CYCLONIC FURY

Sea surface temperatures in the Atlantic are slowly warming up, while wind shear is slowly decreasing. The Atlantic basin is not quite ready for tropical cyclones yet, but should be fairly soon. Each Friday when a storm is not active, I will do a detailed analysis of the Atlantic, including sea surface temperatures and anomalies, wind shear, and convective activity.

SEA SURFACE TEMPERATURES 

Sea surface temperatures in the Atlantic continue to slowly warm up, with the 26°C isotherm now stretching northward into the central Gulf of Mexico. 26°C SSTs have now also extended into parts of the Gulf Stream. The warm-up should accelerate in the next few weeks as we approach the official start of the 2017 Atlantic hurricane season on June 1.

Sea-surface temperature anomalies remain positive throughout the Atlantic Main Development Region (MDR) and Caribbean, but are below average in the western subtropical Atlantic and north Atlantic. The positive anomalies in the Atlantic MDR are usually a positive factor for tropical cyclone development; however, the cooler than normal water in the far north Atlantic is not. The sea surface temperature anomalies will continue to need to be monitored as we approach the season – anomalies in the MDR are especially important for the activity of an Atlantic hurricane season!

WIND SHEAR

Wind shear remains unfavorable across nearly the entire Atlantic basin, but this is perfectly normal for May. Wind shear should begin to decrease quickly as we get into June and July. This high shear, along with an unfavorable phase of the Madden-Julian Oscillation, should keep the Atlantic quiet for at least another 10 days.

AFRICAN TROPICAL WAVES

The African wave train is fairly quiet at the moment, likely a result of sinking air produced by the unfavorable Madden-Julian Oscillation phase. However, a possible tropical wave recently exited the coast, and is currently accompanied by modest deep convection. However, the wave is not expected to develop into a tropical cyclone due to unfavorable conditions in the Atlantic typically seen this time of year. We should see weak tropical waves continuing to exit Africa every few days or so for the next couple of months, before we begin to see stronger tropical waves by late July.

I’ll be back with another post tomorrow.