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Area forecast discussion 
National Weather Service Jackson Kentucky
346 PM EDT Sat Jul 30 2016

Short term...(this evening through Sunday night)
issued at 308 PM EDT Sat Jul 30 2016

WSR-88D radar continues to show a few showers continuing to
develop across portions of the County Warning Area this afternoon. These could
expand a bit more in the northern portion of the County Warning Area as storms
move east out of northern central Kentucky. This has been brought on by
a weak upper level wave and a surface boundary near the Ohio
River. This is being handled fairly well by the cam data and sseo
and therefore have blended close to these short term models for
pops. Coverage wise these should be mostly diurnally driven but
given the cyclonic flow will keep at least slight pops overnight.

Sunday best pop coverage will reside in the southern portions of
the County Warning Area. This given less of a focus lifting wise within the upper
level pattern and the column lessen moisture wise given precipitable waters
finally drop into the 1.5 range. Therefore overall went toward a
more diurnal and topographical type scenario. Given the lessening
moisture going into Sunday night do actually expect that most
areas should see a end to the stormy activity for a change.
Temperature wise would expect most locations will remain near
normal through the period.

Long term...(monday through saturday)
issued at 345 PM EDT Sat Jul 30 2016

Somewhat deamplified troughing will be in place across the Ohio
River valley to start off the day Monday. A weak shortwave will
pass through this trough during the day Monday as the troughing
begins amplifying due to building high pressure over the
southwest conus. The upper level pattern will remain nearly
stationary through the day Tuesday, as the upper level high slowly
pushes into Kentucky Wednesday through the remainder of the week. A
strong upper level low passing across Canada late in the week and
through the weekend may cause heights to lower once more for the

With the presence of the trough in place across the region, a cold
front will also find itself draped across the state Monday. This
frontal boundary will push slightly southward late in the day
Monday, while still encompassing the western portion of the
state. This boundary will become nearly stationary through
midweek, and then will finally start to break down Thursday as
the upper level ridge moves into the region. The above mentioned
upper level low that will be traversing Canada into the weekend
will also produce a surface low pressure system. This will contain
a long surface frontal boundary, expected to swoop southward and
along the Ohio River by Friday night, then remaining nearly
stationary into Saturday.

With the frontal boundary in place through much of the workweek,
and temperatures expected to warm into the mid and upper 80s each
day, expect the available instability and lift to spawn showers
and thunderstorms each day, peaking during the afternoon/early
evening with warmest temps. Coverage is still somewhat sporadic
across the models, and without any strong forcing, did not see
need to go above slight chance to chance pops each day. The
exception will be the very end of the period, specifically
Saturday, when the stronger cold front is expected to enter into
the region and may bring about more numerous shower and
thunderstorm coverage. Also...after this Monday, winds will
become fairly light in the mid and upper levels, so storms may be
slow moving and pulsy. In good news, however, the precipitable water values
will be within tolerable values (well under 2 inches), so not
expecting any further flooding concerns (unless of course training
of storms over a specific location for a period of time occurs).


Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 142 PM EDT Sat Jul 30 2016

Starting off with a mix VFR/MVFR this taf issuance. WSR-88D radar
showing a few showers our beginning to develop generally along
and north of the I-64 corridor. Additional convection is setup
across north central Kentucky and will also spread east through the
afternoon. For now only went with thunderstorms in the vicinity given the more unknown on
who will actually receive a storm within the taf site area. Would
expect based on short term models that the best chances would be
generally along and north of the mountain Parkway. Then the next
issue will be the potential for fog/stratus overnight. This will
depend on cloud cover and early convection. Right now will keep
sites in the MVFR to IFR range for vis restrictions around 5z to
8z and only going scattered low deck at this point. Again winds will
remain light but gusty conditions with storms can not be ruled out.


Jkl watches/warnings/advisories...


long term...jmw

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