Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Shreveport la
531 am CST Monday Dec 22 2014

Aviation...
IFR/LIFR ceilings this morning to gradually improve to MVFR this
afternoon. A cold front will move across the region later this
evening allowing for clearing skies from the west. South winds 10
knots expected across Louisiana and Arkansas terminal sites today...
with 15 knots and gusty possible across East Texas sites. Winds to
become northwest after 23/06z as cold front moves across the
region. /05/

&&

Previous discussion... /issued 350 am CST Monday Dec 22 2014/

Discussion...
a couple of shortwave troughs will move across the Southern Plains in
advance of a much stronger upper trough that will affect our
region beginning on Tuesday. There could be a few scattered showers this
morning associated with these lead shortwaves mainly across the
NE half of the County Warning Area. Southerly flow will increase today in response to a
sharpening cold front to our northwest and Lee cyclogenesis over the High
Plains. This should allow temperatures to warm into the 60s across much
of the area today despite quite a bit of cloud cover. I would not
be surprised to see some locations across deep East Texas/central la flirt
with 70 degrees f this afternoon.

Aforementioned upper trough will strengthen and dig sharply southeastward
into the Southern Plains by Tuesday morning. This will drive a cold
front quickly through the County Warning Area. Rain chances will begin to increase
tonight and look to be very good east of a line from klfk to
Prescott Arkansas for Tuesday...probability of precipitation will increase farther east. Vast
majority of the rain will be Post-frontal which should keep any
severe weather chances minimal. Opportunities for convection
should be low as well but a surface low will develop along the Texas
coast and then lift northeastward along the front. Elevated instability due
to the proximity of the surface low and the cold core upper trough may
be sufficient to support a few embedded thunderstorms during the day
Tuesday south of a Nacogdoches-Monroe line.

Precipitation will gradually exit the area by Wednesday morning. Effects
and speed of dry slotting are still very much in question during
this time period as the surface low lifts northeastward into the Tennessee River
valley. Cold air aloft with the upper trough combined with northerly
flow in the low/middle levels may result in enough cooling to support a
light rain/snow mix across the terrain of southeast OK/SW Arkansas before all
the precipitation ends. This is still quite uncertain but only trace
amounts are expected if any wintry precipitation occurs and impacts
should be minimal.

After a chilly day and night for Wednesday...shortwave
ridging...abundant sunshine...and southerly flow will allow temperatures to
warm back to near or slightly above normal levels for Thursday and
for most of the area on Friday. Yet another upper trough and cold
front will affect the region going into next weekend. GFS and
European model (ecmwf) are in quite a bit of disagreement regarding this system.
The European model (ecmwf) is more aggressive and considerably wetter and its forecast
does reflect well the behavior of the last few major storm
systems. However...both models are shown poor run-to-run
consistency so will only go with slight chance probability of precipitation for next
Saturday. /09/

&&

Preliminary point temps/pops...
shv 66 49 55 38 49 / 20 20 50 30 10
mlu 66 50 59 39 51 / 30 30 70 60 10
deq 60 41 53 32 47 / 30 20 40 20 10
txk 62 46 53 36 47 / 30 20 40 20 10
eld 62 46 55 36 49 / 30 30 50 40 10
tyr 65 47 52 38 48 / 20 20 40 10 10
ggg 66 47 53 37 49 / 20 20 40 20 10
lfk 69 51 57 38 50 / 20 20 40 20 10

&&

Shv watches/warnings/advisories...
Arkansas...none.
La...none.
OK...none.
Texas...none.
&&

$$

05/05/05

National Weather Service Glossary of Abbreviations