Area Forecast Discussion

KEY MESSAGES

Issued at 1205 AM CDT Tue Sep 15 2026

- Major to Extreme risk of heat-related impacts across a large portion of South Texas today, then lowering to a moderate to major risk the rest of the week.

- Very low rain chances today, then increasing to a medium to high chance by Thursday.

- Elevated Fire Weather conditions expected today. A Fire Danger Statement has been issued. Elevated Fire Weather conditions remain possible through Wednesday, mainly across the Brush Country and Rio Grande Plains.

DISCUSSION

Issued at 1205 AM CDT Tue Sep 15 2026

The heat continues to be a concern, but heat indices are expected to be generally less than 110 today. This is due to drier conditions with slightly lower dewpoints/RH values. A few locations may exceed 110 briefly. We may reach Heat Advisory criteria Wednesday, but it will be borderline. Heat Advisory conditions are less likely through the remainder of the week and into the weekend due to increasing rain chances/cooler temperatures. This will lead to the major to extreme risk of heat related impacts today to lower to a moderate to major risk the rest of the week.

Slightly drier conditions in the mid levels and PWATs generally less than 2 inches today will keep rain chances low to very low across most of S TX. Although a rogue shower along the sea breeze can not be ruled out.

Models have consistently shown a surge of deeper moisture advecting across S TX beginning Wednesday with increasing rain chances through Thursday. PWATs are progged to increase to as much as 2.4 inches, which will be conducive for locally heavy rain creating localized flooding problems, especially if the storms are slow moving. Highest rain chances Thursday are expected across the eastern half of S TX with PoPs from 35-60% and <35% closer to the Rio Grande.

Rain chances begin to drop off Friday to a 20-35% chance then 5-20% over the weekend as mid level ridging takes hold. Sufficient moisture should remain in place early next week for a 10-20% chance of showers and storms along the daily sea breeze.

Models show a long easterly fetch developing across the northern gulf waters this week which may help push water farther up the beaches. Will continue to monitor trends for slightly higher than normal tides and/or an increased rip current risk. At this time, minor coastal flooding is not anticipated but will continue to be monitored.

AVIATION

(06Z TAFS) Issued at 1205 AM CDT Tue Sep 15 2026

VFR conditions currently prevail across all terminals over South Texas, however we're already seeing streaks of MVFR ceilings over the inland Coastal Plains to Brush Country, near ALI. We'll carry TEMPOs for each site for occasional MVFR ceilings. Lighter winds over VCT may induce MVFR vsby as well. VFR conditions prevail by 15Z with southeasterly winds increasing to 15-20 knots with gusts around 25 knots midday through the afternoon hours.

MARINE

Issued at 1205 AM CDT Tue Sep 15 2026

A fresh (BF 5) breeze is expected south of Port Aransas across Corpus Christi and Baffin Bays and out to 20 nautical miles once again this afternoon. Small Craft Should Exercise Caution in the bays and nearshore waters south of Port Aransas through this evening. Otherwise, a gentle to moderate (BF 3-4) onshore flow is expected through the week and into the weekend. Very low rain chances expected today. Rain chances increase to medium on Wednesday and high chances by Thursday. Rain chances begin to decrease Friday with low to very low rain chances this weekend.

FIRE WEATHER

Issued at 1205 AM CDT Tue Sep 15 2026

Minimum relative humidity is expected to be around 20-30% this afternoon across the Brush Country. Thus, Elevated Fire Weather concerns are expected and a Fire Danger Statement has been issued for the Brush Country this afternoon. The ERC remains at the 75-90% percentile, and Elevated Fire Weather conditions will be possible at times through the period. The chance of wetting rains will be very low today, then increasing rain chances expected beginning Wednesday with the highest chance expected Thursday.

PRELIMINARY POINT TEMPS/POPS

CRP WATCHES / WARNINGS / ADVISORIES

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