152
FXUS64 KCRP 260153
AFDCRP

Area Forecast Discussion
National Weather Service Corpus Christi TX
853 PM CDT Wed Sep 25 2024

...New UPDATE...

.UPDATE...
Issued at 845 PM CDT Wed Sep 25 2024

Based on the latest dewpoint analysis, the cold front was located
along a line from near Cotulla to Cuero and drifting slowly
south. Moisture pooling ahead of this boundary (PWATs 1.9")
combined with marginal instability (CAPEs 1500-2000 j/kg) and
presence of an upper level trough axis draped overhead will
continue to enhance convection along the southern portions of our
county warning area for the next few hours. The latest model
guidance still supports the front reaching the coast around 06z
with drier air filtering in in its wake. Winds should pick up over
the gulf waters as the front moves off the coast with SCEC
conditions possible overnight, possibly reaching SCA conditions
Thursday morning. Current forecast is on track and no changes are
anticipated.

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 339 PM CDT Wed Sep 25 2024

Key Messages:

- Marginal risk of severe thunderstorms through this evening.

- High risk of rip currents Thursday into Thursday night.

- Increased risk of Coastal Flooding Thursday night into Friday.

Showers and thunderstorms are currently impacting portions of the
CWA this afternoon. The activity has been sparked ahead of a cold
front in response to a highly unstable airmass in place with
MUCAPE values at over 4000J/kg, very little CIN and enough
moisture (PWATs 1.75"). SPC has maintained the eastern third of
the CWA under a Marginal risk for severe weather through this
evening. The special 18Z sounding is indicating DCAPE values over
1300 J/kg, therefore, strong winds will be the primary hazard
with this activity in addition to some small hail.

The aforementioned cold front is progged to arrive later tonight
bringing much drier and cooler air into the region effectively
ending our rain chances. Winds will briefly pick-up behind the
boundary resulting in Small Craft Advisory conditions over
portions of the marine zones. Although temperatures will be a bit
slower to respond, minimum temps are forecast to be in the mid 60s
to mid 70s range tonight. Highs on Thursday will peak in the
upper 80s to low 90s, but minimums Thursday night will drop into
the 60s areawide. How nice for a change!

A High risk of rip currents remains in effect for Thursday along
the Gulf-facing beaches of the Middle Texas coast. This is as a
result of the arrival of longer swell periods in association to
Hurricane Helene in the eastern Gulf. After taking a look at
observations from both buoy 42019 and 42020, and noticing that
both are reporting swell periods of only 5 seconds at 1 ft, have
opted for not issuing a Coastal Flood Advisory just yet for
tonight`s high tide cycle. Last night`s tides made it to 1.9 ft
MSL and no flooding was registered. Tonight, tides are forecast to
be around 2.0 ft MSL, but swell periods over 10 seconds are not
progged to arrive until later in the day on Thursday. However,
have passed this information along to the evening shift so they
can keep track of any changes in coastal conditions. A Coastal
Flood Advisory will be much likely to occur on the Thursday night
high tide cycle. P-ETTS are indicating tides to reach 2.5 ft MSL
with 12-14 second swell periods.

&&

.LONG TERM...
(Friday through next Tuesday)
Issued at 339 PM CDT Wed Sep 25 2024

Key Messages:

- Increasing risk of rip currents and potential coastal flooding
  late this week as Hurricane Helene moves across the Gulf.

We open up the long term forecast with the remnants of Helene moving
across the southeast US and an upper level ridge building across the
southwest US. As Helene moves off to the east, the ridge will expand
across the Plains. Much drier air and increased subsidence will keep
us dry through the weekend. Moisture will begin to push back into
the area early next week which will lead to some low end rain
chances, mainly over our coastal waters.

Temperatures will be rather pleasant over the next several days.
Highs will settle into the low to mid 90s. Drier air will keep heat
indices in check with a minor heat risk through the period. Clear
skies and dry conditions will allow temps to drop into the 60s for
our inland areas.

We will be holding onto a few coastal/marine concerns as we head
into the weekend. Increased swells from Hurricane Helene will begin
to arrive over the next day and continue for a few days. Gerling-
Hanson plots suggest 12-14s swells along our coast which will be
more than enough to drive water up our Gulf-facing beaches. PETSS
guidance hints at tides approaching 2.5ft MSL during Friday`s high
tide cycle. In addition, the high risk of rip currents is likely to
be extended beyond Friday.

&&

.AVIATION...
(00Z TAFS)
Issued at 614 PM CDT Wed Sep 25 2024

Scattered thunderstorms will remain possible through mid-late
evening (around 03z) ahead of a cold front. Wind gusts up to 30
knots and brief heavy downpours could result in IFR conditions
in and near thunderstorms. Then north winds and drier air will
filter into the region overnight in the wake of the front with
clearing skies. Expect mostly clear skies and north winds 10-15
knots on Thursday.

&&

.MARINE...
Issued at 339 PM CDT Wed Sep 25 2024

A weak to moderate onshore flow this evening will become moderate
to strong offshore flow early Thursday morning in response to a
passing frontal boundary. A Small Craft Advisory is in effect
across the near and offshore waters north of Port Aransas on
Thursday. Waves are likely to become elevated offshore Thursday
afternoon, which may prompt the Advisory to be extended. Across
the southern waters and bays, winds will generally be at moderate
levels. Some thunderstorms will be possible ahead and along the
boundary this evening, with strong winds being the primary hazard.
As Helene moves across the Gulf, increased swells will lead to
hazardous marine conditions as we head into the weekend. Brief
periods of Small Craft Advisory conditions may develop at times.
Otherwise, dry conditions will continue over the weekend. Rain
chances gradually increase early next week as moisture begins to
return.

&&

.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi    71  90  68  91 /  30   0   0   0
Victoria          69  91  62  93 /  20   0   0   0
Laredo            71  91  67  94 /  20   0   0   0
Alice             70  91  64  93 /  20   0   0   0
Rockport          74  92  72  92 /  30   0   0   0
Cotulla           69  93  65  95 /  10   0   0   0
Kingsville        71  90  67  92 /  30   0   0   0
Navy Corpus       75  88  75  88 /  40   0   0   0

&&

.CRP WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk from 7 AM CDT Thursday through Friday
     morning for TXZ345-442-443-447.

GM...Small Craft Advisory from 7 AM to 4 PM CDT Thursday for GMZ255-
     275.

&&

$$

SHORT TERM...JM/75
LONG TERM....LS/77
AVIATION...JM/75