Hello, and welcome to my official mid-season seasonal forecast for the 2011 Atlantic Hurricane Season and the 2011 Pacific hurricane season. This is my only mid-season forecast and it will not be updated at any time (the forecast will not be changed, any other things such as anomalies and prose corrections and additional sections will). Skip down to the last section to see the actual forecast.
Current El-Nino/La-Nina Anomalies
In 2010, a fairly strong La Ninia continued into 2011, however, it started to weaken as the winter months passed, approaching a neutral state by June. This weakening La Nina caused dry air and westerly winds, making the first half of the 2011 Atlantic Hurricane season weak and the Pacific strong. A neutral state for both the Atlantic and the Pacific is expected for the rest of 2011.
So Far in the Basins
For the Atlantic, there have been a total of 7 named storms but no hurricanes. This marks the first time since 2002 that this has happened. Most of these storms have also been relatively weak, with wind speeds ranging in the 45-65 mph range and a pressure range of >990mbar. However, these weak storms have been forming at a record pace. Don was the 12th earliest date that the foruth storm formed. Emily was 8th, Franklin 5th, and Gert 4th. Due to the short lived and weak systems, the ACE remains unusually low at 10.9, the largest ACE in a single storm so far is Bret, with an ACE of 2.95. A storm of similar ACE the previous year would be Fiona.
The Pacific has seen much more stronger storms thus far, but not many storms in contrast to the Atlantic have formed yet. There has been a total of 5 named storms, of which all have been hurricanes, and 3 major hurricanes, each peaking at category 4 strength. This is the only time that the first 5 consectuive systems became hurricanes. The number of strong systems accounts for a high ACE of 46.6, the largest ACE in a single storm so far is Eugene, with an ACE of 14.9. A storm of similar ACE the previous year would be above Darby but below Celia.
Overall:114% above average*
17 total systems (dropping 2 depressions)
15 named storms (above average, 145.8%)
6 hurricanes (average, 101.6%)
2 major hurricanes (near average 86.9%)
An ACE of 70-110.
The strongest storm peaking as a category 4 with wind speeds of 140 mph and a min. pressure of 937 mbar.
Due to the quick pace of the 2011 season, the number of systems should be above average, at 17, although there is no reason why it shouldn't be over 20, as said in the forums. The quick pace of the storms makes it hard to predict. The number of hurricanes and major hurricanes remains low and in disagreement with the other official forecasts due to the steadily weakening La Nina and unfavorable conditions in many locations, offsetting above average SSTs. The major hurricane forecast is also low because of the failure in the Atlantic to produce one, despite a La Nina. Now we are moving to more neutral conditions, so the stat is low. However, I may be wrong since neutrality in the basins seems to be the forecast for the rest of this year, and maybe even a returning La Nina has an equal percentage of happening as a continuing ENSO-Neutral.
Overall:148% above average*
18 total systems (dropping a depression)
17 named storms (above average, 108.9%)
12 hurricanes (above average, 139.5%)
8 7 major hurricanes (hyperactive, 195.1%)
An ACE of 140-175.
The strongest storm peaking as a category 5 with wind speeds of 165 mph and a min. pressure of 925 mbar.
In a La Nina, the Pacific was able to field 5 hurricanes and 3 major hurricanes. As ENSO-Neutral is here, there is no reason why the Pacific shouldn't perform even better. Expect a hyperactive season in the making.
Any Top Hurricanes (Category 5)?
My forecast calls for not too much surprises such as sudden category 5s. The percentage of a category 5 in the Atlantic in my forecast is 20%. In the Pacific it is 54%.
Pondering on Possibilities... (NO DOOMCASTING HERE!!)
A United States Major Hurricane Strike (Atlantic)
Many think that the United States is overdue for a major hurricane strike that will wake up the public. The last major hurricane to hit the U.S was Wilma in 2005, which hit Florida as a category 3. However, if you consider Hurricane Ike of 2008 a major hurricane knowing how bad it was, then that would be the last one. However, 3 or 6 years is still considered a long time. Last year was a luck strike, so many hurricanes and not a single hurricane strike. So what's my forecast? The United States probably won't get so lucky this year. I am looking for 1 strike by a major.
3 of a Kind (Pacific)
It has never happened before, but can the Pacific perfect the record? 2009 spat out a category 5 in a strong El Nino. Despite how poor the season was, 2010 spat out a category 5 in the face of strengthening La Nina conditions. Can 2011 bring out the load in an ENSO-Neutral? Get ready folks, the chance lies flat on the 50/50.
*The overall seasonal activity for the year. Assuming that named storms are worth 1 point, hurricanes 2, and major hurricanes 4, we can decide the overall seasonal activity for the year. Depressions are worth nothing.
-The averages calculated for the Atlantic are 1950-2000, the Pacific is 1981-2000.