Area Forecast Discussion
Issued by NWS Little Rock, AR
FXUS64 KLZK 250514 AAB
Area Forecast Discussion...UPDATED
National Weather Service Little Rock AR
1214 AM CDT Tue Apr 25 2017
Updated to include the 06Z aviation discussion below...
Mainly clear conditions will prevail for the majority of the TAF
cycle. However...some patchy fog may be seen at ADF. Lower clouds
will start to build back in towards the end of the period in
advance of an approaching system. Winds will be light and variable
tonight before increasing by mid morning and becoming gusty from
the south through the daylight hours. Even with the increasing low
level moisture...VFR conditions are expected to be dominant through
PREV DISCUSSION...(ISSUED 251 PM CDT Mon Apr 24 2017)
SHORT TERM...Tonight Through Wednesday
Dry and warm conditions will prevail during the first half of this
period. Breezy conditions are expected on Tuesday afternoon, as a
south-southeasterly wind field increases in response to developing
surface low pressure across the central plains. Warm conditions
again expected on Tuesday, with afternoon temperatures expected to
average ten degrees above normal.
Conditions are expected to become active late in the period. Energy
now approaching the Pacific northwest coast is expected to amplify
as it moves east-southeastward. Low level southerly flow is forecast
to transport substantial moisture to the region. A cold frontal
boundary is expected to approach by early Wednesday, and will
provide a pronounced focus for convection. Analysis of forecast
Q-vectors indicates a large dynamic response to affect the
atmospheric column across the mid south. Together with the frontal
forcing, conditions will favor the development of a linear type
MCS, with damaging wind gusts to primary threat with thunderstorms
LONG TERM...Wednesday Night Through Monday
Main area of concern over the extended term is the potential for
severe weather on Friday, Saturday, and again on Sunday.
Warm front will be surging northward on Friday, with a broad
midlevel trof across the area. SE flow at the surface with a
westerly to SW flow aloft will make for a decent amount of
directional shear. Certainly concerned about the potential for
tornadoes with this system.
Warm front will become quasi-stationary across the northern part of
the CWA on Saturday, or possibly just north of the area. The models
are having quite a bit of difficulty deciding just where this system
is going to stall out. By Saturday afternoon into Saturday night, a
cold front will start pushing into the area, and I would anticipate
this will result in a squall line moving across the area. It is a
bit far out to determine if there will be any discrete supercells
ahead of the squall line, but in setups like this I am certainly
concerned about that possibility.
By Sunday the focus will shift into eastern AR as the system pushes
out of our forecast area.
Models show PWAT values up to an inch above normal as the warm
sector surges over us on Friday. With slow moving frontal systems,
and the potential for training thunderstorms, there will certainly
be a risk for flooding and/or flash flooding during this time frame.