Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Jackson Kentucky
1030 am EDT Thursday Jul 10 2014
issued at 1030 am EDT Thursday Jul 10 2014
Forecast is on track this morning. Made the typical tweaks to the
grids to bring them in line with hourly trends. Otherwise...can not
rule out isolated showers or even a thunderstorm or two over our far
southeast during the day. European model (ecmwf) and GFS hint at the potential of an
isolated pop up north of i64 as short wave trough transits the Ohio
Valley today. But forecast soundings are not advertising as deep a
moisture profile as compared to southern locations across the County Warning Area.
Decided to stick with inherited dry conditions in the north which
also fits better with consensus of adjacent offices as well.
Update issued at 748 am EDT Thursday Jul 10 2014
Updated the forecast to better reflect current conditions and model
trends. Any remaining valley fog should burn off by 9 am.
Short term...(today through friday)
issued at 230 am EDT Thursday Jul 10 2014
The models are in good agreement in the short term with the general
pattern...however the GFS is showing a little more precipitation
potential today as an upper trough moves across the area. The NAM
is showing some shower activity along the southern border with
Virginia and Tennessee...however the GFS is showing a potential for
showers across most of eastern Kentucky today. Initially have sided
with the NAM. However may make a last minute change when the new
European model (ecmwf) comes in after 3 am. For temperatures...used a blend of the
NAM and GFS MOS that has been adjusted for bias and elevation
effects. Once this upper trough moves through latter this
afternoon...the rest of the period will be dry with seasonable
temperatures. The normal valley fog can also be expected.
Long term...(friday night through wednesday)
issued at 241 am EDT Thursday Jul 10 2014
Models are in pretty good agreement now through the upcoming weekend
and have really backed off on precipitation chances. Thus...looking
more and more like a pleasant weekend is on tap. Weather will turn
more unsettled early next week...as a couple shortwaves push across
the Ohio River valley...which will help drag a cold front across
Kentucky Tuesday into Tuesday night.
High pressure will continue to provide dry weather through Saturday
night. A shortwave will pass by just to the north of Kentucky on
Sunday...and could provide just enough support to pop a few showers
or storms across eastern Kentucky. It looks like any activity on
Sunday would be very sporadic with most areas staying dry since most
of the better forcing will stay north. A better looking shortwave
will dive across the Ohio Valley late Sunday night into Monday...
providing a much better chance for showers and storms. Have gone
with a period of likely probability of precipitation as this wave traverses the area. A
potent vorticity maximum will then swing across the Great Lakes on Tuesday...
propelling a cold front southward across eastern Kentucky. Again we
should see a period of showers and storms. Much cooler and drier
weather will return by midweek as the front settles to our south.
However...still some question as to how far south the front will
make it and if it stalls close enough to the area...we could see a
few showers spread across our southern zones into Wednesday.
However...confidence is low on precipitation chances beyond Tuesday
night. It does look like we should dry things out by late in the
week as the boundary drifts farther south and washes out.
Aviation...(for the 12z tafs through 12z Friday morning)
issued at 748 am EDT Thursday Jul 10 2014
Any valley fog should burn off by 9 am. After that...it should be VFR
until some more valley fog form again after midnight.