FLHurricane.com: Eastern Pacific Begins as El Nino Subsiding

Aloha Friends. As Mike has pointed out today, May 15th marks the beginning of the Eastern Pacific Hurricane Season, although the Central Pacific Hurricane Season, like the Atlantic's, won't begin until June 1st.

The good news for the Eastern and Central Pacific Basins is that the moderately strong El Nino conditions that have prevailed for the past year or so are gradually subsiding. The 2 degrees C temperature anomoly isotherm that had been so prevalent across much of the Eastern and Central Pacific Basins has gradually contracted in horizontal extent and is now present only between about 98 and 110 degrees longitude west, and appears to be rapidly subsiding. (See Attachment)

Unfortunately, this returning to Neutral conditions implies a return to more normal Tropical Cyclone activity in the Atlantic Basin, as other recent posts in these forums have suggested. Indeed, an above normal season is anticipated, as a return to Neutral and possibly even a transition to La Nina conditions by mid-summer could harbinger a return to the busy hurricane seasons we've seen beginning in 1995.

The following is the El Nino synopsis from a May 10th 'expert discussion' issued from the Climate Prediction Center.

-- A transition from El Niño to -neutral is underway.
-- Sea surface temperatures are decreasing across much of the Pacific Ocean.
-- Based on current observations and dynamical model forecasts, a transition to -neutral conditions is expected by June 2010, which will continue into the Northern Hemisphere summer 2010.
-- Although most models predict -neutral conditions, there is a growing possibility of La Niña developing during the second half of 2010.

So all in all, it appears that the Atlantic is likely to be quite busy this season, while the Eastern Pacific will see more normal and possibly less than normal Tropical Cyclone activity. And the Central Pacific, where Hawaii is located, should see *much less* activity this year, compared to last seasons' *very busy* year, which exhibited numerous Tropical Storms and Hurricanes.

There was even a very strong Invest that very nearly became a Tropical Depression in February of this year, about 1200 miles SW of the Hawaiian Islands, but apparently was too far south for the Coriolis Effect to impart sufficient 'spin' for cyclogenesis to occur. Some models were developing it into a TS and tracking it generally towards Hawaii.

As usual, I'll be posting frequently throughout the season on Tropical Cyclone activity in the Eastern, Central and Western Pacific Basins. Everyone is invited and encouraged to post your comments and questions in this "Other Storm Basins" forum, as well.

Edited by CoconutCandy (Sat May 15 2010 10:45 PM)