Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
724 PM EDT Thursday Jul 2 2015
a stalled frontal boundary is currently located near the Ohio River.
Low pressure is forecast to move east along this boundary tonight
into Friday...keeping a chance for showers and thunderstorms. High
pressure will keep chances more limited over the weekend.
Temperatures will remain slightly below normal through early next
Near term /until 6 am Friday morning/...
models are in agreement in keeping a front stalled near the Ohio
River overnight. There are slight disagreements however in the
strength and path of the surface low. This causes differences in the
placement of precipitation overnight. The best chance of precipitation will be in
our northern Kentucky counties with decreasing chances as you head north.
Went high chance to likely probability of precipitation in northern Kentucky this evening with
a little lower pop later in the night. Went dry north of the U.S.
35 corridor. With very little flow over the region...the storms
that develop are slow movers and capable of producing brief heavy
rain. Will continue the Flash Flood Watch overnight to cover this
As for low temperatures tonight...the typical north-south gradient
will be in place. Upper 50s in west central Ohio...up to middle 60s
in northern Kentucky.
Short term /6 am Friday morning through Saturday night/...
surface low continues its slow journey eastward on Friday. This will
keep the same pattern that we have had for the past couple of
days. The highest probability of precipitation in Kentucky with decreasing probability of precipitation as you
head north. Went with likely probability of precipitation in northern Kentucky on
Friday...tapering up to slight chance pop in west central Ohio. With
the surface low in the vicinity providing lift...will keep the flash Flood Advisory
going until 00z Saturday.
High pressure building into the middle MS valley tomorrow night will
help bring some drying to the region as it pushes the boundary a
little to the south. After lingering chances in the evening...the
later half of Friday night should be dry. Cant totally rule out
something developing across the southern third of the forecast area on
Saturday...as they will remain on the fridge of the development
near the boundary.
Temperatures will continue to be slightly below normal. Temperatures
on Friday were kept in the middle to upper 70s...with clouds and
precipitation chances again. With a little more sun...values
should come back into the upper 70s to lower 80s on Saturday.
Long term /Sunday through Thursday/...
a surface low south of the area will move east at the beginning of
the period and some lingering showers will be possible along and
south of the Ohio River through Sunday afternoon as an upper low
lingers over Kentucky. Ridging will build behind it overnight and
Monday with southerly surface flow setting up ahead of the next
The upper low is slow to exit the East Coast and this has apparently
slowed the expected progression of the next cold front to early
Wednesday. Increasing chances for showers and thunderstorms will be
found Tuesday evening and especially overnight.
The synoptic systems begin to diverge depending on the model used
beyond this time. Regardless of how they develop...it looks similar
to the current pattern with frequent periods of passing showers and
storms. Have higher chance probability of precipitation through much of the extended. High
temperatures are a bit muted and generally below climatology given the
expected passing rain and cloud cover...with lows at or just above
climatology for the same reasoning.
Aviation /00z Friday through Tuesday/...
a stalled boundary remains along the Ohio River this evening
allowing showers to continue in its vicinity. Main taf sites this
will affect are kcvg and kluk. Expect coverage to continue to
decrease this evening as we loose day light.
Overnight the sref is showing some reduced visibilities and lower
ceilings. This makes sense as winds will remain light near the frontal
boundary and the ground will still be wet. This again will mainly
be at kcvg/ kluk. Further towards the north where less rain fell
think the chance of reduced ceilings/visibilities will be much less. GFS and
NAM forecast soundings also show this.
During the day Friday a surface low will move across northern
Kentucky/ southern Ohio and will bring another chance of showers
and isolated thunderstorms to the area. Forecast soundings are
showing limited instability tomorrow so for now have left as vcsh
but thunder might have to be added later. Also am thinking
coverage might be a little bit more widespread than today.
Forecast models have the track of the upper level low now through
central Ohio and some high res models have also pushed the chance
of rain slightly further north. For this reason have added a vcsh
to all taf sites.
Outlook...thunderstorms possible on Tuesday.
Kentucky...Flash Flood Watch through Friday evening for kyz089-090-
In...Flash Flood Watch through Friday evening for inz080.