This story was last updated Monday evening. For Tuesday’s updates on Laura, see: Laura intensifying in Gulf of Mexico, threatens major hurricane strike in Texas and Louisiana

After raking the Dominican Republic, Haiti and Cuba, Tropical Storm Laura entered the Gulf of Mexico late Monday evening where it is poised to strengthen to a hurricane by Tuesday and then pose a serious threat to the coasts of Louisiana and Texas by midweek.

Computer models suggest that Laura could tap the exceptionally warm waters of the Gulf of Mexico and intensify into a large and dangerous hurricane.

Laura is forecast to make landfall late Wednesday or early Thursday as Category 2 or 3 storm with winds of 110 mph in the zone from near Galveston, Tex., to just west of Morgan City, La., where hurricane watches have been posted. Houston is under a tropical storm watch.

The National Hurricane Center is forecasting a “life-threatening” rise in water above normally dry land at the coast that could cause 7 to 11 feet of inundation. It issued storm surge watches from just southwest of Houston to coastal Mississippi. In addition, the storm is forecast to unload 4 to 8 inches of rain when it comes ashore and up to a foot in some areas, causing flash flooding.

While producing some areas of heavy rain along the northern Gulf Coast, the prior storm of concern, Marco, fell apart Monday due to wind shear. It was downgraded to a tropical depression late in the evening after making landfall as a minimal tropical storm at the mouth of the Mississippi River in southeast Louisiana.

The latest developments
  • For Laura, hurricane watches are in effect for Port Bolivar, Tex., to west of Morgan City, La., while tropical storm warnings cover the western third of Cuba, and parts of the Florida Keys. Storm surge watches span from San Luis Pass, Tex., to Ocean Springs, Miss., including Lake Pontchartrain.
  • For Marco, all tropical storm and storm surge warnings were discontinued, although its remnants may dump 1 to 3 inches of additional rain across the north-central Gulf Coast and Southeast through Wednesday.
August 24, 2020 at 11:11 PM EDT
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Key takeaways from Hurricane Center’s latest discussion: Keep a close eye on this storm, Houston

By Andrew Freedman

The National Hurricane Center’s 11 p.m. forecast package contains some key insights for anyone with interests along the Gulf Coast. Here are some of the themes that came across in the technical discussion, which is aimed more at an audience of other meteorologists (such as TV weather broadcasters) than the public.

  • Laura failed to weaken over Cuba. In fact, it has been intensifying and is about to have two full days over the warm waters of the Gulf of Mexico, which are running 1 to 2 degrees Celsius above average for this time of year. This means the storm is poised for potentially significant intensification.
  • The forecast wind speed at landfall has increased from previous forecasts, from 105 miles per hour to 110 mph. This is important because at this time range, the typical forecast intensity error is 15 mph. A “major” hurricane of Category 3 intensity or higher has winds above 111 mph, so it becomes clear that the storm could come ashore as a major hurricane.
  • The latest computer model runs of the European model in particular have caused a nudge west in the track forecast. If this trend continues, the NHC says, “Additional hurricane watches may be needed farther south along the Texas coast if the track forecast shifts toward the south and west tonight and Tuesday.” The implications of such a shift are significant, since the NHC has placed Houston in a tropical storm watch rather than a hurricane watch, and forecasters so far are favoring a hurricane landfall to the north of there. The latest discussion shows that is not a sure bet.
  • “Confidence in the track forecast is still not high,” the NHC bluntly stated.
  • Storm surge flooding will be one of the biggest threats from this storm, as the northern Texas and western Louisiana coastlines are particularly vulnerable to this hazard.
August 24, 2020 at 10:53 PM EDT
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Tracking Laura and Marco

By Jason Samenow

Tropical storm Laura is tracking toward the Gulf Coast while Marco had made landfall near the mouth of the Mississippi at 7 p.m. and was downgraded a tropical depression at 11 p.m. Here are the coordinates for the two systems as of 11 p.m. Monday:

  • Laura was centered 80 miles northeast of the western tip of Cuba, and was moving west-northwest at 20 mph. Maximum sustained winds were 65 mph, unchanged from 8 p.m.
  • Marco was centered 45 miles west of the mouth of the Mississippi River in southeast Louisiana, and was headed west at 9 mph. Maximum sustained winds were 35 mph, down from 40 mph at 7 p.m.
August 24, 2020 at 10:01 PM EDT
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Laura exiting Cuba, entering Gulf of Mexico, where it is primed to intensify

By Jason Samenow

Weather radar over the last hour has shown the core of Tropical Storm Laura departing Cuba and moving over the Gulf of Mexico, likely beginning a phase favorable for intensification.

Interaction with land over the past 36 hours, first over the Dominican Republic, then Haiti and then Cuba, has prevented the storm from significant strengthening, but it still managed to remain a strong tropical storm. In fact, its peak winds even increased slightly Monday from 60 to 65 mph.

Now, over the very warm waters of the Gulf of Mexico, forecasters fear there is little stopping the storm from quickly gaining strength. The official National Hurricane Center predicts Laura will become a hurricane on Tuesday.

The question then becomes how strong of a hurricane. The current forecast is for Laura to peak as a Category 2 with peak winds of 105 when it nears the Texas-Louisiana coastline, but it could become stronger than that.

August 24, 2020 at 9:05 PM EDT
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Marco’s landfall in Louisiana matches record for most U.S. storms coming ashore so soon

By Jason Samenow

When Tropical Storm Marco made landfall at the mouth of the Mississippi River in southeast Louisiana on Monday evening (at 6 p.m.), it became the sixth named storm to come ashore in the continental United States in 2020. That number ties the record, first set in 1886, for most named storms to make landfall by Aug. 24, according to Philip Klotzbach, a hurricane researcher at Colorado State University.

The other storms to make landfall in the continental United States so far in 2020 are:

Assuming Laura makes landfall on Wednesday night or Thursday, as predicted, it will break the record for most named storms to make landfall through August in the continental United States.

When they formed, Laura and Marco were the earliest L and M systems in the Atlantic on record. They are the latest dominoes to fall in a season that has already featured the earliest C, E, F, G, H, I, J and K tropical storms and hurricanes.

August 24, 2020 at 8:10 PM EDT
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Focus turns to Tropical Storm Laura’s intensification rate

By Andrew Freedman

Scientists are poring over data coming in from Tropical Storm Laura via satellites, hurricane hunter aircraft that fly within and around the storm to gather valuable in situ information as well as computer model projections to figure out how strong Laura will get and how quickly.

Researchers told The Washington Post that until the storm can build an inner core of thunderstorms surrounding its low pressure area at the center, it won’t be able to fully tap into the energy provided by the unusually warm Gulf waters below. Once that happens though, model projections are showing Laura may be able to become the season’s first major hurricane in the Atlantic, with an intensity of Category 3 or greater (winds of 111 mph and higher). Periods of rapid intensification are notoriously difficult to forecast, but the signs are there that this storm may jump categories quickly.

If it were to do so, it would raise alarm bells on land near where landfall is predicted, since it would mean potential evacuations on relatively short notice during a pandemic, which is no simple feat.

Climate researchers say hurricanes and typhoons that rapidly intensify are a sign of what to expect with global warming, which is warming ocean temperatures and adding fuel for these storms to feed upon.

August 24, 2020 at 7:00 PM EDT
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U.S. military prepares for Laura

By Dan Lamothe

As the storms closed in, U.S. military officials were making preparation for potential rescues and to keep aircraft safe from harm.

The Coast Guard, which rescued thousands of people in 2017 after Hurricane Harvey flooded the Houston area, has aircraft and shallow-water response boat teams on standby to be used as necessary, said Lt. John Edwards, a Coast Guard spokesman. They could be repositioned as the storm’s path becomes more clear.

“It’s important to remember that the Coast Guard’s ability to respond during the storm will be greatly diminished if not impossible,” Edwards said. “Following the storm, the Coast Guard along with our federal, state and local partners will provide the life-saving support needed in hurricane stricken areas.”

The Air Force has begun evacuating some aircraft from Keesler Air Force Base in Mississippi, Eglin Air Force Base in Florida and the naval air station and joint reserve base in New Orleans, said Lt. Col. Malinda Singleton, a service spokeswoman. More aircraft evacuations are expected as the path of the storms become more clear.

Army officials said on the Facebook page for Fort Polk in Louisiana that they have been tracking weather reports for both storms for several days as soldiers go through training at the service’s Joint Readiness Training Center. “The safety of your Soldiers that are in training at JRTC is our first priority as we monitor the storm forecasts and the leading edge of each storm system as it approaches Fort Polk and Central Louisiana,” the Facebook message said.

A Pentagon spokesman, Lt. Col. Christian Mitchell, said that the Defense Department is monitoring the situation and will be ready to provide support if necessary. Any use of the military will be coordinated through the Federal Emergency Management Agency, which oversees the federal response to hurricanes in the United States and assesses requests from governors.

August 24, 2020 at 5:58 PM EDT
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Heavy squalls from Laura hit Key West

By Jason Samenow

While Laura has directly walloped the Dominican Republic, Haiti, and most recently Cuba, some of its outer bands have lashed the Florida Keys, which are under a tropical storm warning.

The National Weather Service forecast office in Key West clocked a wind gust of 69 mph as a squall swept through Monday afternoon.

“We were just on a south facing waterfront and the waves were pretty incredible,” Ray Warren, a Key West resident, wrote in an email. “This is in an area that doesn’t usually have any surf because it’s within the reef.”

Warren estimated winds were sustained at 35 to 40 mph on the waterfront just before 5 p.m.

The gusty weather observed in the Florida Keys, about 200 miles away from the center of Laura, is a testament to the enormous size of its wind field. In its 5 p.m. advisory, the Hurricane Center wrote that tropical-storm-force winds extended 175 miles from the center.

August 24, 2020 at 5:15 PM EDT
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Hurricane and storm surge watches issued for Gulf Coast as Tropical Storm Laura marches northwest

By Andrew Freedman

The National Hurricane Center issued its first hurricane and storm surge watches for the U.S. coast associated with Tropical Storm Laura. The storm, currently about 40 miles to the east of the Isle of Youth, just south of mainland Cuba, is moving toward the open waters of the Gulf of Mexico and is expected to intensify into a strong Category 2 or 3 storm before making landfall on Wednesday night or Thursday morning.

Computer model guidance has come into better agreement on the likely landfall zone, but it is still a broad area.

A Hurricane Watch is in effect for:

  • Port Bolivar, Tex., to west of Morgan City, La.
  • Galveston and Port Arthur are included in the hurricane watch zone.

A tropical storm watch is in effect for:

  • The area south of Port Bolivar to San Luis Pass, Tex., and from Morgan City to the mouth of the Mississippi River.
  • Houston is included in the tropical storm watch zone.

A storm surge watch is in effect for:

  • San Luis Pass to Ocean Springs, Miss., including Lake Pontchartrain, Lake Maurepas and Lake Borgne for areas outside of the southeast Louisiana Hurricane and Storm Damage Risk Reduction System.

The initial forecast for the maximum storm surge inundation above normally dry land is:

  • High Island, Tex., to Morgan City, including Sabine Lake, Calcasieu Lake and Vermilion Bay: seven to 11 feet.
  • Port Bolivar to High Island: four to six feet.
  • Morgan City to the mouth of the Mississippi River: four to six feet.
  • Mouth of the Mississippi River to Ocean Springs, Miss., including Lake Borgne: three to five feet.
  • San Luis Pass to Port Bolivar: two to four feet.
  • Galveston Bay: two to four feet.
  • Lake Pontchartrain and Lake Maurepas: two to four feet.
August 24, 2020 at 4:38 PM EDT
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Computer model forecasts show substantial threat for Houston and Galveston from Laura

By Jason Samenow

The latest group of computer model simulations suggest that Houston and Galveston, Tex., are plausible landfall locations for Laura and that residents should be preparing for a hurricane.

The map above shows track simulations from the European modeling system, in red, and the American modeling system, in blue. The bold red and blue lines represent the average of each group of simulations.

The European model track simulations are clustered near Houston, while the American model simulations are clustered somewhat to the northeast, near Port Arthur, Tex.

These forecasts suggest that the zone from just north of Corpus Christi, Tex., to just west of Morgan City, La., is most likely to see hurricane impacts based on the latest available data. Houston and Port Arthur are smack in the middle of this zone, while New Orleans has become less likely to endure a direct hit.

As the storm is still more than 48 hours from landfall, this plausible landfall zone could still shift. And it will also probably shrink as the amount of variation among the simulations decreases and the various track forecasts become more tightly packed together, indicating more confidence in the forecast.

August 24, 2020 at 3:34 PM EDT
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Evacuation orders begin in Texas and Louisiana for Laura

By Jason Samenow

Several jurisdictions have begun to issue requests for voluntary and mandatory evacuations in Louisiana and Texas as the threat from Tropical Storm Laura grows.

The storm, predicted to be a Category 2 or possibly stronger hurricane at landfall late Wednesday into Thursday, poses “an increasing risk of dangerous storm surge, wind, and rainfall impacts” according to the National Hurricane Center.

Here are several planned or active evacuation requests:

August 24, 2020 at 2:14 PM EDT
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As Marco disintegrates, NOAA drops tropical storm and storm surge warnings

By Andrew Freedman

The National Hurricane Center has dropped all tropical storm and storm surge warnings for coastal Louisiana as Tropical Storm Marco is torn apart by relentless wind shear in the northern Gulf of Mexico.

On satellite imagery, the center of Marco is a swirl of low-level clouds, while its strongest winds and heaviest rains are displaced well to the northeast, over the Florida Panhandle. This is because of strong upper-level winds that have disrupted the storm, and the Hurricane Center doesn’t see any opportunity for Marco to regain intensity now that it’s so close to shore. This is good news for residents of coastal Louisiana and Mississippi who were preparing for damaging winds and storm surge flooding as recently as Monday morning.

“Based on how quickly the vortex has been spinning down and the anticipated decrease of convection, it is reasonable to assume that sustained tropical storm force winds will no longer reach the northern Gulf Coast,” the Hurricane Center, which is part of the National Oceanic and Atmospheric Administration, said in an online discussion.

August 24, 2020 at 2:06 PM EDT
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Tropical Storm Laura is hugging south coast of Cuba

By Andrew Freedman

Tropical Storm Laura is holding its own despite being so close to land, moving just 15 miles south of Cayo Largo, Cuba, as of 2 p.m. Eastern. The storm is moving west-northwest at a rapid clip of 20 miles per hour, and once it clears the western tip of Cuba, the only impediments to its intensification will be found in the atmosphere. For example, wind shear, or winds blowing with different speeds or direction with height, can inhibit a tropical storm or hurricane from strengthening or even tear it apart.

Officially, the Hurricane Center is forecasting Laura to make landfall somewhere along the Texas or Louisiana coastline on Wednesday night as a Category 2 hurricane. However, forecasters there are cautioning it could grow more intense, and computer models are showing how that could play out. Hurricane and storm surge watches are expected to be issued for the Gulf Coast by Monday evening in anticipation of the storm’s arrival.

August 24, 2020 at 12:58 PM EDT
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Tropical Storm Laura on eerily similar path to deadly 1900 Galveston hurricane

By Jason Samenow

The Weather Channel’s Greg Diamond has pointed out that Tropical Storm Laura is on a similar path to the Sept. 8, 1900, Galveston Hurricane, the deadliest natural disaster in U.S. history.

That storm, a Category 4, was blamed for 8,000 fatalities, although exact estimates vary. Most of the deaths occurred from the storm surge, the rise in water above normally dry land at the coast, which resulted in over 15 feet of inundation. The area was not evacuated ahead of the storm, and as waters rapidly rose, it was too late for many to escape, and there was little high ground to flee toward.

The story of Isaac Cline, the U.S. Weather Bureau meteorologist who attempted to warn Galveston residents about the forthcoming danger the day the storm approached, is chronicled in the popular book “Isaac’s Storm,” by Erik Larson.

Although Laura has followed a track similar to the Galveston storm so far, there remain a wide range of possibilities for its ultimate landfall location, somewhere between Corpus Christi and New Orleans in the Wednesday night through early Thursday time frame. The current National Hurricane Center forecast suggests that the most likely landfall location is near the Texas-Louisiana border.

It’s also not clear whether Laura will be anywhere near as intense as the 1900 hurricane. The current Hurricane Center forecast projects it to make landfall as a Category 2 storm with 105-mph winds, although some computer models suggest it could be stronger. The 1900 hurricane had peak sustained winds estimated between 130 and 140 mph.

Galveston now has a sea wall to protect it to some extent from storm-surge inundation. The judge for Galveston County reportedly declared a state of disaster on Monday afternoon ahead of the storm.

August 24, 2020 at 12:17 PM EDT
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Laura blamed for at least 11 deaths in Haiti and the Dominican Republic

By Jason Samenow

As Laura plowed through the Dominican Republic and Haiti over the weekend, it unloaded torrential rainfall that led to deadly flash flooding.

The Associated Press reported at least 11 deaths from the tropical storm, which caused wind damage in addition to flooding.

“Haitian civil protection officials said they had received reports that a 10-year-old girl was killed when a tree fell on a home in the southern coastal town of Anse-a-Pitres, on the border with the Dominican Republic. Haiti’s prime minister said at least eight other people died as Laura passed by and two were missing,” the AP wrote. “In the Dominican Republic, relatives told reporters a mother and her young son died after a wall collapsed on them.”

The National Hurricane Center had forecast 4 to 8 inches of rain in the two countries, with isolated amounts to one foot that would cause “life-threatening flash and urban flooding, and the potential for mudslides.”

In Haiti, decades of rampant deforestation have contributed to unstable hillsides vulnerable to excessive rainfall.

Social media video showed examples of significant inundation from heavy rainfall in both Haiti and the Dominican Republic.