Tropical wave brings rain to South Texas this week. Here’s what chances look like for San Antonio

The National Hurricane Center is still highlighting the Western Gulf of Mexico for potential tropical development early this week as a tropical wave approaches South Texas.

This disturbance will bring rain to parts of the Lone Star State, but the heaviest rain still looks to stay south of San Antonio.

Key Points

• A tropical wave will move into the Western Gulf on Monday, Aug. 21, bringing tropical moisture to parts of South Texas.

• The National Hurricane Center has highlighted the Western Gulf with a medium (60%) chance for tropical development during this timeframe.

• Regardless of development, tropical moisture is expected to filter into parts of South Texas by Tuesday, Aug. 22, but the more widespread, heavy rainfall will stay south of San Antonio.

• Not all of South Central Texas will find rain early this week, but isolated-to-widely scattered rain will be possible, with better chances the farther south you go.

Here’s a breakdown of what to expect in the week ahead:

Monday (8/21)

• Still a hot and mainly dry day across South Central Texas with more high temperatures in the triple digits.

• Fire danger will also be elevated, so please continue to practice fire safety!

• A stray shower or two (~10%) can’t be ruled out later in the day, but coverage is expected to be low.

Tuesday (8/22)

• Rain and tropical moisture will start to work into South Texas early Tuesday morning.

• The far northern extent of this rain could send isolated-to-widely scattered downpours through the San Antonio area by late morning and into the early afternoon, but the higher coverage and heavier rainfall will stay to our south.

• It’s important to note that not everyone in South Central Texas will tap into the rain unfortunately, but chances will increase the farther south you go.

• Added cloud cover and passing downpours are expected to hold temperatures down slightly, with forecast highs in the 90s for the first time this month!

• Expect a healthy east wind to pick up throughout the day, with wind gusts upwards of 30 – 35 mph at times.

Wednesday (8/23)

• A stray, lingering shower or two can’t be ruled out on Wednesday, but coverage will be MUCH lower as this low-pressure system departs to the west.

• Expect warmer temperatures compared to Tuesday, with a forecast high near 100° in San Antonio.

Late this week (8/24 – 8/25)

• Rain chances come down and temperatures crank back up as high pressure builds back over Texas.

• Triple digits return by Thursday and continue on into next weekend, with just stray chances (10% – 20%) for a quick shower.

What about tropical development?

As of Sunday, Aug. 20, the National Hurricane Center continues to place a medium (60%) chance for tropical development in the Western Gulf of Mexico over the next 48 hours.

Regardless of tropical development, the current trends suggest that the heavier, more beneficial rain will stay south of San Antonio, closer to the Rio Grande Valley.

With that in mind, know that this pattern change won’t be a drought-busting rain event, especially for those in the Hill Country that need it the most.

ELSEWHERE IN THE ATLANTIC

Less than a month out from the official peak of the Atlantic hurricane season on Sept. 10, the tropical Atlantic has come alive, with multiple areas now being monitored by the National Hurricane Center:

The disturbances have varying chances for tropical development over the next seven days, but we’ll keep eyes on it.

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