FXUS64 KLZK 211129
Area Forecast Discussion
National Weather Service Little Rock AR
529 AM CST Wed Nov 21 2018
Difference in air temperature and the water temperature of local
lakes and rivers has resulted in areas of freezing fog this
morning, which is quite evident on satellite imagery at this
time. There could be some travel impacts this morning especially
on the longer bridges and overpasses that span these water ways.
An SPS was issued for a few hours to cover this concern. Fog will
dissipate by mid morning,
Patchy fog will be possible for a few hours this morning at KHOT
and KLIT before it does burn off by 15Z. The fog will result in
occasional IFR conditions. VFR conditions will return to all
terminals by mid morning and remain in place as high pressure
dominates. Winds will be light and southerly.
.PREV DISCUSSION...(ISSUED 300 AM CST Wed Nov 21 2018)
Short term...Today through Thursday night
Latest surface analysis places high pressure squarely on top of the
state with virtually no wind and barely a cloud to speak of. As
such, conditions are ideal for radiational cooling and temperatures
have dropped into the mid 20s through lower 30s. A little patchy fog
is also showing up in the usual locations but not nearly to the
extent it was last night with dry air mass in place.
High will drift to the east today and provide the area with mostly
sunny skies. Weak return flow will be getting established later
today on the back side of the anti-cyclone with high temperatures in
the mid to upper 50s expected.
Upper pattern features upper ridging over the northern Rockies with
broad cyclonic flow over the northeast quad of the country. Pattern
is fairly progressive with split flow regime developing with time. A
weak wave embedded in the southern branch will pass well to the south
of the state on Thanksgiving with only some high level clouds to
mark its presence. Southerly flow will be more established Thursday
with temperatures topping out a few degrees on either side of 60.
Aforementioned return flow does pull in some gulf moisture Thursday
night as a stronger wave approaches from the west. Latest modeling
suggest that cloud cover will increase steadily Thursday night with
maybe an isolated shower over the very far west by the end of the
period. Main impact from this wave will be felt in the extended
Long term....Friday through Tuesday...
A fast moving shortwave trough will be moving east across the state
at the start of the long term period...with widespread SHRA expected
on Fri. Some TSRA may also be possible...but the threat for any
strong storms will be minimal. Rainfall amounts will be generally
less than one-half inch...though some locally higher amounts closer
to an inch will be possible...mainly over NERN sections of the CWA.
Temps will drop below normal for Fri highs due to the rainfall and
This system will move east of the state by Sat...with weak upper
level ridging over the region to start the weekend. Temps will warm
to just above normal for Sat as a result...with dry conditions
expected. Another...stronger upper level shortwave will drop SE into
the Plains from the Rockies on Sun...with a cold front moving east
across the state by Sun afternoon. Latest guidance keeps suggesting
moisture levels decreasing with this late weekend storm
system...with little to no QPF forecast for the CWA. As a
result...have continued to trend POPs downward...but still keep some
slight chance POPs for SHRA along/ahead of the front. Most precip
will remain north of AR.
By early next week...cooler air will filter back into the
region...with temps dropping back below normal to wrap up the
forecast. Precip chances will remain low also...with upper level
flow over the region generally from the NW.
Short Term...GOUDSWARD / Long Term...62