Area Forecast Discussion
Issued by NWS Wilmington, OH-- Remove Highlighting --
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FXUS61 KILN 201042
Area Forecast Discussion
National Weather Service Wilmington OH
642 AM EDT SAT AUG 20 2016
Warm and humid conditions, along with the threat for showers and
thunderstorms, will persist until a cold front moves through the
area tonight. High pressure will then settle into the Ohio Valley
for the beginning of the week, bringing dry and cooler weather.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Operational models are in better agreement today in terms of
timing and strength of synoptic scale systems through tonight.
Have used a combination of these, along with high resolution/convection
allowing models, to ascertain coverage and timing of anticipated
showers and thunderstorms.
For today, embedded s/wv over the north central plains will dig
east, then northeast toward the western Great Lakes by this
evening. As this occurs, surface low pressure will deepen and
track toward the western Great Lakes as well. This will allow a
cold front to approach the region from the west. Ahead of the main
front, deep moisture will push northward. Models suggest that
scattered showers/storms will develop ahead of the main front from
late morning on as daytime heating and waa occur. By late in the
day, low level convergent flow/prefrontal trough will bring a
better chance of showers/storms, which should move into the CWFA
by late/early evening. Best chance for a strong or severe storm
is expected across the western CWFA where deep layer shear and
instability in combination will be the greatest. Main severe
weather threat would be strong and/or damaging wind. Also, can not
rule out some localized flooding in the more robust storms given
pwats of 2"+. Highs will range from the lower to mid 80s.
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
Deepening low pressure will pivot toward southern Ontario by
Sunday morning. Attendant cold front will move east through our
area tonight. Best chance for showers and thunderstorms will be
across the western CWFA this evening as prefrontal convergent flow
will be maximized, but likely Pops also look plausible in the east
based on latest high resolution/convection allowing models. High
resolution/convection allowing models also indicate that as the
night wears on, coverage of showers/storms should become more
scattered in nature as they head off toward the east. Precipitation
is expected to exit our eastern cwfa by sunrise. Cloudy skies will
show a clearing trend across the west late. Lows will range from
the upper 50s far northwest to near 70 far east/southeast.
Mid level trough will traverse east across the Great Lakes and
Ohio Valley on Sunday. Our region should be in the subsidence
region in the wake of departing low pressure with mainly caa
scattered to locally broken cumulus clouds expected. It will be
cooler and drier as dewpoints drop into the 50s. Highs will range
from 75 to 80.
For Sunday night, diurnal cumulus will decrease through the
evening, leaving mostly clear skies for the main overnight hours.
As high pressure builds into the Ohio Valley, winds will diminish.
Lows will bottom out in the mid to upper 50s.
High pressure will continue to influence the region Monday into
Tuesday night. Skies will be mostly sunny both days. Highs on
Monday will range from the upper 70s to near 80. Highs on Tuesday
will slightly modify to the lower 80s. Cool lows in the 50s will
continue for Monday night, with lower 60s expected Tuesday night.
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
Surface high pressure will move to the Atlantic seaboard on
Wednesday. Another day of dry weather is expected, although return
flow will bring an increase in dewpoints. Continued airmass
modification will result in highs in the lower to mid 80s.
A frontal boundary will approach the region Thursday into Friday
allowing for a chance of showers and thunderstorms across the
area. Due to model run to run inconsistencies limited
precipitation chances to the chance category at this time.
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --While widespread stratus has not developed over the TAF sites this
morning, patches of IFR/LIFR visibilities (with VV restrictions)
have occurred on occasion, especially for the southern TAF sites.
Some continued visibility and ceiling restrictions have been
included for the first few hours of the forecast.
SSW flow will increase this afternoon to around 10 knots, with
gusts possibly reaching as high as 20 knots. Chances for pop-up
showers and storms will increase by mid to late afternoon, with a
continued chance of storms through the evening, in advance of a
cold front moving into the region. Storms are fairly likely to
occur for all of the TAF sites, but the window for storm timing
remains somewhat large. Because of this, a VCTS with tempo SHRA
(and MVFR conditions) will be included for a few hours during the
most likely few hours. This can be updated to TSRA once timing and
impacts become more certain.
Precipitation will generally come to an end late tonight and early
into the overnight hours. A cold front will then move through the
region overnight, shifting winds to the WNW, and providing a few
gusts to around 20 knots. Some MVFR ceilings are also expected to
accompany the front.
OUTLOOK...MVFR ceilings may persist into Sunday morning.
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