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Area forecast discussion 
National Weather Service Shreveport la
242 PM CDT Thursday may 28 2015

Discussion...
convection late this afternoon tied to instability and residual
boundaries left over from the morning mesoscale convective system which moved across the
middle Red River valley of northern Texas and southern Oklahoma.
Outflow boundary currently resides from near Sulphur Springs and
Mount Pleasant to near Texarkana and El Dorado Arkansas...moving
very slowly southward. Slightly stronger capping inversion is
inhibiting storms from forming along the Texas portion of the
boundary but temperatures are near 90 south of the boundary at this time
so would not be surprised to see a few strong to severe
thunderstorms form on this boundary before convection begins to
die off later this evening.

Visible satellite imagery showing our next weather maker taking
shape across the Texas Hill country. This convection in association
with an upper level trough that is likely to traverse across the
state of Texas overnight tonight. Short term forecasts are in pretty good
agreement with the development of this system and its progression
eastward overnight with the exception of the GFS which for some
reason looses it after sunrise on Friday. The hrrr seems to have
the best handle on this convection after midnight approaching the
I-35 corridor of north/c Texas and eventually moving into our western
zones during the predawn/dawn hours. Therefore...have oriented
higher chance probability of precipitation after midnight in the west with slight chance
variety in the east. All forecasts have this well defined upper trough
axis in the vicinity of the I-35 corridor to our west on Friday
and with plentiful moisture in place not to mention divergent flow
aloft...have increased probability of precipitation to likely across our western two
thirds for Friday. This trough axis slowly moves its way eastward
into NE Texas/SW Arkansas/northwest la Friday night/Sat and stalls out. Cold front at
the surface in association with this upper trough moves our way and
stalls out Sat night/sun as well somewhere across our County Warning Area and will
serve as a focus for additional shower and thunderstorm development...
mainly across our southeast zones Sun night through early next
week.

There continues to be more and more consistency with each new
model run that this stagnant upper level trough will become
cutoff from the westerlies by the early to middle portion of next
week. Just where this occurs in relation to our vicinity could
result in a very wet work week next week...to only widely
scattered variety storms. For now...will keep the extended pop
grids consistent with previous forecasts with higher probability of precipitation across
our eastern zones next week with slight chance variety in the
west. It must be noted that if this trough cuts off to our
west...then much higher probability of precipitation would be the end result for a much
larger portion of our area next week.

Temperatures should be slightly milder this upcoming weekend given
the expected storm coverage with below normal temperatures through
at least the early portion of next week before we begin to see
some recovery by late next week.

Prelims to follow...13.

&&

Previous discussion... /issued 100 PM CDT Thursday may 28 2015/

Aviation...
for the 28/18z tafs...scattered convection ongoing this afternoon
across the region but most terminals have dodged thus far...aside
from thunderstorms in the vicinity at shv/txk. Expect additional showers/thunderstorms through the
remainder of the afternoon and into the evening but coverage is
still not enough to warrant any more than thunderstorms in the vicinity at this time...so will use
amendments if necessary for thunderstorms and rain. Winds to remain rather light and
somewhat variable at times...with a predominant south direction
for much of the period. Clouds will be layered with increasing cumulus
this afternoon along with some middle and high clouds mixed in as
well. Convective debris clouds will likely linger overnight with
low stratus returning closer to daybreak along with patchy fog and
reduced visibilities. /19/

&&

Preliminary point temps/pops...
shv 71 86 69 83 / 30 60 50 60
mlu 69 88 69 84 / 30 50 50 60
deq 67 82 67 80 / 40 60 50 60
txk 69 84 68 82 / 30 60 50 60
eld 67 86 69 82 / 30 50 50 60
tyr 72 83 69 82 / 40 60 50 60
ggg 72 85 69 83 / 40 60 50 60
lfk 71 86 70 86 / 40 60 50 60

&&

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

$$

19/13

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