Flash Flood Warning 8, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
327 AM CDT Wed Aug 24 2022

...New SHORT TERM, LONG TERM, AVIATION, MARINE...

.SHORT TERM...
(Today and Tomorrow Night)
Issued at 236 AM CDT Wed Aug 24 2022

Weak/diffuse frontal boundary should be situated across the northern
1/3 of the CWA today. Deep Gulf moisture with PW's in the 2.2-2.5"
range will be pooling along and south of this feature. Combined with
heating and subtle impulses embedded in the flow aloft, this should
bring good chances for shra/tstms across parts of the region
today...particularly south of a Livingston-Columbus line. Steering
flow is very weak. In addition, potential is there for some training
with disturbances generally riding parallel to the frontal boundary.
Will need to keep a close eye on things...as efficient rain rates
are anticipated given the moisture profile. It looks like one of
those days where a swath of 0.5-1.0" accumulations will be the norm
across southern parts described above, but with some very localized
2-5" mixed in if and where any clustering/training occurs. Grounds
should be able to handle a good amount of precip...just not the 2-
3"+/hr rates which would cause some street flooding. Will handle
this potential by adding the mention of locally heavy rainfall into
the fcst/grids for now.

Looking for rains to mostly taper off toward evening, followed by
some regeneration later tonight closer to the coast. Parameters for
Thurs look about the same as today, but llvl boundary will probably
set up a touch further south...so axis of better rain chances should
follow (maybe I-10 to the coast assuming no significant mesoscale
disruptions in the meantime).

47

&&

.LONG TERM...
(Friday through Tuesday)
Issued at 236 AM CDT Wed Aug 24 2022

Spoiler: Wet weather persists through the long term.

A weak upper level low will be hanging around the northwest Gulf
Friday through Tuesday which combined with PWATs near 2 inches
will lead to continued chance of precipitation. Generally the best
chance for showers and thunderstorms will be during the morning
through late afternoon hours with coverage shrinking during the
overnight periods. Through the start of next week, the best chance
for precipitation will be along and south of I-10, but exactly
where the storms develop will be driven by mesoscale features (sea
breeze, out flows, etc.) that can't be predicted this far out. On
average, expect up to 1 to 2 inches of rain through Monday with
the chance for locally higher or lower amounts. There may be a
pattern change as we get towards the end of the long term as a
slow boundary moves in from the north. Exact timing on this is
uncertain, but should happen Wednesday or Thursday - and it would
continue the wet weather we have been in for the last week or so.

Temperatures through the long term will be quite stable with
afternoon highs in the low 90s and overnight lows in the mid to
upper 70s.

Fowler

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 236 AM CDT Wed Aug 24 2022

See short term for general fcst reasoning. Shra/tstm chances should
be on the high side for terminals CXO southward today. VFR
conditions will generally prevail outside of the stronger
cells/rainfall. Reduced visibilities and MVFR cigs in/near any
stronger cells.

47

&&

.MARINE...
Issued at 236 AM CDT Wed Aug 24 2022

Moderate onshore flow of around 10 knots with wave heights between
2 and 3 feet will persist through the weekend. The flow may
increase to near 15 knots during the overnight periods, so small
craft may need to exercise caution. Scattered showers and
thunderstorms will persist into next week with locally gusty winds
and higher seas will occur near stronger storms.

Fowler

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)	  92  75  93  75 /  40  20  30  20
Houston (IAH)			  89  76  91  75 /  70  40  60  40
Galveston (GLS)			  90  80  91  80 /  70  60  60  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&

SHORT TERM...47
LONG TERM....Fowler
AVIATION...47
MARINE...Fowler