Area Forecast Discussion
Issued by NWS Little Rock, AR

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FXUS64 KLZK 201825

Area Forecast Discussion
National Weather Service Little Rock AR
1225 PM CST Mon Feb 20 2017


For the 18Z TAFs...

A large upper level trough will move east across Arkansas from
this evening through the overnight hours. All available model
guidance shows numerous showers moving across the state between 00
and 12z. The consensus of guidance indicates that rainfall will be
heaviest and most persistent across central and south Arkansas.
The best window of opportunity for heavier rain in central and
south Arkansas is from 02 to 08Z.

Before 00Z...Rain chances will remain low...but non-zero. Isolated
showers are possible across the state this afternoon...but are a
bit more likely across northwest Arkansas than elsewhere. After
00z, rain showers will increase in coverage.

While it is raining this evening and through tonight...visibility
will likely fall to IFR levels with ceilings hovering right around
1,000 feet AGL. Rainfall totals are likely to remain below 1 inch
tonight...but 3-4 hours of persistent rainfall is possible as the
upper level trough/storm system moves in.

Winds are expected to veer to the west-northwest as the upper
trough approaches as a weak Pacific-type cold front moves across
the state ahead of the heaviest rainfall. Winds will become light
and variable by sunrise and visibility and ceilings will improve
towards VFR conditions before noon.




Forecasts account for trends in expected convective development. Expect
additional MVFR cigs to develop after 06z across most sites.



SHORT TERM...Today Through Tuesday Night
Main forecast challenges during this period are QPF and timing of
the upcoming precipitation event.

Latest water vapor imagery continues to indicate the eastward
progression of an upper trough approaching the Big Bend area,
along with nearly phased, smaller amplitude energy pushing into
the central plains. Convection currently is occurring ahead of
these systems, from southern Texas to eastern Kansas.

The upper system(s) will continue eastward during this period,
with the southern system weakening with time. Overall coverage and
intensity of associated precipitation is expected slowly decrease,
at the systems lose their phased nature, and stronger convection
to the south of the forecast area affects moisture transport to
the region. Precipitation is expected to be east of the forecast
area by 00z Wednesday.

Above normal temperatures will continue during this period.

Long Term...Wednesday through Sunday
The period will begin with dry and very warm conditions on
Wednesday. Temperatures will be well above average.

A storm system will ride the southern stream through the central
Plains toward the upper Midwest Thursday and Friday. It will
continue to feel like spring. At the surface, low pressure will
deepen quickly to the north of Arkansas. There should be a lot of
wind surrounding the system, with gusty south/southwest winds
shifting to the west as a cold front pushes through the state.

Data is showing limited moisture/capping ahead of the
front, with little in the way of precipitation. If we
get any more instability/less capping, would think there
would be better chances for thunderstorms as the front
goes through. But, for now, have slight chances of thunder
in the eastern counties on Friday.

Cooler weather will follow by the beginning of next weekend.
Temperatures will be closer to seasonal. As the weekend comes to a
close, a new storm system will approach from the southern Plains.
Clouds will increase, with chances for showers and thunderstorms
on Sunday.


.LZK Watches/Warnings/Advisories...NONE.


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