Area Forecast Discussion
Issued by NWS Wilmington, OH-- Remove Highlighting --
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FXUS61 KILN 281755
Area Forecast Discussion
National Weather Service Wilmington OH
155 PM EDT Fri Oct 28 2016
High pressure centered over the Ohio Valley this morning will
slowly move toward the southeast U.S. coast by Saturday evening.
Return flow around the high will allow temperatures to climb to
much above normal by Saturday. A cold front is then expected to
push south across the Great Lakes Sunday into Sunday night. This
front will bring a chance of precipitation, mainly on Sunday. High
pressure will move east across the Great Lakes on Monday, while
the old frontal boundary moves back northeast as a warm front.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Surface high pressure will slowly push off to the east through
this afternoon. This will allow for some mainly high level clouds
to continue to drift down from the northwest through the day.
Highs will range from near 60 degrees in the northeast to the
upper 60s in the southwest.
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
The majority of operational models are in fairly decent agreement
in terms of synoptic scale systems through the short term. The NAM
was showing its usual low level moisture bias developing across
the northwest late tonight into Saturday. Otherwise, a blend of
the NAM/GFS/ECMWF was used through Saturday night, then a
GFS/ECMWF blend Sunday into Monday night.
Surface high pressure will slowly move to a position off the
southeast U.S. coast by Saturday night while a cold front slowly
works its way into the Great Lakes. The scenario will bring an
increase in the surface pressure gradient along with fairly
strong WAA in association with southwesterly return flow. Under
partly to mostly sunny skies, along with with some breezy
conditions across the northwest half, temperatures will climb to
much above normal readings on Saturday. Highs will range from the
mid 70s north to near 80 along and south of the Ohio River. Record
highs at the big three sites are all in the 80s, and appear safe
at this time, despite temperatures some 15 degrees above normal.
For Saturday night into Sunday, the cold front will gradually move
southeast into our area. This process will bring an increase in
clouds, along with the threat for precipitation. Low level forcing
and upper level support will be maximized across the northern
zones during the day. Forcing will quickly wane by Sunday evening
as s/wv energy aloft will exit to the east. Thus, will have high
chance PoPs across the north on Sunday with low chance to no
threat for showers across the far southern zones. Precipitation is
expected to be in the form of convective showers. Instability
parameters indicate that there could be a rumble of thunder
during the afternoon near the frontal zone, so have added a slight
chance of thunder. Temperatures will show a small diurnal rise
across the northwest due to the faster arrival of the front, while
locations farther to the southeast should be able to warm up into
For Sunday night, models indicate that the threat for
precipitation will end fairly quickly during the early evening.
However, low level rh fields show fairly abundant moisture at 925
mb and 850 mb such that mostly cloudy skies will likely continue
into the overnight hours. Lows by Monday morning will range from
the mid 40s north to the mid 50s south.
For the period Monday into Monday night, mid level ridging will
move east across the Great Lakes and Ohio Valley. This will allow
the old frontal boundary to move back northeast as a warm front
through this period. Considerable clouds Monday morning should
give way to partly cloudy conditions by Monday evening, followed
by skies becoming mostly clear Monday night. Highs will range from
the lower 60s northeast to the lower 70s along and south of the
Ohio River on Monday. Lows Monday night will remain in the 50s.
.LONG TERM /TUESDAY THROUGH THURSDAY/...
Southerly flow will become more prominent on Tuesday. Tuesday is
expected to be quite warm once again with decent southerly flow
and ample sunshine. Temperatures will be well above normal with
highs in the middle 70s to around 80.
Models start to diverge for Wednesday into Thursday with timing and
strength of fronts. At this time there is a better signal for
Thursday therefore went dry on Wednesday and bring in a chance for
rain showers on Thursday. Even with the potential front expect
continued above normal temperatures through the long term.
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --Surface high pressure will slide off to the east tonight as a cold
front sags slowly southeast into the southern Great Lakes through
the day on Saturday. With a dry airmass in place, expect mainly
just cirrus to affect the TAFS through the period. A strengthening
low level jet later tonight will lead to some marginal LLWS
criteria late tonight into early Saturday morning. After that, as
the surface pressure gradient increases from the northwest,
expect southwest winds to increase with gusts into the 20-25 knot
range toward the end of the TAF period.
OUTLOOK...MVFR ceilings are possible on Sunday and Monday.
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