The tropics are quiet… for now

What’s left of Elsa has evolved into a North Atlantic disturbance and will be swept away by the northern jet stream.

Elsewhere the tropics are quiet, as they normally are in the middle of July.

Over the last busy couple of decades of tropical systems, according to Dr. Phil Klotzbach of Colorado State University, the average date for the 5th named storm of the year has been August 20th. Elsa came along on July 1st, so we are way ahead of schedule, even by modern standards.

Currently the El Niño/La Niña cycle is in a Neutral Phase, which makes predicting how busy the rest of the season is going to be very hard. Historically, Neutral-Phase years have been both very busy and pretty quiet. On either end of the scale, we have more confidence in the forecast. El Niño years normally have fewer hurricanes, and La Niña years, like last year, generally have more.

The tropical Atlantic is on the cool side, however, compared to normal. And it’s much cooler than last year. So that might have a modifying influence on the number of systems that form, or how quickly they strengthen.

On the other hand, the disturbances that have come off of Africa this year have been quite robust. We’ll see if that trend continues. Bigger disturbances often have an easier time spinning up over the tropical waters.

For now, however, the upper-level winds are hostile over most of the tropical belt, so no tropical development is expected through the middle of next week, at least.