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fxus63 kjkl 182030 
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Area forecast discussion
National Weather Service Jackson Kentucky
430 PM EDT sun Aug 18 2019

Short term...(this evening through Monday night)
issued at 430 PM EDT sun Aug 18 2019

19z sfc analysis shows high pressure over eastern Kentucky and
its subsidence has helped to keep the clouds to a minimum
supporting a hot afternoon as readings made it into the 90 to 95
degree range for many places. Dewpoints have actually come down
during the afternoon due to a mix down of somewhat drier air and
are now in the low to mid 60s, in general. This has yielded heat
indices mainly in the 95 to 100 degree range - despite the higher
temperatures - below the stifling heat of a few weeks back. Winds
have been mainly light from the southwest this afternoon with a
few gusts to 10 kts. Some pinprick thunderstorms have also popped
up in the far south and these could spawn a few additional ones
into the early evening hours. For this reason have included a pre-
first period in the zones to cover them for the next several
hours.

The models are in pretty good agreement aloft through the short
term portion of the forecast period. They all depict one last
shortwave to brush by to the north of Kentucky tonight. This wave
passes before higher heights come north as the southern ridge
builds further into the start of the new work week. The mid level
flow slows during this time, as well, though it does set up a
divergent pattern that will need to be contended with on Tuesday
when the next shortwave moves through the Ohio Valley. Given the
general model agreement aloft will again favor the nbm and its
blended solution with some consideration of the cams in the near
term.

Sensible weather will feature a warm evening with dying isolated
convection and clearing cu toward sunset. This will set up a mild
night again beneath some high clouds from storms to the northwest
- likely limiting the fog formation to the river valleys. In
addition, the high clouds will have a moderating effect on our
ridge to valley temp differences through the night. Look for
another hot day on Monday, but the dewpoints should be a tad more
moist and more clouds keeping readings a tad lower. Again some
higher terrain storms will be possible in the southeast in the
afternoon but kept pops just below 15% there. Late in the day some
storms from the northwest could make it into the area before also
dying off - for this have allowed slight chance pops but also
kept them into the night northwest as boundaries stick around.
Again a smaller ridge to valley difference can be expected Monday
night with more clouds and higher dewpoints in place. More clouds
should also help keep fog to a minimum - again limited to the
river valleys.

The nbm was used as the starting point for all the grids with only
minor adjustments to temperatures at some points along with minor
ridge and valley differences added tonight and Monday night. For
pops, again focused on the higher southeast terrain at peak
heating into the evening - above nbm - and also the northern
activity Monday afternoon also exceeding the model's numbers.

Long term...(tuesday through sunday)
issued at 300 PM EDT sun Aug 18 2019

The weather pattern in the extended will feature a large ridge of
high pressure situated over the southeast conus, mid Atlantic region
and the Tennessee Valley to start things off. We will also see a
large trough of low pressure aloft moving across the Great Lakes and
Ohio Valley regions from mid week Onward. This trough will
eventually make its way into New England by next weekend. The trough
should be strong enough to break down the surface ridge, thereby
pushing it off to our east as the week wears on. This low pressure
system, and its attendant slow moving frontal boundary, will bring
rain chances to eastern Kentucky each day in the extended. The best
chances for rain should be from Wednesday through late Thursday
evening, as the front gets temporarily hung up over the area. We
should see showers and storms tapering off steadily late Thursday
night and Friday, as the front finally drifts off to our south and
southeast. The front should remain close enough to the area to keep
rain chances in the picture going into next weekend as well.

High temperatures will likely start off well above normal to begin
the period, with highs in the upper 80s and lower 90s expected for
Tuesday and Wednesday. After that, we should see a return to normal
or maybe even slightly below normal highs to end the week and going
into the weekend. Highs on those days are forecast to reach into the
low to mid 80s for most locations. Nightly lows will start off only
falling into the upper 60s to lower 70s, with low to mid 60s min
readings expected from Wednesday night into the weekend.

&&

Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 210 PM EDT sun Aug 18 2019

VFR conditions will prevail into Monday, aside from some MVFR or
worse fog seen in the deeper river valleys between 06 and 12z.
Some diurnally driven cumulus at 4-6k feet agl will also be around
this afternoon and again by midday Monday. South to southwest
surface winds will average less than 5 kts through the period with
a period of near 5 kts expected in the afternoons.

&&

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

$$

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