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fxus64 kshv 120524 

Area forecast discussion
National Weather Service Shreveport la
1124 PM CST Mon Dec 11 2017

VFR conditions are expected throughout the taf cycle. The few-scattered
VFR ceilings that were affecting the terminals earlier this evening
has since exiting the region resulting in sky clear. Wind speeds will
stay up a bit overnight across most of the taf sites /5-12 kts/
whilst a cold front moves across the terminals after midnight thus
veering winds to the northwest. Breezy conditions will commence
mid-morning with expected sustained wind speeds of 8-15 kts with
higher gusts /15-19 kts/, before a notable declination occurs by
late afternoon /dropping to or below 10 kts/.


Previous discussion... /issued 948 PM CST Mon Dec 11 2017/

an upper trough axis diving southeast across the plains and mid
Mississippi River valley is helping to push a cold front south
across the Southern Plains. At 03z, the front was still well to
the north of the County Warning Area in Oklahoma and Arkansas, but a pre-frontal
surface trough is approaching the Interstate 30 corridor. Surface
winds will shift to the northwest with the passage of this trough
and increase in speed.

The increased northwest flow will advect lower dewpoints into the
region. However, surface observations suggest the cooler air
still lags far to the north. Temperatures behind the front in
eastern Oklahoma are just barely below 50 degrees f. The lack of
strong cold air advection will somewhat limit how fast we cool
tonight. In addition, some increased high level cloud cover
across Texas and Louisiana may also keep temperatures a couple of
degrees warmer. Therefore, the primary update tonight was to
increase the minimum temperature forecast for tonight/Tuesday
morning by a few degrees areawide.

Updated text products have already been sent.


Previous discussion... /issued 306 PM CST Mon Dec 11 2017/

Short term /tonight through Tuesday/...

A cold front currently analyzed across northwest Arkansas into
southeast Oklahoma and north central Texas will continue moving
south and east into the four state region this evening into the
overnight hours. Temperatures have warmed well into the 70s
areawide this afternoon and with Post frontal conditions expected
overnight, there should be sufficient mixing to allow for another
cool night tonight but perhaps not as cold as if we had ideal
radiational cooling conditions expected as has been the case the
last several nights. Still, undercut MOS temperatures a few
degrees in a few locations to account for the dry airmass in place
as guidance has been running too warm with overnight low
temperatures lately

Stayed near to slightly warmer than MOS temperatures concerning
daytime highs on Tuesday as well. Northwest winds on Tuesday near 10
to 15 mph with some higher gusts in the morning from a tight
pressure gradient. 13

Long-term /Tuesday night through Monday/...

Colder air behind tuesday's cold front will push overnight lows back
into freezing territory for Wednesday morning. Winds will quickly
veer back SW during the day Wednesday and allow for a modest warm-up
as highs warm back into the lower to mid 60s. Another dry cold front
will arrive on Thursday with simply no moisture available with such
a brief period of return flow between fronts. Cooler temperatures on
Friday will be short-lived as southerly winds return in time for the
weekend. Increasing SW flow at the sfc and aloft by late Saturday
will present our best chance for rain during this forecast period.
This will be occurring ahead of another cold front shifting through
the plains, tapping into Pacific moisture associated with an upper
disturbance near baja. SW flow will help usher in more of this mid
and upper level moisture ahead of the cold front with the best rain
chances across the southeast half of the region but have at least included
slight chance pops even over our northwest zones. Rain chances will wrap up
from the northwest to southeast with frontal passage on Sunday through the evening
hours. A dry and mild forecast will prevail behind the front for the
new work week with temperatures running near to just slightly above
normal. 19


Preliminary point temps/pops...
shv 41 59 34 63 / 0 0 0 0
mlu 41 59 32 60 / 0 0 0 0
deq 34 55 28 64 / 0 0 0 0
txk 38 55 32 63 / 0 0 0 0
eld 37 57 31 61 / 0 0 0 0
tyr 41 58 34 65 / 0 0 0 0
ggg 40 59 32 64 / 0 0 0 0
lfk 39 63 33 62 / 0 0 0 0


Shv watches/warnings/advisories...

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