Texans usually keep their eyes on the Gulf of Mexico during hurricane season.
However, residents may need to turn their heads toward the Pacific as remnants of Hurricane Pamela, which was circulating off the coast of the Mexican states of Jalisco, Colima and Michoacan on Tuesday, could cause havoc across portions of South Central Texas Wednesday and Thursday.
Pamela became the 16th named storm of the 2021 East Pacific hurricane season when it developed south of Mexico on Sunday evening. By Tuesday morning, Pamela had became the seventh East Pacific hurricane of the season.
National Weather Service forecasters expect what is left of Pamela after it makes landfall on the western coast of Mexico to be absorbed into an upper-level storm system across South Central Texas Wednesday and Thursday and combine with Gulf moisture to bring a high chance of showers and storms.
Jason Runyen, a meteorologist with the National Weather Service office in New Braunfels, said flash flooding is possible in Comal County starting Wednesday evening and into Thursday.
“The main threat with this system is going to be heavy rainfall and a potential that we could see some flash flooding in the area,” Runyen said. “Right now, we’re forecasting anywhere from 2 to 4 inches of rainfall across Comal County. There is a potential there could be some isolated pockets of higher amounts, although right now, that’s looking like it might set up farther west of Comal County. Two to four inches of rain could still cause some flooding in the area Wednesday night into Thursday morning.”
The greatest threat for excessive rainfall is forecast to be west of I-35 across the Hill Country, southern Edwards Plateau and the Rio Grande.
Some areas of South Central Texas could see two to five inches of rain with isolated higher totals of five to seven inches possible Wednesday and Thursday.
Forecasters stress, however, that the forecast remains fluid and adjustments are still possible on where higher rainfall amounts could occur.
A Flash Flood Watch went into effect late Tuesday across parts of the Edwards Plateau and Rio Grande Plains. The watch expands Wednesday morning to include the Hill Country and I-35 corridor, including New Braunfels and Comal County.
In addition, there is a very low but nonzero risk for a tornado or perhaps some damaging winds late Wednesday afternoon through the evening, mainly over the western half of the region.
Motorists traveling through the area could encounter very low visibility in heavy rainfall and submerged roadways due to low-lying and poor drainage flooding.
“Most of our flash flood fatalities come from people in vehicles,” Runyen said. “If you come across a flooded roadway, we always encourage people to turn around, don’t drown.”
Runyen added that heavy rainfall could come during the evening hours, making it more difficult to judge how much water is over the road.
A cold front looks to move through the region on Friday, bringing cooler temperatures and dry conditions for the weekend.
Pamela intensified into a hurricane early Tuesday morning and was forecast to become a Category 2 hurricane by early Wednesday.
“The combination of warm ocean waters and light wind shear will allow Pamela to intensify over the next couple of days,” AccuWeather Senior Meteorologist Rob Miller said Tuesday.
As Pamela tracks inland, a rapid loss of wind intensity is expected as the storm moves over higher terrain. This will cause Pamela to transition to a tropical rainstorm by Thursday, according to AccuWeather.