sustained west-southwesterly winds of 15-18kts and
gusts approaching 30kts by early this afternoon. And while the
winds should subside past sunset, the gradient will not
completely relax so anticipate winds of 10-12kts with
occasional gustiness to 18kts possible through 06z before
diminishing a bit toward the end of the period.

The cu/stratocu field that is expected to develop this afternoon
will be a bit slow to push east this evening but should
eventually yield to clear skies past 06z everywhere (earliest
for kcvg and kluk in the evening).

Outlook...MVFR conditions possible again on Friday with the
next cold front.


Iln watches/warnings/advisories...



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