Tropical Storm Marco is weaking, but it’s still set to pack a punch as it approaches Louisiana and the U.S. Gulf Coast for a Tuesday landfall. Hot on its heels, Tropical Storm Laura is set to strengthen to hurricane strength ahead of its own hit on the coast, roughly 48 hours after Marco — and its abundant moisture may have an impact on Canada’s weather by the weekend.
Though briefly a hurricane at its peak over the weekend, Marco is once again a tropical storm as it begins its final approach to the U.S. Gulf Coast.
As of Monday morning, was around 135 km from the mouth of the Mississippi River, with maximum sustained winds of 80 km/h.
Tropical storm and storm surge warnings are in effect for much of the Louisiana and Mississippi coasts, and the storm is already bringing rainfall to those areas ahead of its expected arrival sometime Tuesday morning, with a motion more or less parallel to the coast before a rapid loss of strength.
The storm is expected to bring 75-125 mm worth of rain over the course of its impact, with locally higher amounts up to 250 mm possible as well.
TROPICAL STORM LAURA
Though Marco is already weakening, Laura’s strongest days are still ahead of it, even as it brought torrential rains to Puerto Rico, the Bahamas, and Hispaniola over the weekend.
As of Monday afternoon, the center of Laura is passing near Cayo Largo, Cuba. Laura looks to head through the Caribbean Sea just missing the southern coast of Cuba this afternoon, cross western Cuba by evening, and make its way to the southeastern Gulf of Mexico overnight.
Laura is forecasted to move over the central and northwestern Gulf of Mexico Tuesday night and Wednesday, and reach the northwestern coast of the Gulf of Mexico by Wednesday night.
Once above the Gulf of Mexico on Tuesday, it looks like Laura will intensify. By that time, it appears the tropical storm status will increase to hurricane status, at least reaching the Category 3 level. It’s possible that Laura will reach a Category 4 storm before making landfall along the coast of Texas Wednesday night.
The storm’s exact track is still uncertain, but it seems like landfall will be made between Port Arthur and Corpus Christie, Texas. Houston and Galveston could be near the centre of that area of uncertainty, though the official forecast from the National Hurricane Center is currently further to the east.
“From Wednesday afternoon into Friday, Laura is expected to produce rainfall of 4 to 8 inches, with isolated maximum amounts of 12 inches across portions of the west-central U.S. Gulf Coast near the Texas and Louisiana border north into portions of the lower Mississippi Valley,” the U.S. National Hurricane Center says. “This rainfall could cause widespread flash and urban flooding, small streams to overflow their banks, and minor to isolated moderate river flooding.”
It should be noted that the storm will impact the same region affected by Marco two days prior, worsening the risk of flooding given how waterlogged the region will be.
Beyond, Laura’s remnants look set to track up through the Mississippi Valley, and its moisture may help fuel showers even as far as the Great Lakes, including Ontario.