884
FXUS64 KLCH 201117
AFDLCH

Area Forecast Discussion
National Weather Service Lake Charles LA
617 AM CDT Thu Aug 20 2026

...New AVIATION...

.KEY MESSAGES...

- A Heat Advisory is in effect until 8 PM today for indices up to
  110F. Another advisory has been issued area-wide from 12 PM to 8
  PM Thursday, also for indices up to 111F.

- Heat Stress Levels will increase to Extreme (level 4 of 4) from
  southeast Texas to all of Louisiana by Friday. Extreme Heat Risk
  levels will persist into next week.

- Upper ridge will remain in place keeping afternoon highs above
  normal with no appreciable rainfall through the next seven
  days.

- Vegetation will continue drying with these conditions. Check
  with your local officials for burn bans across SETX and CEN/SWLA.

&&

.DISCUSSION...
(Tonight through next Wednesday)
Issued at 1148 PM CDT Wed Aug 19 2026

Hot weather remains our main concern with afternoon highs
expected to be in the upper 90s to triple digits for the rest of
the week and into the weekend. While the 500 mb ridge has started
to move westward we are still looking at a persistence-driven
regime with little change in the day to day weather. While troughs
along the periphery of the ridge can create conditions for
widespread convection or even severe weather, we are still too
close to the center of the ridge to see any widespread
thunderstorms or showers. But the lowering heights along with
weaker subsidence will lead to a slight uptick in afternoon
showers and thunderstorms with PoPs around 30% in Acadiana due to
higher moisture content and weaker ridging. PoPs drop down to 10%
in southeast Texas. With peak daytime heating surface based CAPE
values are averaging around 4000 J/kg with DCAPE values near 1000
J/kg. These values support the possibility for pulse-microbursts
with damaging downdrafts as the popup showers and thunderstorms
fall apart.

As stated previously the main concern will be dangerous heat with
an area wide heat advisory for Thursday. Heat index values will be
between 108 and 110 F. The heat risk will be Major to Extreme
(Level 3 or 4 of 4) make sure to take breaks from the heat and
stay hydrated!

&&

.AVIATION...
(12Z TAFS)
Issued at 617 AM CDT Thu Aug 20 2026

Light SW/SSW winds around 3-8 kts and VFR ceilings/vis will
prevail through the forecast period.

&&

.MARINE...
Issued at 1148 PM CDT Wed Aug 19 2026

High pressure continues to dominate our weather pattern. Winds
will remain light and mainly onshore with winds speeds between 5
and 15 knots. Waves will remain below 3 feet for the next several
days.

&&

.FIRE WEATHER...
Issued at 1148 PM CDT Wed Aug 19 2026

Hot and dry weather will continue with no widespread wetting rain
in the forecast. MinRH values will be between 30 and 40% in the
afternoon with MaxRH rebounding into the 90s overnight. With the
ongoing dry conditons KBDI values are now in the 600 to 700 range
area wide. The main limiting factor for increased fire weather is
a lack of winds with wind speeds staying below 10 mph.

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory from noon today to 8 PM CDT this evening for
     LAZ027>033-044-045-055-073-074-141>143-152>154-241>243-
     252>254.

TX...Heat Advisory from noon today to 8 PM CDT this evening for
     TXZ180-201-259>262-515-516-615-616.

GM...None.
&&

$$

PUBLIC/FIRE/MARINE...14
AVIATION...17