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Area forecast discussion 
National Weather Service Jackson Kentucky
217 am EDT Monday Jul 28 2014

issued at 944 PM EDT sun Jul 27 2014

Updated the forecast to better reflect current conditions and model
trends. The area near the Tennessee border remains quite active with
strong to severe thunderstorms, this area is moving to the south and
should be into Tennessee by midnight. The area of storms in Johnson
and Martin remain sub severe and they with be moving into West
Virginia by 11 PM. The actual cold front in entering Fleming County
from the northwest. There will be clearing behind the front. The
storms with the front should also be decreasing in intensity over the
next couple of hours.

Update issued at 858 PM EDT sun Jul 27 2014

Updated the forecast to extend the Tornado Watch through 2 am. The
activity will be far more scattered this evening than what we saw
earlier...however the environment is still unstable. Looking for the
activity to show a downward trend as the sun GOES down.

Update issued at 622 PM EDT sun Jul 27 2014

The most intense activity has exited south and southeast out of the
jkl forecast area. There is still unstable air upstream trying to
advect eastward into the area. Based on trends...confidence is low
for additional significant severe development this evening...but
would not rule out the need for another warning to be issued. After
coordination with lmk and Storm Prediction Center...have left the Tornado Watch in place
early this evening.


Short term...(this evening through Monday night)
issued at 440 PM EDT sun Jul 27 2014

Severe weather event was ongoing during the afternoon. Main threat
has been large hail...with reports up to softball size so far. Models
have not handled the convective development well at all today. Have
highlighted the current radar activity for high probability of precipitation...blending to
probability of precipitation for tonight which are highest in the southeast...where the
threat of precipitation persists the longest tonight before stabilization
takes place from northwest to southeast. Severe weather threat will persist into this
evening...with strong instability and ample shear. The shear will
become less directional and more speed as time GOES by. In
addition...very dry air will be present in the middle levels. These
factors would suggest hail continuing to be the most significant
threat. However...with storms being more surface based late in the
day now...winds and even tornadoes still need to be considered.

The surface cold front will pass southeast out of our area overnight.
Residual low level moisture will still be getting scoured away on
Monday. Forecast soundings would still allow for some showers to pop
up on Monday afternoon and into the evening. This would be more
probable in the NE part of the area where middle level temperatures will be
coolest. Middle level temperatures may prevent any precipitation in our far SW...and
will likely prevent thunder elsewhere. Any precipitation will die out Monday
night as heating is lost and the middle level cap strengthens.

Long term...(tuesday through sunday)
issued at 256 PM EDT sun Jul 27 2014

The models start out in very good agreement with an upper low over
Hudson Bay with an upper trough extending south across West Virginia
to Florida. There is an upper high center over West Texas with an
upper ridge extending into Alberta. At the surface...the back end of
the previous system will already be through the area. The upper low
will stay quasi stationary and with time the upper trough retrogrades
a little to the west. This type of pattern is conducive for mesoscale convective system
development to possibly then move across the area as short waves move
down the back side of the upper trough. With this upper high in
place...the seasonably cool weather continues for the Great Lakes and
the Ohio Valley...while it will be sweltering and dry out west.
The models are in good pretty much went with the model
blend and then made some correction due to elevation differences. On
the days thunderstorms are forecast...the storms will be mostly during the
afternoon and early evening.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 216 am EDT Monday Jul 28 2014

Thunderstorms and rain has finally moved out of eastern Kentucky and dry conditions should
prevail through the remainder of the night. The cold front is also
traversing eastern Kentucky at the moment...with much lower dew points
filtering in behind. This...along with some decent prevailing
winds...should eliminate the threat for fog at most taf sites. Kjkl
is currently the this site received heavy rains just
recently and lingering low level moisture has turned into ground fog
near the Airport. A little uncertain as to how long the fog will
stick around...but expect it to mix out at some point tonight. For
tomorrow...skies will be scattered to broken VFR with some higher wind gusts
possible during the afternoon at kloz...ksme...and possibly ksjs.
There is the potential that some of the taf sites could see some
light rain showers in the afternoon...but little to no impacts are
expected. And while some light br development is possible tomorrow should occur after the end of the taf period. As a
result...chose to leave both the mention of rain and fog out for
tomorrow/tomorrow night.


Jkl watches/warnings/advisories...


short term...hal
long term...jj

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