Large plumes of Saharan Dust have been moving across the Atlantic and now moving into the Caribbean. These dust plumes are very effective in limiting convection in tropical waves and the formation of tropical systems. The very dense area of dust over Puerto Rico is making for a very dust and hazy sky. As this Saharan Air Layer continues westward it will become noticeable across the southeastern United States. It generally cuts down our rain chances for a few days and leads to some stunning sunsets.

Strong wind shear also continues across much of the Tropical Atlantic Basin. Much of the central and western Caribbean into the Gulf of Mexico are virtually convection free with strong wind shear and very limited moisture with westward advancing tropical waves.

The only signs of life in the tropics are well north and not in a favored location for development. An area of low pressure several hundred miles off the coast of Cape Cod has been identified by the National Hurricane Center. They are giving a 20% chance of development over the next 2 to 5 days. Unless it can quickly tap into the warmer waters of the Gulf Stream this low has little chance of developing. Regardless of development it will continue to move over open waters and have no effect on land areas.

Our first tropical system of the season is making a very close pass on the North Carolina coast line. Winds are sustained at 50mph but the majority of the wind and rain with this storm is on the eastern side or the side away from land. Arthur will begin to turn in an easterly direction over the next several hours as wind shear continues to increase. Winds are expected to increase as it begins to transition from a tropical system to a non-tropical low.

The strongest area of deep convection has remained offshore with some occasional rain bands wrapping around to the western side of the storm and moving onshore. Dry air has been wrapping around the southern side of the storm so virtually all the the convection has been limited to the northern half of the storm.

Winds have been gusting close to tropical storm force along the immediate coastline inside of some of the rain bands. With the quick forward speed of Arthur the rainfall amounts will be modest. The immediate coastal towns will see 1 to 3 inches of rainfall. Arthur is just another reminder of how as we “officially” start the hurricane season on June 1st, tropical systems can form prior to the start of the season and can form quickly.