Timeline: Texas cold front brings hail, heavy rainfall risk to major cities

Another cold front sweeping across Texas at the tail end of this week should keep temperatures low. However, it also means a pretty gloomy weekend for much of the Lone Star State, including the risk for severe storms and heavy rainfall for some regions.

Severe storm risks are on the rise from Dallas down to San Antonio while areas west and south of these regions may see far less rain accumulation. Though, it’s still early days in the forecast, and surprise impacts have cropped up as severe weather season is in full swing.

According to the long-term forecast from the National Weather Service Amarillo office, a jet streak will likely hit the Texas Panhandle by Thursday. By that afternoon, as systems mix, sustained winds up to 30-40 mph and gusts up to 55 mph will likely sweep the area. For context, the National Weather Service says winds under 39 mph have very little chance of causing any damage, but winds over 39 mph can cause limited damage.

By Thursday night, a cold front will blow in. Afternoon temperatures will rapidly decline, dropping from 90 degrees Thursday, April 17, to 81 on Friday and a mere 69 degrees on Saturday. As temperatures dip, rain chances climb. There’s a 20% chance of showers Friday night, and those odds climb to 30% Saturday and 40% by Sunday.

By Monday, it should be clear skies and slightly warmer, at 81 degrees, again.

Making its way across Texas, the cold front should hit North Texas cities, like the greater DFW, by Friday night. This will drop highs in the area by nearly 10 degrees, but it also spells severe storm risks for the area that’s been hit hard early on in severe weather season.

“A faster track of the front or any other surface features may bring the potential for a few showers/storms as early as Friday afternoon, but at this time the chances are low (20%),” the NWS Dallas/Fort Worth office says. “Most of the long-range models are also showing plenty of instability and shear for some storms to become strong or severe. This threat will persist into the evening and overnight hours as better large-scale ascent moves over our area.”

Rain chances crop up Friday night at 50% and jump to 60% the following morning and afternoon. Saturday night, there’s a 70% chance of showers and thunderstorms, odds which drop to 60% the following day. Shower and thunderstorm odds continue through the weekend and into the start of the week.

“Given [the cold front’s] slow progress, widespread showers and storms are likely, particularly Saturday night into Sunday morning. Not only we will have to monitor the potential for strong/severe storms, but also the threat for locally heavy rain and training storms both Saturday and Sunday,” the Dallas office warns.

The National Weather Service Austin-San Antonio office says the cold front should dip down from North Texas into South Central Texas, including the greater San Antonio-Austin metro area, late Saturday. Though, a dryline sweeping the region Friday could spell a first round of severe storms.

“By late Friday, an upper-level low will begin sliding eastward into the Four Corners. This will set the stage for a sharpening dryline Friday afternoon and evening, along with increased chances for showers and thunderstorms, some of which could be severe,” the NWS says. “By late Saturday, a cold front will dive south out of north Texas into the region, bringing another chance at showers and storms to the region.”

The national weather forecaster says all that’s needed to make storms severe is moisture, instability and a source of lift. Apparently, all three ingredients are present on Friday and Saturday, creating a primary risk of large hail and damaging winds. Rain chances will peak on Saturday night, at 40%, and hover at least 20% from Friday night well into the start of next week.