Area Forecast Discussion
Issued by NWS Little Rock, AR
FXUS64 KLZK 240505 AAA
Area Forecast Discussion...UPDATED
National Weather Service Little Rock AR
1105 PM CST Thu Feb 23 2017
It appears now that moisture return ahead of an approaching cold
front will likely be enough to produce widespread MVFR ceilings
across central and southern Arkansas late during the morning hours
on Friday. Have added these to the 06z TAF package accordingly, with
3-6 hours of MVFR ceilings expected around 13z for KLIT and points
southeast. KHOT and KADF may be just far enough west that developing
MVFR ceilings will not quite make it in there before a dry line
pushes into west-central Arkansas ahead of the cold front. Up north,
have included some VCSH at KHRO as some scattered elevated
convection has shown up. Otherwise the main forecast issue up north
will be low-end MVFR ceilings pushing into the north behind the cold
front, and this has been addressed in the forecast.
.PREV DISCUSSION...(ISSUED 218 PM CST Thu Feb 23 2017 )
Short term...Tonight through Saturday night.
Not a lot of value added changes will be forth coming this afternoon
as short term models are in good agreement with each other and with
what is in our current forecast.
Upper pattern is currently quite progressive in nature with an upper
level low off the eastern Florida coast and a broad upper trough
over the intermountain west. This has resulted in ridging over the
southeast CONUS and strong southerly flow. This upper pattern along
with surface low pressure now developing over western Kansas has
resulted in a tightening pressure gradient along with breezy and
very warm conditions. Fog dissipated quickly over the area this
morning and only some high clouds are passing by as a weak
disturbance passes to the north. With this same set up continuing
tonight, lows Friday morning will be mild once again.
Aforementioned surface low will race off to the northeast and drag a
front across the state on Friday. No precipitation is expected with
this feature as the Gulf of Mexico is essentially closed right now
and deep moisture will not make it in here. Winds will remain on the
breezy side with this frontal passage and humidity will decrease
rapidly in its wake. However, winds will fall just short of lake
wind advisory criteria and no fire weather highlights are expected
but wildfire danger will be elevated.
High pressure will build in behind the front with breezy conditions
subsiding after dark. Colder air will follow the front as well, with
freezing temperatures possible in the northwest and west by early
Saturday morning. The high will dominate Saturday with temperatures
a bit on the cooler side but winds will be returning back to the
south as the period ends.
Long Term...Sunday through Thursday night
Long term starts with near zonal flow aloft and a surface high
pressure centered to the east of the state. Southerly winds at the
surface will result in temperatures returning to above normal on
Sunday afternoon after a cold start to the day.
Clouds and rain chances will increase on Sunday as high pressure
shifts to the east...allowing a storm system to approach from the
west. Rain will continue through much of the day on Monday with
chances tapering off through the afternoon hours.
From here...the models begin to diverge a bit on Tuesday. The latest
GFS keeps precipitation cut off to the south of the state along a
stalled front. This is a change from previous runs...and therefore
will lower POPs a tiny bit...while still leaning towards the more
Precipitation chances end across the state during the first half of
the day on Wednesday with near normal temperatures returning to the
state to round out the long term.
Breezy conditions are expected Friday with a cold front moving
through. Humidity values will drop rapidly after the front and
into the 20th percentile over most of western Arkansas. Conditions
look to fall just short of red flag criteria but fire danger will
remain elevated. Fine fuel moisture is expected to remain above