The eastern Pacific hurricane season officially begins on May 15 but once again, like we saw last year, it seems that things will get started a littler sooner than expected.
The NHC is monitoring an area of low pressure well to the south and west of Cabo San Lucas along the Baja peninsula. It currently has a 70% chance of additional development and could become a tropical depression later today.
If it were to strengthen in to a tropical storm, with winds of at least 40 mph, it would take the first name on the 2018 Pacific list: Aletta.
Even if the system (technically designated as invest 90-E) does develop further, it will have zero impact to land but would be an interesting novelty – especially since we saw early season development in the eastern Pacific last year; on this same date ironically. That was TS Adrian and it was the earliest formation of a tropical storm in the eastern Pacific. Adrian formed much closer to land, just offshore of Central America but quickly dissipated.
The eastern Pacific is only marginally favorable right as sea surface temperatures are still warming since we’re only in early May. A favorable upward motion pattern (MJO) in the region, along with other local factors which enhance convection or thunderstorm activity, is likely causing this earlier-than-normal occurrence to take place.
It will be interesting to see what happens as this favorable pattern slowly migrates eastward in to the western Caribbean and Gulf of Mexico towards the end of the month. It would not be surprising to me if we saw a similar flare-up of convection farther east near Central America, either on the Pacific side or the western Caribbean side, in a week or so.
I’ll have more information concerning 90-E in a video discussion that I will post later this afternoon.
8:50 AM ET May 9