Jeff Masters Weather Blog

Beryl regains steam en route to Texas coast » Yale Climate Connections

After racking up more accumulated cyclone energy (ACE) than any Atlantic hurricane so early in the season – not to mention hitting category 5 strength at a record-early point – Tropical Storm Beryl was hurtling toward its final landfall. One last round of strengthening is expected before Beryl reaches the middle Texas coast early Monday morning, and Beryl could make landfall as a rapidly intensifying category 1 or 2 hurricane.

At 11 a.m. EDT Sunday, Beryl was a strengthening tropical storm with top winds of 65 mph, located close to 200 miles offshore from both Corpus Christi and Matagorda Bay. Beryl was moving northwest at 10 mph.

Forecast for Beryl

The easier part of today’s Beryl forecast is the track. Now being tugged northward by a broad upper trough over the central United States, Beryl will continue angling northwest and then northward. Track models are in firm agreement that Beryl will reach the coast early Monday somewhere between Corpus Christi and Houston, perhaps just east of Matagorda Bay, and track northward from there across eastern Texas on Monday. Such a track would put the greatest storm surge toward Beryl’s eastern flank, including near the Freeport area (see below), with disruptive and damaging winds possibly affecting the Houston area. Even as it weakens rapidly, Beryl will still be dumping heavy rains along and near its track.

The tougher part of the forecast is gauging just how strong Beryl will get before it reaches the Texas coast. Passage over the Yucatán Peninsula dented Beryl’s strength substantially, and then the storm gulped huge volumes of dry air on Saturday over the western Gulf. As of Sunday, Beryl still had a robust circulation around which to refashion itself, but its inner core was seriously disrupted, and it will take time for Beryl to rebuild its eye and eyewall. As a result, the most likely period for any rapid intensification will be toward the latter part of the 12 or so hours from Sunday afternoon up through landfall in the predawn hours on Monday. The 12Z Sunday run of the SHIPS model gave a 28 percent chance that Beryl’s top winds would strengthen to 85 knots (100 mph), near the midpoint of the category 2 range. The Sunday-morning (6Z) runs of NOAA’s four main high-resolution hurricane models were evenly split between category 1 and category 2 landfalls.

Beryl will have supportive conditions for strengthening right up to landfall. Wind shear will be light to moderate (less than 10 knots) and the upper-level southwest winds associated with the central U.S. trough could actually help ventilate the storm. Moreover, Beryl will be passing over very warm waters for early July, with sea surface temperatures of 29-30 degrees Celsius (84-86 degrees Fahrenheit). The remaining challenge for Beryl would be to wall off a moist core that can fend off the dry air that remains extensive over the western Gulf.

The Gulf of Mexico is notorious for breeding hurricanes that rapidly strengthen as they approach the coast, and researchers are finding that such events are becoming more common with Atlantic hurricanes as a result of human-produced climate change. We should not be surprised if Beryl makes landfall as a rapidly intensifying category 1 or 2 storm.

Flood threat from Beryl

A band of heavy thunderstorms was already dumping rain on the upper Texas coast, including the Houston area, at midday Sunday on the outer fringes of Beryl. Torrential rains, perhaps a foot or more locally, will spread into central Texas late Sunday into Monday, with a strip of 8-12 inches expected in a swath near the coast (Fig. 1), with localized totals of 15 inches. Heavy rains of 4-6 inches could occur along Beryl’s track all the way to St. Louis, Missouri. Unfortunately, the heaviest rains will miss the drought-parched areas of southwest Texas, and will impact areas with wet soils prone to flooding.

Figure 1. Rainfall forecast for Beryl issued on Sunday morning, July 7, 2024. (Image credit: NHC)

On Sunday, the Trinity River Authority stated on its website that initial repairs on Lake Livingston Dam would be completed by Monday afternoon, July 8. Lake Livingston is a reservoir about 90 miles north-northeast of Houston that provides the majority of the city’s water. The surrounding watershed is predicted to receive 4-6 inches of rain from Beryl (Fig. 1). Lake Livingston Dam was placed under a “potential failure watch” by the Trinity River Authority on June 28 following weeks of heavy rain. The agency has maintained there is no immediate danger of a failure or breach.

Wind, tornado, and riptide risk

As usual with landfalls, the most damaging winds from Beryl will occur along the coast near and to the right of where the eye crosses the coast. Beryl will not be an especially large hurricane, and its predicted angle of approach to the curved coastline means that the area of strongest winds to the right of the center would remain largely offshore until after landfall.

Even though it is some distance from the landfall location, the Houston area should prepare for widespread sustained winds of 40 to 60 mph, plus higher gusts, that could bring down tree limbs and power lines. As shown in Figure 2 below, there is a 60 to 80 percent chance of winds in the tropical-storm range in the Houston-Galveston area, and power outages may be widespread.

Figure 2. Probabilities of tropical-storm-force winds with Beryl as of 7 a.m. CDT July 7, 2024. Image credit: NHC.

In its one- and two-day severe-weather outlooks issued Sunday morning, NOAA’s Storm Prediction Center called for a Slight Risk of tornadoes (level two out of five on their five-tiered risk scale) on both Sunday and Monday. The main risk would be to the right of where the center makes landfall, where the wind shear supportive of rotating storms and tornadoes will be maximized.

High surf and rip currents can be expected well north of Beryl along the western U.S. Gulf Coast on Sunday.

Beryl’s storm surge

Since Beryl is a fairly compact tropical storm with less than a day until landfall, it will not be able to pile up a huge storm surge. NHC is calling for a peak surge of 4-6 feet near and to the right of where the eye crosses the coast. While a surge of this magnitude will cause moderate coastal flooding, beach erosion, and some damage, it will be a far cry from the devastating 17-foot storm surge that category 2 Hurricane Ike of 2008 brought to the coast northeast of Galveston.

Low tide along the central Texas coast is between 3-4 a.m. CDT Monday, and high tide is between 3-4 p.m. However, since tidal range between low tide and high tide is only about 0.5 feet, the timing of Beryl’s arrival with respect to high tide will be relatively unimportant. NOAA’s Tides and Currents website showed that water levels at Freeport, located about 55 miles south of Houston, were running about 2 feet above normal at 2 p.m. EDT Sunday. Freeport, which has records extending back to 1954, experienced its highest water level of 4.95 feet above mean higher high water (MHHW) on July 15, 2003 during the landfall of category 1 Hurricane Claudette. A storm surge of 4-6 feet is predicted at Freeport, so their all-time (70-year) record may be in jeopardy. Water levels higher than 4 feet above MHHW are classified as “Major” flooding, the highest class of coastal flooding defined by NOAA.

For more coverage of Beryl, we recommend The Eyewall, written by Texas-based editors Matt Lanza and Eric Berger.

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