textproduct: Corpus Christi

KEY MESSAGES

Issued at 134 PM CDT Sun Sep 27 2026

- Temperatures will remain above normal through the first half of the week.

- Increasing rain chances by mid-week with heavy rainfall and localized flooding possible the latter part of next week.

- Minor coastal flooding possible starting early next week.

DISCUSSION

Issued at 134 PM CDT Sun Sep 27 2026

Heat remains a concern through the first half of the week with above normal temperatures continuing under a persistent ridge of high pressure. The high pressure will also inhibit convective development, although a rogue shower or thunderstorm along the sea breeze, can not be ruled out. Most locations will remain dry.

It is looking like we will see some relief from the heat and lack of rain beginning mid-week. The ridge is forecast to shift east as a mid/upper level long wave trough digs across the western U.S. Sufficient moisture combined with embedded short waves ahead of the main long wave trough, will be conducive for convective development beginning Tuesday with a 20-35% chance across the eastern CWA.

Models indicate that the long wave trough will deepen and become cut off as it approaches West Texas. This will strengthen the low level winds across S TX and usher deeper moisture across the area from the gulf in the low and mid levels. The cut-off low will also tap into mid/upper level moisture from the remnants of Hurricane Polo in the Pacific.

A cold front associated with the mid/upper low is progged to move into N TX on Wednesday while a pre-frontal surface trough develops across S TX. This surface trough will provide low level moisture convergence and increase rain chances to 30-50% across the Victoria Crossroads on Wednesday. Models indicate widespread showers and thunderstorms by Thursday as the upper level moisture from the Pacific arrives and PWATs increase to 2.2-2.5 inches. This is almost 2 standard deviations above normal and is conducive for heavy rainfall with localized flooding possible. This moisture will interact with the pre-frontal surface trough and/or outflow boundaries from the convection expected across the Hill Country. The main cold front is now forecast to move into S TX Friday or Saturday with winds strengthening from the north and cooler temperatures for the weekend. Medium rain chances continue through the weekend as the upper low slowly tracks east across TX.

Confidence is medium with respect to increasing rain due to the upper low and abundant moisture. However, confidence with respect to the cold front remains low as models have been differing from run to run on timing and just how far south the front goes before stalling.

As for minor coastal flooding, the P-ETSS indicates tide levels up to 1.8 feet above MSL for Tue-Wed during times of high tide. There is low confidence that water will reach the dunes due to light onshore winds through Tuesday, then 15-25 knots from the south mid- week, swell periods of 7 seconds or less, and the moon phase will be approaching the 3rd quarter. None of which are favorable for tidal overflow. Will continue to monitor trends for any changes.

AVIATION

(18Z TAFS) Issued at 134 PM CDT Sun Sep 27 2026

VFR conditions are expected to prevail through the TAF cycle. However, brief MVFR VSBY and/or CIGs will be possible after 09Z through mid morning Monday at the ALI TAF site. MVFR conditions are also possible at VCT, but the probability is too low to mention in the TAF at this time. Winds will remain light, with a mainly east to southeast direction.

MARINE

Issued at 134 PM CDT Sun Sep 27 2026

A gentle to moderate (BF 3-4) east to southeasterly flow is expected to persist, along with seas between 2-3 feet, through Tuesday morning. Winds are forecast to increase to fresh to strong (BF 5-6) by mid-week as low pressure deepens over West Texas and a cold front approaches the Hill Country. Small Craft Advisories may be needed by Tuesday night. Low rain chances expected through Tuesday, then increase to a medium to high chance Wednesday through the weekend.

PRELIMINARY POINT TEMPS/POPS

Corpus Christi 77 93 78 93 / 0 10 30 30 Victoria 73 98 73 97 / 0 30 20 30 Laredo 77 101 77 101 / 0 0 0 0 Alice 74 98 75 97 / 0 0 10 20 Rockport 79 92 79 91 / 0 20 20 30 Cotulla 76 100 76 99 / 0 0 0 0 Kingsville 75 96 76 95 / 0 0 20 30 Navy Corpus 81 90 81 89 / 10 10 30 30

CRP WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.