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Area forecast discussion
National Weather Service Jackson Kentucky
404 am EDT Thu may 25 2017

Short term...(today through friday)
issued at 353 am EDT Thursday may 25 2017

Morning surface analysis shows an area of quasi stationary low
pressure resides across SW Ohio as it becomes vertically stacked. A
spoke of positive vorticity advection and area of surface convergence will swing across the
region today. This will bring periods of showers to much of the
region through the day. There will be some convective element, but
really start to transition to stratiform elements. Therefore, not
overall impressed with the efficiency these showers will have
through the day. However, ffgs remain low in parts of the far east
I.E. Martin/Pike counties, but still just below one inch range
for even the 1 hour. That said think this will be a longer
duration rainfall than 1 hour and not confident we will see
widespread issues in these areas given the longer duration
rainfall. Given leaned away from issuing a ffa, but will mention
the isolated issue in the severe weather potential statement.

This pesky upper level low will push east through the evening into
tonight. This will pull the surface low pressure east and
subsequently the showers will taper off from west to east through
the night. Heights will be on the rise and some clearing could
lead to some minor temperatures splits by Friday morning mainly in
the western parts of the County Warning Area. The previously mentioned height
rises will also usher in warmer 850mb temperatures by Friday
afternoon and lead to temperatures 15 to 20 degrees warmer than
today. Clouds will likely be on the decrease, but some high clouds
will remain particularly in the afternoon on Friday.

Long term...(friday night through wednesday)
issued at 404 am EDT Thursday may 25 2017

Cyclonic flow will remain locked in place from the Southern Shores
of Hudson Bay into the Tennessee Valley from this weekend well into
next week, as upper ridging traverses the Gulf Coast into the
western Atlantic and split flow sets up across the western U.S. Net
impact for eastern Kentucky will be an unsettled pattern
characterized by periods of showers and thunderstorms along with
seasonable temperatures, beginning the weekend above normal and
falling to near or slightly below normal by mid next week.

Quasi-zonal flow Friday night will back southwesterly Saturday as an
upper low migrates into Manitoba, sending several upper impulses
downstream as far south as the volunteer state. Isolated showers and
storms will develop Friday evening and night, with scattered storms
occurring throughout the day Saturday. These should remain rather
low-topped as height falls and deep layer shear will be weak along
with their primary forcing being driven aloft as an earlier day warm
front should be well north of eastern Kentucky by peak heating. More
widespread convection will materialize into Sunday as the upper low
moves east toward the western Great Lakes and an attendant surface
low slides across the upper Ohio Valley toward the lower Great
Lakes. An approaching cold front will serve as focus for
thunderstorm development through the day into Monday morning. Will
have to monitor progression of the boundary for flooding potential
Sunday, before a damaging wind threat likely materializes later in
the afternoon into the night. This widespread precipitation will
knock a few degrees off of temperatures when compared with readings
in the low 80s Saturday, as sunday's highs top out in the upper 70s.

Rain chances will diminish from west to east Monday behind the
front, with another round of storms possible Tuesday ahead of a
secondary upper wave and front. Dry conditions should return for a
portion of midweek before another round of showers looks possible
thereafter on the western edge of the slowly eastward meandering
upper low. This feature should keep temperatures in check with highs
near the mid 70s and lows in the mid 50s.

&&

Aviation...(for the 06z tafs through 06z Thursday night)
issued at 136 am EDT Thursday may 25 2017

The rain showers have tapered off across the region this hour and
this will be the case till we get closer toward dawn for most.
The latest obs and trends suggest a general downward trend in the
cigs toward dawn as well and right now will go near IFR. Then
went IFR for most by the 14z to 15z timeframe. This as northwest flow and
upper low provide ample stratus for the taf period. Also another
area of showers will progress across the region from northwest to southeast
through the day beginning in the Bluegrass by around 13z. Winds
will also be on the increase through the day given decent low level jet and
therefore do have 15 to 20 knot gusts mainly in the Bluegrass and
Lake Cumberland regions.

&&

Jkl watches/warnings/advisories...
none.
&&

$$

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