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Tropical Storm Harold rolled across the midpoint of Padre Island, Texas, at 11 a.m. EDT Tuesday morning, making landfall less than 12 hours after it was named. Harold arrived in the sparsely populated area with top sustained winds of 50 mph and a shield of heavy rain, mainly near and to the north of its center.

Harold failed to organize until late in its trek across the Gulf of Mexico. It became Tropical Depression 9 at 5 p.m. EDT Monday and Tropical Storm Harold at 11 p.m., then intensified a bit more just before landfall. Given another couple of days over the extremely warm waters of the Gulf of Mexico, Harold could have been a much more fearsome storm.

With so little time to organize, Harold delivered only a modest storm surge. The highest surge totals occurred well north of Harold’s landfall location, including 2.2 feet at San Luis Pass, 1.6 feet at Port Lavaca, and 1.8 feet at Galveston Bay. About 40 miles north of Harold’s center, Corpus Christi International Airport recorded sustained winds of 36 mph gusting to 59 mph at 12:51 p.m. EDT. The airport received 3.06 inches of rain through 2 p.m. EDT Tuesday, and the National Hurricane Center was predicting widespread 3- to 5-inch totals across South Texas, with localized totals up to 7 inches. A few tornadoes could develop in the strongest rainbands over South Texas on Tuesday afternoon.

Harold is expected to dump even heavier rains later on Tuesday as it crosses from the tabletop-flat landscape of South Texas and pushes easterly winds against the rugged terrain of northeast Mexico, raising the potential for flash flooding and mudslides. The rains in the United States should be largely beneficial, as all of South Texas is in moderate to severe drought, with pockets of extreme drought along the middle Texas coast.

The name Harold is being used for the first time this year as a replacement for Harvey, which stuck the Texas coast just north of Corpus Christi on August 25, 2017. Harvey was the first major hurricane to make a landfall on the U.S. Gulf or Atlantic coast in almost 12 years. In contrast, the past six years have produced (including Harvey) seven major U.S. Gulf or Atlantic landfalls, plus Maria in Puerto Rico, with a mind-boggling inflation-adjusted damage total (2023 USD) of more than $587 billion.

Figure 1. Satellite image of Tropical Storm Franklin (center) in the eastern Caribbean at 1:50 p.m. EDT Tuesday, August 22, 2023. (Image credit: RAMMB/CIRA/CSU)

Franklin to dump heavy rains on Hispaniola and Puerto Rico

Although it was struggling to fully organize on Tuesday in the eastern Caribbean, Tropical Storm Franklin will still be a serious rainmaker, and potentially a major floodmaker, as it moves through the Greater Antilles from late Tuesday into Wednesday. As of 2 p.m. Tuesday, the poorly defined center of Franklin was placed by the National Hurricane Center (NHC) at about 230 miles south-southwest of Santo Domingo, Dominican Republic. Squalls were already pushing northward into Hispaniola and Puerto Rico on Tuesday afternoon.

Showers and thunderstorms (convection) around Franklin were divided into a sprawling main cluster, east of the center, and a smaller burst near and just west of the center, where it appears that Franklin’s main circulation may be shifting. A NOAA Hurricane Hunter flight was investigating Franklin on Tuesday afternoon. Regardless of the center’s location, heavy rains will be moving north with Franklin into Hispaniola, including Haiti and the Dominican Republic, with lesser rains across Puerto Rico. Exactly where the heaviest rains set up will depend largely on how Franklin’s attempts to reorganize evolve on Tuesday afternoon and evening.

Despite its passage over very warm waters (sea surface temperatures around 29 degrees Celsius or 84 degrees Fahrenheit), with ample deep oceanic heat content, Franklin will continue to be plagued with strong westerly wind shear of 15-20 knots pushing its convection eastward. Since Franklin will have little time to spin up a more potent circulation before its expected landfall on Wednesday morning along the south coast of the Dominican Republic, winds will likely remain below hurricane force, but widespread gale-force winds can be expected over Hispaniola, enough to bring down trees and power lines in saturated soil. Mudslides and flash floods are also a distinct threat, especially in and near the higher terrain of Haiti and the Dominican Republic, where rainfall totals of 5 to 10 inches could spike to 15 inches or more locally. Squally rainbands may persist in some locations on Wednesday well after Franklin moves north away from the islands.

Figure 2. Track forecasts out to 10 days for Franklin from the 0Z Tuesday, August 22, run of the European ensemble model (left) and the 12Z Tuesday run of the GFS ensemble model (right). Individual forecasts of the 51 Euro and 31 GFS ensemble members are the lines color-coded by the wind speed in knots they predict for Franklin; red colors correspond to a Category 1 hurricane. The time in hours from the model initialization time is in gray text. (Image credit: weathernerds.org)

Uncertainty over Franklin’s future extends to the long-range too. Once well north of Hispaniola, Franklin will still face hostile wind shear, but the shear is predicted to relent somewhat by next weekend when Franklin will be traversing unusually warm subtropical waters of 29-30°C (86-88°F). The NHC is predicting Franklin to attain hurricane strength by Sunday, when steering currents may be angling Franklin toward the north-northwest. Bermuda will need to monitor the potential threat from Franklin early next week.

Elsewhere in the Atlantic

Tropical Storm Gert was declared post-tropical at 11 a.m. EDT Tuesday after tenaciously clinging to life east of the Lesser Antilles for almost three days, considerably longer than expected. In the remote central Atlantic, the remnants of Tropical Storm Emily could briefly reorganize late this week over unusually warm subtropical waters. In its Tropical Weather Outlook issued at 2 p.m. EDT Tuesday, NHC gave the remnants of Emily a 10 percent chance of redevelopment in the next two days and a 40 percent chance in the next seven days.

A disturbance in the eastern tropical Atlantic designated as Invest 92L could develop late this week as well. NHC gives 92L a 10 percent chance of becoming at least a tropical depression in the next two days and a 30 percent chance by next Tuesday. Both 92L and any redevelopment from Emily’s remnants are expected to track far east of the Americas, staying over the open Atlantic.

A frenzied pace in the Atlantic

As noted by meteorologist Phil Klotzbach (see embedded post below), the burst of four named storms developing in a span of just 39 hours from Sunday into Tuesday was unprecedented in 172 years of Atlantic recordkeeping, keeping in mind that some weak storms were likely missed in the pre-satellite era. Even though Emily, Franklin, Gert, and Harold all formed in short order, none of these systems made it close to hurricane strength; at this point, only Harold has a chance to do so.

When El Niño conditions are intensifying, as they are right now, hurricane production is typically blunted in the Atlantic, especially over the Gulf of Mexico and the Caribbean. This year, forecasters anticipated a “clash of titans” between the potent El Niño event taking shape and the record-warm waters over most of the tropical and subtropical Atlantic. The most recent batch of seasonal forecasts, as compiled by Colorado State University and the Barcelona Supercomputing Center, vary from above to near to slightly below average.

For now, it seems that the scorching sea surface temperatures have been enough to push several marginal systems up to tropical-storm strength, despite the dry air and wind shear aloft that’s common during El Niño years.

As always, it only takes a brief window of more favorable atmospheric conditions to get a dangerous hurricane, even during El Niño. The infamous poster child for this is 1992: that year’s first named storm – Hurricane Andrew – did not develop until late August, but it intensified rapidly and ripped into South Florida as a catastrophic Category 5 storm.

Hilary gives Death Valley its wettest day on record

Widespread rains from Tropical Storm Hilary drenched the normally bone-dry Death Valley, California, area in what appears to have been the wettest day on record for most if not all of the valley. The calendar-day totals on Monday, August 21, were comparable to an average year’s worth of rain. Calendar-day totals for Monday, and 24-hour totals from 3 a.m. PDT Monday to 3 a.m. PDT Tuesday where available, as compiled by weather historian Christopher Burt, included:

  • Stovepipe Wells:  2.89”; peak 24-hour total 3.01”
  • Furnace Creek: 2.20 (all-time calendar-day record)
  • Badwater:  2.17”; peak 24-hour total 2.29
  • Saratoga Spring: 2.40” (through 11:34 p.m.); peak 24-hour total 2.51”

Astoundingly, it was just last year that Furnace Creek had set its all-time calendar day and 24-hour precipitation record with 1.70 inches on August 5, 2022. “That event did not encompass the entire valley as the current event has,” notes Burt. Moreover, it was produced by thunderstorms within a strong monsoon flow without a landfalling tropical cyclone. Only a few other days in 112 years of recordkeeping at Furnace Creek have produced an inch or more of rain; prior to last year, the record was 1.47″ from April 15, 1988.

Jeff Masters contributed to this post. Website visitors can comment on “Eye on the Storm” posts (see comments policy below). Sign up to receive notices of new postings here.

Bob Henson is a meteorologist and journalist based in Boulder, Colorado. He has written on weather and climate for the National Center for Atmospheric Research, Weather Underground, and many freelance...