The east Pacific hurricane season officially began on May 15. So far, we have not had a named storm in that region but it’s still early. I am seeing signs that point to a change in the pattern which should allow for some activity to begin flaring up in the coming days.
As for the Atlantic, the season begins on June 1 but we’ve already had one tropical storm: Ana. Right now, there are no indications of anything trying to organize on the Atlantic side so I will focus on the east Pacific.
As of this morning, the NHC was outlining two areas of disturbed weather, both well to the southwest of Mexico, that have potential for additional development. The eastern most disturbance seems to have the best chance right now as it moves generally westward over the open waters of the Pacific.
The Pacific is now in an El Niño state which means that water temps along the Equator and then several degrees of latitude north (not so much south) are quite a bit warmer than normal.
Add to the El Niño the fact that a more favorable MJO or upward motion pattern is setting up and we have the makings of a busy time coming up for the eastern Pacific. The MJO can be thought of as a period of enhanced upward motion in the atmosphere, mainly in the tropics. Since tropical storms and hurricanes need vertical motion to thrive, a favorable upward motion pattern helps this process and leads to more convection (thunderstorms) over the tropics. Both the GFS and the ECMWF global models agree that a favorable MJO pattern is setting up shop across the region. This should act to enhance the probability for tropical storm formation in the region.
Fortunately, what ever does manage to get going is likely to remain far away from land areas due to a steering pattern that will keep any storms or hurricanes moving generally westward.
We are likely going to see quite a busy east Pacific hurricane season, similar perhaps to last year. It won’t be long before we see development closer to Mexico but for now, the action is taking root much farther to the southwest and is of no concern. It does mean, however, that the hurricane season is about to commence beyond just a point on the calendar. Pacific Mexico residents and tourists alike will need to be ready this season as El Niño years can feature powerful hurricanes due to the warmer water temperatures.
I will have more on the east Pacific activity throughout the weekend.
M. Sudduth 8:40 AM ET May 22