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Area forecast discussion 
National Weather Service Jackson Kentucky
533 am EDT Friday Mar 27 2015

Short term...(today through saturday)
issued at 358 am EDT Friday Mar 27 2015

The main batch of precipitation has worked southeast of the area
during the overnight hours...with only some remaining very light
rain/drizzle left across the far southeast. Temperatures have
settled into the middle and upper 30s across the Bluegrass where
clouds have thinned. Most other locations are in the upper 30s
and lower 40s...with the exception of the highest terrain
bordering Virginia...where lower 30s and possibly high 20s are in
place.

The models are in good agreement through the short term...with a
deepening trough axis currently taking shape across the central
Continental U.S. To move east across the Mississippi Valley through tonight.
The trough will usher in much colder air aloft...and this will
help to initiate some shower activity across eastern Kentucky
this afternoon and into this evening. In fact...the forecast
soundings suggest that even some thunder may be possible. Will
leave out a mention for now...but would not be surprised to a few
thunderstorms and possibly even some graupel within the most
intense updrafts.

Convection will diminish into this evening as the trough axis
shifts east...with some snow showers to finish as low level
temperatures cool off enough. High pressure will build in from the
Great Lakes later this evening...with decreasing clouds and lows
getting down into the low to middle 20s for most locations.

Long term...(saturday night through thursday)
issued at 533 am EDT Friday Mar 27 2015

Model solutions are similar enough with middle and upper level features
that confidence is a little higher than normal for the extended. We
are generally looking at a progressive...quasi-zonal pattern with a
few...relatively low amplitude shortwave disturbances to deal with
through the period. Models appear to have a decent handle on the
first shortwave which moves through the region Sunday night into
Monday. This first system should provide a good chance of rain
showers late Sunday night into Monday morning.

Models agree on timing another disturbance through the region late
Tuesday...Tuesday night but the European model (ecmwf) advertises a slightly stronger
system...especially at the surface. As a result...the European model (ecmwf) brings a
moisture starved surface cold frontal boundary through eastern Kentucky
and just to our south by Tuesday night. With the weaker middle/upper
level support of the GFS...this frontal boundary stalls north of the
Ohio River. However...it is Worth mentioning that the GFS is also
stronger with return flow to the south of this boundary.
Consequently the GFS solution hints at the potential of some
precipitation through the middle term while the European model (ecmwf) remains dry. For
now leaned towards consensus...which is dry.

From there models begin to diverge more significantly...with the GFS
swinging a third more significant shortwave across the region at the
end of the extended. The European model (ecmwf) suggests a weaker shortwave that
shears out across the Great Lakes in response to energy digging a
more amplified trough across the western Continental U.S.. interestingly...both
models still bring a well defined cold front...with similar surface
features and precipitation through the commonwealth at the end of
forecast window.

For sensible weather...our most significant subject matter
continues to be the cold weather at the start of the extended. We
are expecting temperatures to drop into the teens Sunday morning.
Very dry air above the boundary layer and dew points at the surface in
the single digit to teen range will make for very good radiative
cooling. Surface high pressure centered over the south central
Appalachians...slightly east of our area will keep our winds light
at best. So we can expect a hard freeze across the area again
Saturday night into Sunday morning. Did bring temperatures up just
slightly in our western most zones...into the lower 20s...as there
may be a slight southerly return flow setting up across those
areas. Temperatures return to normal levels fairly quickly through
the remainder of the extended. However...models suggest the
possibility of another shot of very cold air next weekend as h850
temperatures drop back down around -10c.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 225 am EDT Friday Mar 27 2015

IFR/MVFR ceilings will gradually break up from northwest to
southeast through dawn as precipitation winds down across the
area. VFR conditions will likely hang on through Friday despite
the approach on an upper level disturbance which will bring the
threat of a few more showers to the area for the afternoon and
early evening hours. Winds will remain at 5 to 10 kts through the
period...generally out of the north and northwest.



&&

Jkl watches/warnings/advisories...none.

&&

$$

Short term...geogerian
long term...ray
aviation...geogerian

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