Thursday, August 04, 2011

NOAA Issues Updated 2011 Atlantic Hurricane Outlook

 

 

 

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Earlier today I reported on Colorado State University’s updated 2011 Hurricane forecast (see Dr. Gray’s Tropical Update & Waiting For Emily To Curve) which calls for an above average hurricane season featuring 9 hurricanes (average is 5.9), 16 named storms (average is 9.6).

 

This afternoon NOAA has released their updated analysis of the 2011 Atlantic Hurricane season as well, increasing very slightly their earlier predictions (see see NOAA Issues 2011 Atlantic Hurricane Outlook) released in May.

 

They too are calling for an above average hurricane season.

 

The following are excerpts from an announcement released today by the National Weather Service’s Climate Prediction Center.

 

NOAA PRESS RELEASE

NOAA 2011 Atlantic Hurricane Season Outlook Update

Issued: 4 August 2011

Realtime monitoring of tropical Atlantic conditions
Realtime monitoring of tropical East Pacific conditions

Atlantic Hurricane Outlook & Seasonal Climate Summary Archive

The 2011 Atlantic hurricane season outlook is an official product of the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (CPC). The outlook is produced in collaboration with scientists from the National Hurricane Center (NHC) and the Hurricane Research Division (HRD). The Atlantic hurricane region includes the North Atlantic Ocean, Caribbean Sea, and Gulf of Mexico.

Interpretation of NOAA's Atlantic hurricane season outlook
This outlook is a general guide to the expected overall activity during the upcoming hurricane season. It is not a seasonal hurricane landfall forecast, and it does not predict levels of activity for any particular region.

<SNIP>

2011 Updated Atlantic Hurricane Season Outlook: Summary

NOAA’s updated 2011 Atlantic Hurricane Season Outlook calls for an 85% chance of an above-normal season, and a 15% chance of a near-normal season. There is no expectation for a below-normal season. Therefore, 2011 is expected to become the twelfth above-normal season since 1995. This updated outlook reflects a higher likelihood of an above-normal season compared to the pre-season outlook issued in May, which indicated a 65% chance of an above-normal season. See NOAA definitions of above-, near-, and below-normal seasons. The Atlantic hurricane region includes the North Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico.

<SNIP>

The 2011 season is expected to be comparable to a number of active seasons since 1995. We estimate a 70% probability for each of the following ranges of activity during 2011:

  • 14-19 Named Storms,
  • 7-10 Hurricanes
  • 3-5 Major Hurricanes
  • An ACE range of 135%-215% of the 1981-2010 median.

The seasonal activity is expected to fall within these ranges in 7 out of 10 seasons with similar climate conditions and uncertainties to those expected this year. These ranges do not represent the total possible ranges of activity seen in past similar years.

 

The official NHC seasonal averages are 11 named storms, 6 hurricanes, and 2 major hurricanes.

(Continue . . . )

The outlook from NOAA generally matches the forecast released yesterday by Dr. Gray’s team at Colorado State University.

If they prove correct, it would seem that we’ve got a busy 3 or 4 months ahead.