Alberto headed away from land; TD 2-E a concern for Mexico

Tropical Storm Alberto continues to struggle against strong upper level winds out of the west-southwest that are creating a very high 40 knots of wind shear over the storm. These winds are driving dry, continental air into Alberto, keeping its heavy thunderstorm activity quite limited. While the storm is being helped by the fact it is crossing the warm 27°C (81°F) waters of Gulf Stream today, this is not enough to offset the high wind shear. Small storms like Alberto are highly vulnerable to wind shear, and you can see all the dry air surrounding the storm, which the shear is driving into its core, on water vapor satellite loops. Alberto has begun an eastwards motion away from the coast, and will accelerate to the northeast later today and Tuesday as a trough of low pressure pulls it out to sea. Alberto has likely seen its peak intensity, and will not trouble any land areas. The storm brought up to an inch of rain to the coast near Savannah, Georgia on Sunday.


Figure 1. True-color visible satellite image of Alberto taken by the Aqua satellite at 2:30 pm EDT Sunday May 20, 2012. At the time, Alberto had maximum sustained winds of 45 mph. Image credit: NASA.

Eastern Pacific TD 2-E may become a dangerous hurricane for Mexico
A more significant storm is newly-formed Tropical Depression 2-E in the Eastern Pacific, off the coast of Mexico. The depression is taking its time getting organized today due to its large size, as seen on satellite loops. But with favorable SSTs of 29 - 30°C and light to moderate wind shear in the 5 - 15 knot range expected along its path, TD 2-E should steadily organize on Tuesday and Wednesday, and become Hurricane Bud by Thursday. A trough of low pressure is expected to swing north of the storm late this week, turning TD 2-E to the north to a landfall between Manzanillo and Acapulco, Mexico on Friday. This storm has the potential to be a dangerous hurricane for the Mexican coast.


Figure 2. Sunday's annular eclipse of the sun as seen by wunderphotographer mcgino in Polverada, NM.

Spectacular annular eclipse of the sun on Sunday
On Sunday, sky-watchers along the U.S. West Coast and in Asia were treated to a rare annular eclipse of the sun, where the moon blocked out all but a thin ring of light around the sun. Our wunderphotos gallery has fantastic collection of some great eclipse photos people took. Dr. Cliff Mass' blog has a nice satellite sequence showing the shadow of the eclipse affecting the U.S.

Jeff Masters