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Area forecast discussion...updated 
National Weather Service Jackson Kentucky
755 am EDT Friday Oct 24 2014

issued at 745 am EDT Friday Oct 24 2014

Did a quick update to reflect the current observation and trends. Also
touched up the sky cover over the next few hours. These have been
sent to the ndfd and web servers.


Short term...(today through saturday)
issued at 255 am EDT Friday Oct 24 2014

06z surface analysis shows weak high pressure in place over eastern
Kentucky. Even so...a fair amount of high clouds are passing overhead
this night as a consequence of a middle level trough approaching the
Ohio Valley with a healthy pool of energy. These clouds ruined...for
many in eastern Kentucky...a shot at seeing the partial solar
eclipse early Thursday evening. Now they are helping to keep
temperatures from completely bottoming out...likely leading to only
patchy fog for the valleys...though locally dense pockets will be
possible in the far east towards dawn. In addition...a few specks of
light frost cannot be ruled out in some of the colder valleys
locations...away from creeks...lakes...and other bodies of water near
dawn. Currently a moderate ridge to valley temperature split exits
- running from the upper 30s in the deeper eastern valleys to the
middle 40s on the ridges while winds remain light and variable.

The models are in good agreement aloft through the short term portion
of the forecast. The all take a small...but sharp...trough through
eastern Kentucky and the southern Appalachians later today. This will
be followed by the strong Big Bend Ridge spreading east while a
trough and its energy pass quickly by to the north into the start of
the weekend. Heights over eastern Kentucky will rise throughout the
process protecting the area from any northern intrusions of colder
air and any precipitation threat. Given the overall model sameness have
followed the latest higher resolution nam12 model most closely for
the short term...mainly temperature/cloud...forecast.

Sensible weather will feature partly to mostly cloudy skies and
warming temperatures today. This will be followed by additional times of
clouds and clearing...dictated by the fast flow aloft...tonight
through Saturday. With no real threat of precipitation on the docket we can
focus the forecast on the pleasantly mild temperatures...for middle
October...on tap through the weekend. Also expect readings to stay
out of the frost zone tonight with little concern for any more than
some localized fog patches in the valleys toward dawn Saturday. All
in all...a pleasant end to the week...with times of limited sunshine
the only potential drawback.

For temperatures...dewpoints...and winds followed the latest
consshort...and its British Columbia version...through the first 18 to 24 hours of
the forecast and the superblend thereafter. Did make some changes to
better reflect the Ridge Valley differences also expected to develop
tonight. Probability of precipitation thorough the period were kept line with the
minuscule values from the MOS guidance.

Long term...(saturday night through thursday)
issued at 245 am EDT Friday Oct 24 2014

Very mild/perhaps near record warmth will be the main story through
the extended for the early half of next week. The secondary focus
will be around a cold front and precipitation chances as it drops
through the area Tuesday night and Wednesday. Models are in fairly
good agreement through Tuesday night...before differences become
tougher to resolve. Thus...forecast confidence is decent up to the
frontal passage with less confidence Post frontal.

To start the period...middle level heights will continue to build
Saturday night into Monday as strong ridging spreads across the Ohio
River valley. Some pesky clouds could linger Saturday night in the
wake of the shortwave trough on Saturday. This may keep temperatures
a bit milder. Clouds should quickly erode on Sunday as subsidence
takes over...allowing a mild day with highs climbing back above
normal with readings into the lower 70s. With the ridge centered
over the area on Monday...this will likely be the warmest day with
highs easily into the upper 70s...and likely seeing some lower 80s
in places. With records in the low to middle 80s...we could threaten
the records. Same could be said about Tuesday as a cold front moves
into the Central Plains...the gradient should tighten up ahead of
the front continuing the warmth. With records slightly lower on
Tuesday...they could be more in jeopardy.

Models continue to agree on a the cold front passing through the
region Tuesday night. Given the model consistency and
agreement...have opted to go with a period of likely probability of precipitation.
Instability looks way to weak to support any thunder...especially
given the time of year. Both the European model (ecmwf) and GFS slow down the front
and stall it just to our southeast by middle week. GFS keeps it a bit
farther northwest...which may keep the threat of rain across
southeast Kentucky through at least Thursday. However...European model (ecmwf) keeps
things dry from Wednesday afternoon Onward. Opting to keep some low
probability of precipitation in the forecast as it may not be impossible to see a wave push
north...along the least temporarily bringing some rain
showers back into southeast Kentucky. By late in the week...we
should finally see an end to the rain chances.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 755 am EDT Friday Oct 24 2014

The MVFR fog at sjs and elsewhere will burn off between 12 and
13z...with VFR conditions prevailing thereafter. Expect fog to be
even less of an issue tonight after another day of drying. Winds
will remain light...generally out of the northwest during the daytime


Jkl watches/warnings/advisories...


short term...greif
long term...kas

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