textproduct: Corpus Christi

KEY MESSAGES

Issued at 612 AM CDT Sun Sep 27 2026

- Above-normal temperatures continue through early next week.

- Increase in rain chances starting midweek, with a potential for heavy rainfall in the latter half of the week.

- Minor coastal flooding possible starting early next week.

DISCUSSION

Issued at 1231 AM CDT Sun Sep 27 2026

The mid-level ridge that has been dominating our weather pattern will remain in place until early next week. Generally, it will continue to be hot and dry, although an isolated shower or thunderstorm promoted by the sea breeze cannot be ruled out. On the other hand, most locations will remain dry through Monday.

Attention then shifts to an approaching mid-level trough, associated front and its effects starting midweek next week. While some discrepancies remain, model guidance is beginning to come into agreement regarding timing and impacts towards South Texas. Overall, models suggest a mid-level low will approach Texas whilst interacting with the remnants of Hurricane Polo as it approaches West Texas. Initially, there was uncertainty about how much Polo would affect the mid-level low, but now, confidence has increased as recent guidance favors the mid-level low absorbing Polo's remnant moisture/circulation, rather than Polo substantially altering the low's track. Confidence is the exact evolution remains somewhat limited, however, and changes in the interaction could affect rainfall timing and amounts across South Texas.

As the front makes its way into Texas, model guidance suggests it will temporarily stall over West/Central Texas around midweek. As it stalls, the front will draw moisture from the Gulf, meaning increased PWAT values for South Texas, with values approaching 2.2- 2.4", according to the GFS, across the CWA. With the increased moisture and sufficient instability, rain chances will increase starting Tuesday eventually becoming more widespread as the week goes on. Additionally, the aforementioned PWAT values are supportive of heavy rainfall, which could lead to localized flooding. Confidence is not particularly high due to the lack of a lifting mechanism as the front stalls, but an outflow boundary from the northern storms making its way south could help with increased convection in addition to the seabreeze. Ultimately, we are still 5 days out from the expected impacts and model guidance could still change, but overall, chances for rain will increase significantly starting midweek.

Through early next week, temperatures will stay above normal. Increasing cloud cover in addition to increased convection from the aforementioned front in the latter half of the week will help keep temperatures down, but it will still be warm and humid. Afternoon highs will drop from around the mid to upper 90's to levels closer to 90 and the mid 80's. A moderate to major heat risk persists through Wednesday, becoming minor by the end of the week as the increased cloud coverage and convection make their way into the area.

Regarding minor coastal flooding, the P-ETSS estimates tide levels up to 1.8 feet above MSL beginning Tuesday during high tide. There seems to be an upward trend through midweek regarding the levels, but we will monitor the trend to see if it continues and may issue products as necessary.

AVIATION

(12Z TAFS) Issued at 612 AM CDT Sun Sep 27 2026

Despite MVFR conditions at ALI for the next few hours, VFR conditions are expected throughout this TAF cycle with light winds.

MARINE

Issued at 1231 AM CDT Sun Sep 27 2026

A gentle to moderate east to southeasterly flow will continue Saturday through the first half of next week, with generally low seas. Winds and seas are expected to increase during the latter half of next week as the pressure gradient tightens in response to an approaching cold front. Small Craft Advisory conditions may become possible during this time, with seas building to around 4-7 feet. Rain chances will remain low through Monday before increasing over the waters Tuesday. Shower and thunderstorm chances are then expected to slowly increase Wednesday with moderate rain chances continuing through the end of the period. Locally higher winds and seas will be possible in and around thunderstorms.

FIRE WEATHER

Issued at 1231 AM CDT Sun Sep 27 2026

No significant fire weather concerns are anticipated through the period. Minimum RH values will generally remain above 30% across the western portions of South Texas, while east to southeast winds 10-15 mph may increase to 20-25 mph around mid-week in response to an approaching disturbance. However, the low RH values and increased winds do not appear to coincide, and therefore no significant fire weather risk is expected at this time.

PRELIMINARY POINT TEMPS/POPS

Corpus Christi 95 77 93 77 / 0 10 10 10 Victoria 100 72 98 73 / 0 0 10 0 Laredo 102 77 101 77 / 0 0 0 0 Alice 99 74 98 74 / 0 0 0 0 Rockport 92 79 91 80 / 0 0 10 10 Cotulla 101 76 100 75 / 0 0 0 0 Kingsville 98 74 96 76 / 0 10 0 10 Navy Corpus 90 81 89 81 / 0 0 10 20

CRP WATCHES/WARNINGS/ADVISORIES

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