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fxus61 Kiln 171444 

Area forecast discussion
National Weather Service Wilmington Ohio
944 am EST sun Nov 17 2019

high pressure will extend across the region today keeping the
area dry and cool. An upper level system will swing across the
region Monday into Tuesday, offering an increase in clouds.
Temperatures will increase to near normal levels by mid week as
upper level ridging builds into the Great Lakes and the Ohio
Valley. The next good chance for rain will occur Thursday ahead
of an approaching frontal system.


Near term /until 6 PM this evening/...
southerly low level flow around sfc high pressure over New
England to develop today. Mid level flow will back
southwesterly as a trof over the plains moves into the mid
Mississippi Valley.

High clouds will spill into the area increasing from west to
east this afternoon. Temperatures will warm some, but will
still be around 5 degrees below normal. Highs are fcst to
range from the lower 40s in the northwest to the lower 50s for
the southeast.


Short term /6 PM this evening through 6 PM Monday/...
the 500 mb trof will swing up the Ohio Valley tonight. Models
continue to struggle with timing and placement, if any, of
precipitation tonight. Due to lack of deep moisture will
continue the trend and will only bring in an increase in
clouds. Forecast lows tonight are expected to be in the lower

On Monday the 500 mb energy cuts off a weak upper low as the trof
GOES slightly negatively tilted. Moisture remains limited so
confidence isn't high enough to add mention of light pcpn in at
this time. Cloud cover will keep high between 45-50 degrees.


Long term /Monday night through Saturday/...
on Monday evening, broad longwave troughing will be well
established across the eastern half of the Continental U.S.. the first of a
couple of weak shortwave troughs will already be east of the
Ohio Valley, with another weak shortwave expected to move
southeast into the area by Tuesday morning. The surface pattern
over the Ohio Valley will be rather nebulous, so there are no
signs of strong forcing through Monday and Tuesday. As model
consistency has begun to finally improve somewhat for this time
period, confidence has also improved that measurable
precipitation will be fairly unlikely. Pops will be kept out of
the forecast with this update, but there is one item Worth
mentioning -- the thick low-level moisture expected to develop
on Monday night and Tuesday. Any weak lift could eventually
produce some drizzle, if stratus is able to develop as currently
expected. This may need to be added in future forecast updates.

A brief period of ridging is expected on Wednesday and early
Thursday, in advance of what both GFS/European model (ecmwf) solutions are
advertising as a fairly well-defined trough and associated cold
front later on Thursday / Thursday night. Both models are now fairly
consistently depicting a surface low moving northeast through
southern Wisconsin early on Thursday, though they differ in
strength, with the GFS (as it has been) producing a more amplified
and deeper overall solution. Nonetheless, as confidence has
continued to increase in the overall timing/arrangement of
precipitation, pops have further been increased into the 60-80
percent range. The highest pops are focused just ahead of the cold
front, primarily on Thursday afternoon and early evening. Even in
the solutions with a more potent surface low (and thus more potent
warm advection) it does not appear that instability will be present,
so thunder will be kept out of the forecast again. A quick drying is
expected on Friday morning behind the front, before a developing
wave in the southern stream brings additional precipitation across
the southeastern states on Saturday -- with at least some potential
to spread as far north as Ohio.

Significant warming is expected in the Tue-Wed-Thu time frame, with
Tuesday still coming in below normal (lower to upper 40s) and
Wednesday ending up near normal (lower to mid 50s). Temperatures
were again increased in the warm advection on Thursday, with
expectations of reaching the middle to upper 50s. Based on current
projections for the front, Thursday may end up with a roughly
diurnal curve in terms of timing, even if advection is the dominant
contributor to temps. Friday and Saturday should only make it to the
40s behind the cold front.

A final note about winds on Thursday -- as model projections have
continued to show a strong gradient associated with the surface low,
wind speed projections have also increased over the Ohio Valley.
Gusts to around 30 miles per hour have been included in the forecast for now,
but this is still for an event out on day 5 of the forecast cycle.
As the event gets closer, this could be increased further.&&

Aviation /09z Sunday through Thursday/...
area of broken cirrus that affected the tafs during the evening
is shifting to the east and will will leave clear skies for the
rest of the night.

Light winds associated with high pressure are allowing some fog
development in the river valleys. Luk has already seen some
MVFR/IFR fog. Expect the fog to affect luk through sunrise, with
some MVFR fog also possible at cvg and iln.

Later today high clouds will increase from the west ahead of a
500 mb trof. Surface winds will veer from east to south during the
day around 5 knots.

Outlook...MVFR ceilings possible Monday night into Tuesday. MVFR
ceilings and visibilities possible Thursday.


Aviation /15z Sunday through Thursday/...
high level moisture is already beginning to work back into the
tafs early this morning. Based on satellite, it looks like the
initial shot will be broken across the nrn tafs, but then it will
become scattered later this morning.

Fog has not been as widespread as thought earlier. Luk saw fog
earlier this morning, but it is looking like it as already moved
away from the Airport.

Later this afternoon the high clouds will increase again from
the west ahead of a 500 mb trof. By 00z, clouds will lower to a mid
deck for the overnight hours.

Outlook...MVFR ceilings possible Monday night into Tuesday. MVFR
ceilings and visibilities possible Thursday.


Iln watches/warnings/advisories...



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