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Area forecast discussion 
National Weather Service Jackson Kentucky
948 am EDT Wednesday may 27 2015

Update...
issued at 948 am EDT Wednesday may 27 2015

Low clouds continued to blanket most places at middle morning...but
there are quite a few holes. Based on forecast soundings and the
fact that the middle day sun angle is near the peak for the
year...think that we will still be able to erode the solid sky
cover into scattered clouds. Have maintained slight chance
probability of precipitation this afternoon...with dry air aloft and a lack of a
trigger/focus mechanism preventing any substantial coverage.

&&

Short term...(today through thursday)
issued at 301 am EDT Wednesday may 27 2015

A bit of a challenging forecast in the short term. The nam12 and
other short range models are having a difficult time coming into
agreement regarding precipitation occurrence today and tonight.
The nam12 and GFS models are producing very little quantitative precipitation forecast through 0z
Friday...while the European model (ecmwf) model is quite a bit wetter than either of
the other two models. The issue appears to be the lack of a good
trigger for convection...especially today. The MOS guidance is
also producing only very low precipitation probabilities across
the board for locations across eastern Kentucky. That all being
said...decided to keep the morning hours today free of
precipitation...with isolated showers and storms forecast for this
afternoon and early evening during peak heating. Also went ahead
and kept a small chance of rain in the forecast for tonight as the
models do try to bring a weak upper level disturbance across the
Ohio Valley. Increased precipitation chances for Thursday to the
chance range...as the models are trying to move some sort of weak
boundary southward across the area. With moist air still in place
across the area...we could see scattered showers and storms fire
up again on Thursday...particularly during the afternoon hours
during peak diurnal heating.

Temperatures today through tomorrow are still on track to be
warmer than normal given the air mass we have in place and the
expected southerly winds. Highs today and tomorrow will most
likely top out in the low to middle 80s across the area. Tonights
lows are expected to once again bottom out in the balmy low to middle
60s.

Long term...(thursday night through tuesday)
issued at 345 am EDT Wednesday may 27 2015

The models remain in good agreement with ridging gradually
breaking down across the western Atlantic and along the Gulf Coast
as deeper troughing swings across the periphery of the northern
U.S. This will allow for some residual troughiness to slowly work
through the Mississippi Valley through early next week...keeping
unsettled conditions in place across our region. The blended
guidance did come in a bit leaner on the probability of precipitation through the
weekend...as the upper and lower level features look a bit more
dampened compared to yesterday. Have stuck fairly close to the
given probability of precipitation...however will continue to undercut a bit more during
the nighttime periods...since the models tend to overdo
convection. Temperatures will average a bit above normal through
the weekend...and then cool a bit closer to normal for this time
of year into early next week.

&&

Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 707 am EDT Wednesday may 27 2015

The weather issue of note for the taf sites this morning is
stratus clouds. These clouds have created MVFR ceilings at
jkl...sme...and sym during the overnight and early morning hours.
Have updated the taf grids through 15z to reflect the low level
cloud cover. Anticipate that these clouds will erode away once the
sun is up...giving way to VFR conditions across the board. There
is a small chance of isolated showers and thunderstorms later
today...mainly during the afternoon and early evening hours. Due
to the isolated nature of the storms...no mention was made of them
in the tafs.



&&

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

$$

Update...hal
short term...Arkansas
long term...geogerian
aviation...Arkansas

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