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Area forecast discussion
National Weather Service Shreveport la
415 PM CDT Wed Sep 18 2019

Short term.../tonight through Thursday night/

The remnants of tropical depression Imelda continue to lift north
into East Texas this afternoon with bands of showers and embedded
thunderstorms spreading across much of the region. This has been
enhanced by daytime heating, especially across the northern and
eastern sections of the area where temperatures climbed into the
lower to mid 90s this afternoon. Farther south and west near the
center of circulation around the remnants of Imelda, temperatures
have been held mainly in the lower 80s across deep East Texas with
mid and upper 80s farther north along the I-20 corridor eastward
into northwest Louisiana.

Decent coverage of convection is expected to continue through the
remainder of the afternoon with activity generally coalescing
closer to the center of circulation through this evening and
overnight over much of East Texas and western Louisiana. Overall,
rainfall rates have been very manageable thus far but that is
expected to become more problematic over the next 24-36 hours as
heavier bands of rainfall set up and train across parts of the
region. As a result, have expanded the Flash Flood Watch in time
and coverage, taking in more of East Texas and northwest Louisiana
generally along and south of the I-20 corridor. On average,
rainfall amounts should range from around 3-7 inches in the watch
area with isolated higher amounts of 8-10+ inches possible through
Friday morning, primarily across deep East Texas into Toledo Bend


Long term.../Friday through Wednesday/

The remnants of Imelda should be falling apart quickly through the
course of Friday as moisture begins to pull north toward a frontal
zone dropping into the Central Plains and Midwest. That said, there
could still be some pockets of heavy rain around the northern half
of the arklatex through the morning hours, but by afternoon the
precipitation activity should be scattered in nature. Temperatures
should be held down below 90 degrees due to lingering clouds and
showers, but expect plenty of moisture around to boo1st heat index
values well above the actual temperature.

The forecast has not changed a great deal regarding expectations for
this weekend and through the early portion of next week. In short,
the front alluded to above should run out of the steam on its
southward journey by the time it approaches the northern portions of
the four state region. This boundary could be a trigger for at least
isolated showers and storms well north of I-20 Sunday night through
Tuesday and temperatures in the northern quarter of the region could
be knocked down a bit if the front makes slightly more progress than
expected. Otherwise, anticipate temperatures warming back to above
normal levels through the weekend and remaining in that neighborhood
through early next week. Away from the potentially-stalled boundary
in the north, expect only very isolated and diurnally-driven showers
and storms, at best.



Previous discussion... /issued 154 PM CDT Wed Sep 18 2019/


Increased pops to high chance up to the I-20 corridor in northwest
Louisiana given the current radar trends. Otherwise, no other
changes needed at this time. See below for aviation discussion.


For the 18/18z taf period, increasing cloud cover and lowering
cigs will continue through this period as the remnants of dew point
Imelda lift northward into East Texas. Low VFR/MVFR cigs will be
common at nearly all sites through much of the period with the
exceptions of eld/mlu where lower clouds will be later arriving.
Bands of moderate to heavy showers and embedded thunderstorms
will continue to expand northward through period in association
with dew point Imelda. Vsbys may be reduced to MVFR/IFR at times with
heavier showers/t'storms. Otherwise, expect east/southeast winds to prevail
around 6-12 kts with higher gusts at times, especially near areas
of convection. Cigs will likely drop to to IFR late in the period
as the low pressure circulation with dew point imelda's remnants shifts
north across the region.



Preliminary point temps/pops...
shv 73 83 71 83 / 50 80 90 60
mlu 72 89 71 88 / 20 40 60 40
deq 71 89 70 81 / 20 40 60 80
txk 72 85 70 79 / 20 50 80 70
eld 71 88 70 82 / 20 40 80 50
tyr 72 81 71 85 / 60 70 60 70
ggg 72 81 71 83 / 60 80 90 70
lfk 73 81 73 85 / 90 90 70 50


Shv watches/warnings/advisories...
La...Flash Flood Watch through Friday morning for laz001-002-010-011-

Texas...Flash Flood Watch through Friday morning for txz126-136>138-


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