Area Forecast Discussion
Issued by NWS Jackson, KY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KJKL 061140 AAA

National Weather Service Jackson KY
640 AM EST Sat Mar 6 2021

Issued at 630 AM EST SAT MAR 6 2021

Have just touched up the near term grids per the latest obs and
trends for the T/Td ones. These updates have been sent to the NDFD
and web servers.


.SHORT TERM...(Today through Sunday)
Issued at 510 AM EST SAT MAR 6 2021

09z sfc analysis shows high pressure building into the state from
the northwest. This is working to clear the high clouds found over
the southern 2/3rds of the area from a sfc wave passing by to the
south. Temperatures vary generally from north to south with the
clouds but also by terrain tonight with a small ridge to valley
split in place. Mid 20s are found north and in those valleys
beneath the thinner clouds while the low 30s are noted on the
ridges and in the south with the thicker clouds. Dewpoints,
meanwhile, are generally from the upper teens on the ridges to the
mid 20s in the valleys. Winds are mostly light from the north
early this morning with the dry air and clouds are keeping the
fog away.

The models remain in pretty decent agreement aloft through the
short term portion of the forecast. They all depict the sharpening
of a large northeastern trough locally tonight into Sunday
morning as a healthy mid level energy impulse dives through
eastern Kentucky. The ECMWF and NAM are a tad stronger with this
wave than the GFS, though a dry column of air will make this
distinction immaterial for actual impacts. Quickly, this node of
the trough moves on to the east with weakening northwest flow over
the JKL CWA to follow into Sunday evening. Given the relatively
small model spread will again favor the NBM for the bulk of the
grids, though significant adjustments were made to both dewpoint
and temperatures through the period per recent trends.

Sensible weather will feature very dry conditions through the
weekend as dry air is reinforced by high pressure building into
the area as well as a dry layer aloft that will be brought down to
the sfc due to deep mixing. Otherwise, just a matter of some high
clouds moving by to the south today and clear conditions tonight
and Sunday. This will promote good radiational cooling and likely
a moderate ridge to valley temperature difference by dawn Sunday.
Per similar situation yesterday, have dropped the dewpoints in
the early afternoon today and Sunday resulting in lower min RH
values - important for the prescribed fire weather forecasts.
Also took temps up a degree or two both days for highs.

As previously mentioned - did open up a larger ridge to valley
temp split tonight rather than the NBM guidance and also took
down the dewpoints with good mixing. Again the PoPs were zeroed
out for simplicity given the minimal guidance values.

.LONG TERM...(Sunday night through Friday)
Issued at 445 AM EST SAT MAR 6 2021

High pressure and much warmer weather will both be the name of the
game in the extended. Highs each day should max out in the 60s,
with the warmest day being Thursday, when highs are expected to
top out in the upper 60s for most locations. Nightly lows should
be mainly in the 40s and lower 50s. Rain chances may return by the
end of the week, as a slow moving frontal boundary tries to make
its way south toward our area. The best rain chances would be for
locations along and north of the Mountain Parkway, nearer to the
front. Aside from that, the majority of the extended should be
warm and dry.


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)

VFR conditions dominate, and will continue to do so, through the
entirety of the period. Look for some high clouds around from time
to time. Winds are currently light, but are expected to increase
slightly this afternoon, though generally staying below 10 kts -
becoming light again after sunset.




AVIATION...GREIF is the U.S. government's official web portal to all federal, state and local government web resources and services.