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Area forecast discussion 
National Weather Service Wilmington Ohio
649 am EDT Friday Sep 19 2014

high pressure will extend from the Saint Lawrence valley to the
lower Ohio Valley today. The high will move off to the east on
Saturday as a cold front approaches the region from the northwest.
The cold front will push through the area Saturday night and
Sunday. High pressure will then become reestablished for much of
next week.


Near term /until 6 PM this evening/...
high pressure will extend from the Saint Lawrence valley to the
lower Ohio Valley today. Other than a few diurnal cumulus clouds
skies will be mainly sunny. Highs should be a couple of degrees
warmer than yesterday. Temperatures will generally range from the
lower to the upper 70s.


Short term /6 PM this evening through Monday night/...
operational NAM-WRF appears to be too slow with the upcoming
frontal system. Have sided with the faster European model (ecmwf)/GFS combination.

Surface high pressure will move off to the east tonight into
Saturday. Models indicate some low level moisture rotating NE into
our region late tonight into Saturday from the southwest. It is
difficult to know the coverage of clouds with this influx at this time so
have allowed skies to become partly cloudy toward morning across the
southern/southwestern County warning forecast area with other locations remaining mostly clear. On
Saturday...models hint that perhaps there could be enough
moisture/weak isentropic lift for a sprinkle/isolated shower with
aforementioned influx of low level moisture. Have kept the
forecast dry but this will have to be watched should trends
continue to hint at a small threat for light precipitation. Otherwise...skies
should stay partly cloudy for most of the day. Winds will increase
from the south/southwest well ahead of approaching cold front to
our northwest. With warmer 925mb/850 mb temperatures...we should
reach the upper 70s to the lower 80s for highs.

For Saturday night into Sunday...a cold front will push through
our region. Models indicate that the best instability...low level
frontal convergence...and upper support from a shortwave passing across
the southern Great Lakes will occur to our northwest Saturday
evening through early Sunday morning. As the front moves into our
region overnight into Sunday morning...instability will have waned
and low level frontal convergence will have weakened. As a
result...will keep probability of precipitation in the chance category for showers and
thunderstorms. It appears that the front may exit our southeast County warning forecast area by
early Sunday afternoon which should allow skies to become partly to
mostly sunny in its wake. Cold air advection in the wake of the front will bring
temperatures down a tad with highs ranging from the lower 70s
northwest to the upper 70s south/southeast.

For Sunday night into Monday...large scale upper level trough will
dig southeast into the eastern Great Lakes...New England...and the
middle Ohio Valley. An embedded shortwave will move through our area
during Sunday evening. However...moisture will be scant and any
spotty shower activity should remain to our north/northeast during
the evening. Skies are expected to become mostly clear for a good
part of the forecast area by Monday morning as surface high
pressure begins to build in from the northwest. Lows will range
from the middle 40s to the lower 50s. On Monday...the high will
continue to build east with skies becoming mainly sunny through
the day. Cold air advection in the northwest to northerly flow aloft will bring
lower temperatures despite a good deal of sunshine. Am expecting
highs to range from the lower 60s north to the upper 60s south.

A large area of high pressure will settle over the Ohio Valley
Monday night. Clear skies and cool temperatures in the lower to
middle 40s will result.


Long term /Tuesday through Thursday/...
high pressure will dominate the weather pattern through the long
term period. Dry weather along with a gradual warming trend is


Aviation /12z Friday through Tuesday/...
patchy reductions in visibility will dissipate after
sunrise...leaving VFR conditions through the rest of the taf
period. Aside from some light cumulus through the daytime
hours...skies should be clear through the majority of the
forecast. Winds winds will shift from east-northeast to SW through the
forecast period...generally remaining at or below 10 knots. With
winds not expected to go calm tonight...the potential for fog
should be limited.

Early Saturday morning...clouds will gradually increase in
coverage from south to north. These clouds are expected to be in
the VFR range (4000-5000 feet) but could be a little lower in
patches. Winds will increase in intensity on Saturday
afternoon...with gusts of up to 20 knots possible.

Outlook...thunderstorms are possible from late Saturday night
through Sunday afternoon.


Iln watches/warnings/advisories...


near term...Hickman
short term...Hickman
long term...Hickman

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