Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
348 PM EDT Monday Sep 22 2014
a large area of high pressure over the northern and Central Plains
will settle over the Ohio Valley tonight and Tuesday. High
pressure is then forecast to extend across the region through the
end of the week. Temperatures will start out cool early this
week...followed by a warming trend.
Near term /until 6 am Tuesday morning/...
high pressure building in tonight. Clouds pushing off to the east.
Setting up for coolest night so far in September and since middle
of may. Widespread 40 to 45 range with upper 30s likely in the
colder locations. Will probably have reports of spotty frost but
not expecting enough impact for headlines. Fog may develop in
river valleys but again not expecting enough to warrant mention in
Short term /6 am Tuesday morning through Wednesday night/...
surface high pressure will settle over the Ohio Valley. Dry air
mass with mainly clear skies. Atmosphere warming over period and
expect a good recovery from cool morning lows. Will likely see big
diurnal range. Have gone near guidance but a bit on the cooler
side for lows with light winds and clear skies.
Long term /Thursday through Monday/...
middle/upper level ridging will remain in control through the long term
period. The models are hinting at some moisture possibly trying to
work up from the south early next week with a short wave digging underneath
the established upper ridge. Have kept a dry forecast with a slight
increase into low chance probability of precipitation on Monday.
As the airmass slowly modifies...expect a gradual warming trend
through the end of the week with high temperatures running a few
degrees above normal. Erred on the warm side of daytime highs and
the cool side of nighttime lows given the dry airmass. This still
puts temperatures about 7-8 degree above normal on highs and 4-6 degree above on
lows. Guidance really only had a 2-4 degree range on both highs and
lows through the entire extended period...indicating fairly high
confidence in the overall pattern and the forecast temperatures.
Aviation /20z Monday through Saturday/...
high pressure and a very dry airmass are moving in at the surface
and aloft. This will provide mainly VFR. Once the few cumulus that
remain dissipate later this afternoon...skies will be clear
tonight...with only a few cumulus expected to form on Tuesday.
Under light winds...visibility may be reduced by br late tonight
at luk and iln. Light easterly winds are forecast for Tuesday.
Outlook...no significant weather is expected.