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Area forecast discussion 
National Weather Service Jackson Kentucky
347 PM EDT sun may 24 2015

Short term...(this evening through Monday night)
issued at 347 PM EDT sun may 24 2015

Upper level ridging has been shifting eastward across the Ohio River
valley throughout the day as broad troughing and an upper level
closed low continue to expand across the western half of the Continental U.S..
much of western Kentucky and the Mississippi River valley is finding
itself wedged in between the two patterns with increasing pressure
gradients...resulting in some breezy conditions across much of the
western and central portion of the state. Here in eastern
Kentucky...ridging is still trying to hold on for the next few hours...but
expect heights to be on a slow decline throughout the night and into
the day tomorrow as the upper level troughing begins to cross over
the Mississippi River valley. A river of moisture is currently
streaming from the Gulf of Mexico upwards through the Mississippi
River valley and then wrapping itself into the strong low currently
cover the northern plains...or eastward up and along the northward
extent of the upper level ridge. This is resulting in a large amount
of cloud cover across these above mentioned areas. While a few
clouds have found their way into eastern Kentucky...we are generally
mostly sunny with strong but dry southerly flow as of 1930z. As the
ridge continues to break down overnight...and the upper level trough
nears closer...expect these clouds to expand across Kentucky...generally
of the high variety...though some middle and lower clouds may begin
moving in as early as tomorrow morning.

Along with these clouds...there will continue to be an uptick in
moisture and temperatures for the day tomorrow. A shortwave moving
up and along the exiting ridge will provide a strong enough trigger
to allow scattered showers and thunderstorms to begin developing
tomorrow during the day...increasing in coverage and intensity as we
head into the afternoon hours with peak heating and instability. As
the ridge continues to break down over the east...expect this
convection to spread across the entire County Warning Area during the day. Loss of
daytime heating and fuel will allow for a diminishment in coverage
overnight Monday night...but continued lowering heights and more
shortwave influence will allow for showers and thunderstorms to
quickly begin ramping up again by Tuesday morning.

For temperatures...strong southerly flow across the region allowed
temperatures to make it into the low and middle 80s this afternoon. With
increasing moisture...continued strong southerly flow...and the
potential for an uptick in cloud cover overnight...expect overnight
temperatures to be much warmer than nights previous. Generally upper
50s to middle 60s are expected. We could still see some decent ridge to
valley temperature differences...but expect that given the above
mentioned factors...the best potential for this to occur will be in
the terrain across the far eastern portion of the County Warning Area...away from
the best cloud cover and wind influences. Temperatures could fall as
low as the low to middle 50s in some of these valleys overnight. By
tomorrow...two things will come into play. First...stronger
southerly flow across the region which would promote a continued
warm up across the region. However...this may be offset by
encroaching cloud cover and the possibility for rain. As
such...expect similar temperatures overall to that of today...generally in
the low to middle 80s. Temperatures will obviously likely fluctuate as
rain showers/thunderstorms pass over. tomorrow
night...the increasing clouds and moisture will work to alleviate
the large Ridge Valley differences...and will keep temperatures generally
mild across the the low to middle 60s for overnight lows.

Long term...(monday night through saturday)
issued at 300 am EDT sun may 24 2015

The extended looks to be active and wet as a series of weather
systems are prognosticated to move across the eastern third of the Continental U.S.
From Monday night Onward. The GFS...nam12...and European model (ecmwf) models all had
different solutions to some degree...with differences amongst the
three regarding timing of weather system passage and the diurnal
pattern of precipitation. The large scale pattern looks to feature a
series of large scale upper level troughs...with sluggish frontal
boundaries moving eastward at the surface. These weather systems
will be the trigger for precipitation during the upcoming week. In
general terms...eastern Kentucky can expect periods of showers and
thunderstorms throughout the upcoming work week...with the peak
activity likely occurring during the afternoon and early evening
hours. Patchy valley fog will also be possible each day and was
included in the grids yet again. Temperatures during the period are
still expected to be above normal with day time highs topping out in
the lower 80s and overnight lows falling into the low to middle 60s.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 137 PM EDT sun may 24 2015

VFR conditions will continue at the taf sites over the next 24 hours.
Some patchy River Valley fog is expected again tonight...but
should not impact taf sites. Otherwise...expect some thin high
clouds and occasional patches of middle level clouds to drift across
the area from time to time today and tonight. South winds have
begun ramping up across central Kentucky this
included mention of higher winds and potential gusts for
ksme/kloz/and ksme before tapering them off after 00z Monday. Some
middle/lower clouds will begin to move into the region by late
tonight and into the day tomorrow...mainly at the above mentioned
taf sites closer to the central and northern portion of the state.
These ceilings should generally remain in the low end VFR category. Expect
any rain concerns to hold off until after 18z...though did go
ahead and include vcsh for the far most western taf site /ksme/ in
case things begin moving in an hour or two faster than predicted.


Jkl watches/warnings/advisories...


Short term...jmw
long term...Arkansas

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