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fxus64 kshv 171744 aac 

Area forecast discussion...updated
National Weather Service Shreveport la
1144 am CST sun Dec 17 2017

..text products are being resent to correct a temperature

Visibilities have improved across much of the area, so the dense
fog advisory was allowed to expire. The fog and thick cloud cover
have kept temperatures quite cool. High temperatures were lowered
areawide by a few degrees to account for the slower warming.

The 18z taf discussion follows below.


majority of the terminals still experiencing MVFR-IFR visible /with some
experiencing vlifr visible/, though conditions have slowly improved
since earlier this morning and should reach VFR criteria by this
afternoon. Furthermore, LIFR ceilings continued to plague all the
terminals and computer models are pessimistic with regard to showing
ceilings improve beyond MVFR criteria. Current thinking is that ceilings
will remain low thus have maintained a pessimistic taf cycle with
conditions improving to MVFR later this afternoon, but returning to
LIFR criteria this evening-tonight. Will of course amend as
necessary. In addition, an upper level disturbance approaching the
region from the west will aid in generating isolated to scattered
-shra commencing tomorrow morning, and moving in from south to
north /impinging on klfk and kmlu initially/. Have tried to insert
a vcsh and -shra with the appropriate time-frame.

Previous discussion... /issued 900 am CST sun Dec 17 2017/

dense fog with visibilities 1/4 sm or less have become widespread
across much of East Texas and western Louisiana along and south of
Interstate 20. Therefore, a dense fog advisory has been issued
through 17z this morning. Visibilities should slowly improve later
this morning.


Previous discussion... /issued 452 am CST sun Dec 17 2017/

one to two inches of needed rainfall occurred across the area last
night, with rainfall quickly exiting the area to the east by mid
morning. A very wet ground and easterly winds underneath a stg low
lvl inversion may result in a rather foggy morning for the Monday
am commute, with cloud cover being a possible limiting factor.
Another strong and fast movg upper low will pull the frontal
boundary responsible for this rain, back out of the Gulf as a warm
front on Monday. Pcpn water values this time around will greatly
exceed that with the system last night and very heavy rainfall
possible where this front will stall out on Tuesday, most likely
near or just north of the I-20 corridor. Expect some embedded
thunder as well with this widespread rainfall near and south of
this front. After a break in rainfall Wednesday into Thursday, a
strong upper low with plenty of cold air in its wake will come
barreling towards the area. Instability will become unseasonally
high with Li values in the negative across southern portions of
area and deep convection possible Thu night into Friday. Models
seem a little more progressive and thus tapering off pops into the
early weekend from the NW, which will ease concerns about
possible winter wx for any of the cwa prior to Christmas Holiday.
Although a trailing short wave with mid lvl moisture could produce
very lgt amounts of winter pcpn, mainly north of I-30, feel that
chances and possible impacts not significant to place mention that
far out in extended period attm.



Preliminary point temps/pops...
shv 60 47 66 56 / 10 10 30 60
mlu 60 47 65 55 / 30 10 30 60
deq 56 41 64 49 / 10 10 10 40
txk 55 44 64 53 / 10 10 20 50
eld 57 44 65 53 / 10 10 20 60
tyr 59 46 65 56 / 10 10 30 50
ggg 59 45 65 55 / 10 10 30 60
lfk 61 49 67 60 / 10 20 50 60


Shv watches/warnings/advisories...

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