Thunderstorms in the forecast

HARLINGEN – The thunderstorms that chugged across the Valley for several hours Sunday left wildly divergent rainfall totals depending on location.

At Valley International Airport in Harlingen, the official rain gauge reading was 1.29 inches.

But areas to the west received much more, said Mike Castillo, senior meteorologist with the National Weather Service in Brownsville.

About 5 miles southwest of Harlingen, an unofficial volunteer weather observer recorded 4.06 inches of rainfall Sunday. And about a half-mile north of the city, another volunteer recorded 2.45 inches.

Most of the rain and severe weather was up the Valley from the Gulf of Mexico.

McAllen Miller International Airport reported 2.91 inches of rain, a record for the date. The previous rainfall record for the day was 1.95 inches set in 1970.

A rare tornado warning was issued for Hidalgo County on Sunday but there was no official confirmation of a funnel cloud. Castillo said there was one unconfirmed report of a tornado in the Hargill area, although “we did have quite a bit of wind damage reports.”

Castillo said tornado warnings were very rare in the Valley.

“We don’t get the classic-type tornadic thunderstom like North Texas, Oklahoma or the Central Plains,” he said. “Not that it can’t happen but they’re very small and very short-lived.”

Those that do occur are mostly byproducts of hurricanes or tropical storms, he said.

More rain is expected this week, as atmospheric conditions are expected to continue to be unstable.

“The next couple of days kind of hinges on a couple of things,” Castillo said. “There’s a large upper-level trough over the western U.S. and it’s going to be sending us some upper-level disturbances over the week.

“There’s also a weak cold front trying to take itself southward across Central Texas this week,” he added. “Typically this time of year it’s hard for us to get any kind of cold front in the Valley. They usually stall up toward Corpus Christi and the Houston area.

“That’s how we get those heavy rainfalls,” he concluded.

RAIN THIS WEEK

Tuesday: 20 percent chance thunderstorms, some severe

Wednesday: 30 percent chance thunderstorms

Thursday: 50 percent chance thunderstorms

Friday: 40 percent chance thunderstorms

Saturday: 30 percent chance thunderstorms

— National Weather Service

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