Marco downgraded to a Tropical Storm

Track still has system zeroed in on Gulf Coast of Louisiana

Tropical Storm Marco (Copyright 2020 by WJXT News4Jax - All rights reserved.)

Now Tropical Storm Marco is expected to reach the Gulf Coast Monday night into Tuesday.

Marco is feeling the effect of strong southwesterly shear. The center, as identified by an Air Force Reserve Hurricane Hunter aircraft, is displaced to the southwest edge of the convective canopy.

Marco is centered about 185 miles SSE of the mouth of the Mississippi River with maximum sustained winds of 70 mph. It’s moving to the north-northwest at 12 mph. Lowest pressure is 991 mb.

Marco will be susceptible to rapid changes in structure and intensity until it reaches the northern Gulf Coast.

Tropical Storm Marco (TropicalTidbits)

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NHC’s 11 p.m. advisory discussion:

“Key Messages:

1. Strong winds, life-threatening storm surge, and heavy rainfall are expected from Marco along portions of the Gulf Coast beginning on Monday. Interests in these areas should follow any advice given by local government officials.

2. Tropical Storm Laura could bring additional storm surge, rainfall, and wind impacts to portions of the U.S. Gulf Coast by the middle of the week. This could result in a prolonged period of hazardous weather for areas that may also be affected by Marco. Interests there should monitor the progress of Marco and Laura and updates to the forecast during the next few days.”

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A deep-layer trough over the Gulf of Mexico is expected to become the main driver in the coming days, causing the cyclone to track northward and into an area of wind shear which will keep Marco from strengthening rapidly, but he could still become a hurricane.

Marco is expected to produce 1 to 2 inches of rain across Jamaica and northern Nicaragua, and 2 to 4 inches over portions of Honduras through Saturday. The Eastern Yucatan Peninsula may see up to 6″ of rain as Marco slides by.