Scientific Forecaster Discussion
fxus64 klch 190840
Area forecast discussion
National Weather Service Lake Charles la
340 am CDT Sat Aug 19 2017
late night sfc analysis shows the area mainly under the influence
of high pressure centered over the nwrn Gulf. Water vapor imagery
shows a shortwave crossing the middle Mississippi Valley which is
helping dig a trof over the ern conus, while closer to home weak
ridging is noted from the Desert Southwest through the srn plains.
Satellite imagery/sfc obs indicate generally clear skies over the
forecast area. Regional 88ds are mostly quiet, save for some dying
outflow-induced convection far to our northeast.
All signs point to today being another hot and mostly dry day
across the forecast area, thanks to lingering ridging in place
mainly to our west. Best pops again look to be across the ern
extremes of the area where forecast soundings indicate best
moisture/least capping...and even then, we're still looking at
just low end chance pops at best. Main story remains the heat as
Max temps this afternoon are progged to reach well into the mid
90s especially over the wrn 1/2 of the area. With dewpoints
running in the mid 70s over much of the area, apparent temps
currently top out at 105...even if these wind up a little lower
than values actually recorded this afternoon, it looks as if the
local 108+ criteria should remain out of play and thus no heat
advisory appears needed for today.
Any convection which develops today should diminish with
sunset/loss of heating this evening...with overnight weather
looking dry for now.
Sunday looks like a general repeat of today albeit with slightly
better pops over the wrn 1/2 of the forecast area as a little
better moisture is noted on forecast soundings. Still our resident
ridging aloft should keep somewhat of a limit on convective
development. Heat index values again remain just below advisory
criteria...will definitely give this another look tomorrow night.
A mid/upper-level low currently seen on water vapor imagery over
the Florida Straits is progged to push slowly wnwwd over the next
few days which could begin to impact our weather, particularly as
we head toward the middle of next week. Rain chances begin to
increase by Tuesday/Wednesday as the low approaches. Pops further
increase late in the period as a frontal boundary moves into the
no flags are anticipated on the coastal waters through the period
with high pressure remaining generally in control.
Preliminary point temps/pops...
aex 94 75 93 75 / 30 20 30 10
lch 94 78 93 78 / 20 20 30 10
lft 94 77 94 77 / 20 20 30 10
bpt 95 76 93 77 / 10 10 30 10