Area Forecast Discussion
Issued by NWS Jackson, KY

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FXUS63 KJKL 270136

Area Forecast Discussion
National Weather Service Jackson KY
936 PM EDT THU MAY 26 2016

Issued at 933 PM EDT THU MAY 26 2016

The line of showers has dissipated and the area is relatively
clear. Have updated to remove pops from the early tonight period.
The forecast issue through tonight will be cloud cover as any
breaks will allow fog to develop. Have put fog in the forecast and
also in the HWO for tonight. The other forecast problem tonight
will be the lifting of a warm front into the area. While weak and
vague due to convection earlier, this may provide enough forcing
for a few showers over the north to develop towards dawn.

UPDATE Issued at 618 PM EDT THU MAY 26 2016

Current conditions feature a weakening line of showers and
thunderstorms moving into eastern Kentucky. These storms will
continue with a weakening trend through the evening as they
continue to move into a more unfavorable environment. In fact, hi
resolution models indicate a complete dissipation by 06z. Have
adjusted the forecast to account for this and updated the current
obs as the rain cooled air has dropped temps across the area this
evening. Later tonight, a warm front looks to lift north through
the area as some weak forcing may be enough for a few showers to
develop over the north towards dawn. Have put in a slight chance
of showers for this possibility.


.SHORT TERM...(This evening through Friday night)
Issued at 359 PM EDT THU MAY 26 2016

Strong troughing across the southwest conus and ridging for the
southeast conus has led to SW to NE flow aloft across the
mississippi and Ohio River Valley. Several short waves continue to
eject ne along this flow and into the Ohio River Valley, including
the one that spawned a strong line of showers and thunderstorms this
morning over western KY and Illinois. This line has sustained itself
throughout the day and is now traversing central KY. Decent
instability present, along with good mid level drying, have led to
several of these storms going severe. Most of the hi res models have
had a fairly good handle on this system through the afternoon, with
preference for the HRRR which has been initializing well since this
morning. They also all have this line weakening as it moves into our
western CWA, then quickly dissipating as it moves east late this

Forecast soundings show good CAPE, LI`s -6 to -8, and steep lapse
rates. However our shear is lacking, and strong storms will likely
not be able to sustain themselves. As such, agree with models to a
certain degree. We could still see some isolated embedded cells that
could pop up to severe limits, or produce small hail at the least.
But do agree that there will be a diminishing trend as we head into
the evening.

By overnight, this line of showers and thunderstorms will move
eastward out of the region. High pressure will take hold, generally
to our southeast, leaving southerly flow across the region. The
continued moisture influx, in addition to the lingering moisture and
a night time inversion taking hold, could lead to fog development
across the CWA, especially in the valley locations.

High pressure will remain in control tomorrow. However southerly
flow will continue, allowing temps to easily climb into the mid and
even upper 80s by the afternoon. With that southerly flow will also
come moisture, so diurnal CU development will be likely. Afternoon
instability will also be in place, so scattered showers and
thunderstorms may develop for the afternoon.

.LONG TERM...(Saturday through Thursday)
Issued at 330 PM EDT THU MAY 26 2016

We begin the period more influenced by the upper level ridge
extending west out of the Mid Atlantic Coast, while upper level
closed low resides in the Central Plains states. Overall better
PVA will remain east of the region, but enough influence to
include some higher chance pops mainly toward the northern and
western portion of the CWA on Saturday and Sunday. Now moving into
the first part of the work week more uncertainty exists with
regard to waves and any residual down stream storm complexes that
hold together. Also another complication exists in the tropics
with potential for a developing tropical system near the Carolina
Coast line. Right now the GFS has been the most volatile with
little continuity run to run, while the ECMWF seems to be more
consistent. The influence from this overall should reside latter
portion of the long term period, therefore for now will stick with
model blend approach for now. This especially as shear will be nil
through the long period leading to little if any organization of
storms. Toward the very end of the period ridging breaks down more
allowing for more height falls. This will lead to higher chance
pops by Thursday given this looks to be the overall best synoptic
feature we have seen. Given the ridging a more summer time feel
will remain in place through the long term period.


.AVIATION...(For the 00Z TAFS through 00Z Friday evening)

Showers and thunderstorms moving through the area have begun to
dissipate and will likely be out of the area by 03z. Have adjusted
the TAFs to account for the dissipation of the activity. With many
locations seeing rain this evening, and a warm front lifting north
tonight, a few locations may see some breaks in the cloud cover
that will lead to some fog development. Have put fog in most TAFs
with a dissipation expected by 14z. The boundary stopping across
northern Kentucky tonight may lead to a few showers developing
towards dawn as well. Conditions should remain stable through the
morning before afternoon convection sets up again tomorrow
afternoon with the bulk of the showers and storms in the far east.
Winds will be relatively light through the period.


.JKL Watches/Warnings/Advisories...


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