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Area forecast discussion 
National Weather Service Jackson Kentucky
1045 PM EDT Monday Sep 1 2014

Update...
issued at 1045 PM EDT Monday Sep 1 2014

Isolated showers continue to affect northern Kentucky...including the
northern part of the Jackson forecast area. The showers have shown a
decreasing trend...and the total lightning data indicates there is no
longer any lightning in Kentucky. Convection continues to develop across MO
and central Illinois. Based on current trends and the latest hrrr data this
could impact our area beginning sometime near of after 12z. Hourly
ndfd data has been updated for latest observational trends.

Update issued at 751 PM EDT Monday Sep 1 2014

Isolated thunderstorms continue to affect the northern third of
Kentucky...including the northern part of the Jackson forecast area. With
loss of daytime heating expect the isolated convection to continue to
wane. However a short wave moving into MO is resulting in an
increase in showers and thunderstorms ahead of the surface cold front
there...and the remnants of this convection may affect the northern
parts of the forecast area late tonight or early Tuesday morning. This
idea is supported by the latest hrrr and the 18z NAM and GFS. Have
updated ndfd for latest observational trends and will be making
additional adjustments to hourly weather grids shortly.

&&

Short term...(this evening through Tuesday night)
issued at 315 PM EDT Monday Sep 1 2014

A line of scattered showers and thunderstorms continues to move
across eastern Kentucky. This line is out ahead of the cold front in
the warm air. There is a bit of curvature to the line of heaviest
storms;...so will be watching for some potentially strong wind gusts
as the line GOES through. The Mercer and Lincoln County mesonet
sites saw wind gusts of 30 miles per hour as the line went through and Bath
County saw a gust to 41 miles per hour. Current thinking is the maximum gusts stay
around 40 miles per hour with the strongest storms and most gusts will be in
the 25 to 35 miles per hour range as the storms continue to move across eastern
Kentucky. These storms will drop between 0.25 to 0.75 inches of rain
as it moves across the area. Have a little concern for parts of
eastern Kentucky that got hammered last night from the heavy
rain...however these storms have been quite progressive and have not
yet seen any training of the echoes. This line should continue to
move across the area and then the leading edge of the prefrontal
precipitation will be moving into the area later tonight. The front
will be moving across the area tomorrow and bring widespread showers
and thunderstorms to the area. There will be a slight risk of severe
thunderstorms tomorrow. Storm Prediction Center currently has most of eastern Kentucky
in the slight risk area. The main threat will be winds with a very
weak threat for marginally severe hail. Most likely...any hail will
stay in the 0.5 to 0.75 inch range. The precipitation will drop off
fairly quickly behind the front. The models are in very good
agreement with the timing. Went with the model blend for the
temperatures with just some adjustments due to elevation.

Long term...(wednesday through monday)
issued at 315 PM EDT Monday Sep 1 2014

The models begin the extended period in pretty good agreement once
again...with a ridge of high pressure...both aloft and at the
surface...centered over the eastern Gulf of Mexico...along with a
well defined trough of low pressure aloft taking shape over the
northern plains. The models have the ridge breaking down
consistently to begin the period...with showers and storms popping
up beneath it across the Tennessee Valley down to the Gulf. As the
trough evolves and strengthens...it will eject out of the plains
Wednesday night and Thursday...and push across the Great Lakes and
Ohio Valley regions. The cold front trailing from this upper low
will end being our weather maker for the upcoming weekend. The front
is expected to interact with moisture coming off the Gulf of Mexico
on southwesterly winds. The front will have a difficult time moving
eastward...however...as the ridge digs in a bit just off the
southeast coast and flow aloft becomes more zonal. There will be a
good chance of rain Friday morning through Sunday morning...as lift
and moisture along the sluggish front set off repeated rounds of
showers and storms. The rain should finally move out of the area
Sunday evening...as the front finally moves out of the area.

Temperatures to begin the period look to be above normal...with
highs topping out around in the middle to upper 80s Wednesday through
Friday. Once the front stalls across the area and precipitation
becomes more widespread...temperatures will likely maximum out below
normal values Saturday through Monday. Highs on Friday will be
closer to normal as the front will still be to our west. On Saturday
and Sunday...the positioning of the front will allow for some cooler
and drier air to filter into the area. Highs on Saturday should be
close to normal...as the bulk of cool air should still be trapped
north of the Ohio River. On Sunday...however...once winds have
shifted to the north...temperatures will be quite cool...with
readings peaking in the middle to upper 70s.

&&

Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 751 PM EDT Monday Sep 1 2014

Isolated thunderstorms over northern Kentucky...north of the taf sites...
will diminish this evening. VFR conditions will prevail until after
06z when areas of fog will begin to form. MVFR conditions in fog are
expected late tonight and early Tuesday morning...but any fog will
burn off quickly Tuesday morning. VFR conditions will prevail for
most of the day on Tuesday...but an approaching cold front will bring
a threat of thunderstorms during the afternoon and evening. Southwest
winds will become gusty ahead of the cold front Tuesday
afternoon...with some gusts in excess of 15 knots.



&&

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

$$

Update...sbh
short term...jj
long term...Arkansas
aviation...sbh

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