Tag Archives: tropical disturbances

Three Tropical Waves

There are three notable tropical waves spread across the Atlantic and Caribbean this morning.  The first wave is over the eastern Caribbean Sea.  Thunderstorm activity has been gradually increasing with this wave and there may be an 850 mb vorticity center near latitude 12°N and longitude 62°W.  The wave extends northward to just east of Puerto Rico.  The wave is moving westward.  The models are not forecasting development of a tropical cyclone out of this wave at this time, but it may bear watching if the convection continues to increase.

A second tropical wave is located midway between Africa and the Lesser Antilles.  A low pressure system is located in the wave near latitude 12°N and longitude 36°W.  Cyclonic turning of the clouds is evident in satellite loops.  Drier air in the northern portion of the wave is limiting convective activity to the southern half of the cyclonic circulation.  Some runs of the GFS indicate modest development of the low pressure system as it moves westward.  In other GFS runs the low weakens before it reaches the Lesser Antilles.

A third tropical wave is located half way between Africa and the Cape Verde Islands.  A low pressure system is located in the wave near latitude 15°N and longitude 20°W.  Convection was impressive last night when the low first emerged from Africa and moved over the Atlantic.  However, strong easterly winds in the upper levels sheared the top off of this system and only a low level cyclonic circulation remains.   Earlier model runs indicated possible development of a tropical cyclone out of this wave, but more recent runs indicate that the upper level shear will continue and prevent development.