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This morning NOAA issued its hurricane outlookfor the 2012 season, suggesting a near-normal hurricane season is most likely.

2012 Atlantic Hurricane Season Outlook: Summary

NOAA’s NOAA definitionsof above-, near-, and below-normal seasons. The Atlantic hurricane region includes the North Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico.

This outlook reflects the possibility of competing climate factors, combined with several circulation and sea surface temperature (SST) features that suggest a less active season compared to many in recent years. Favoring an above-normal season is expected near-average SSTs across much of the tropical Atlantic Ocean and Caribbean Sea(called the Main Development Region, or MDR).

A potentially competing climate factor is the possible development of El Niño during the season. If El Niño develops, it could make conditions less conducive for hurricane formation and intensification during the peak months (August-October) of the season, thus shifting the activity toward the lower end of the predicted range.

If they persist, two other factors that are now present could also compete with conditions associated with the high-activity era. These are: 1) Enhanced vertical wind shear across the MDR, and 2) Cooler-than-average SSTs in the far eastern tropical Atlantic.

Given the current and expected conditions, combined with model forecasts and possible competing factors, we estimate a 70% probability for each of the following ranges of activity during 2012:

9-15 Named Storms,
4-8 Hurricanes
1-3 Major Hurricanes
An Accumulated Cyclone Energy (ACE) range of 65%-140% of the median.
The seasonal activity is expected to fall within these ranges in 70% of 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.

Note that the above ranges are centered near the official NHC 1981-2010 seasonal averages of 12 named storms, 6 hurricanes, and 3 major hurricanes.

This Atlantic hurricane season outlook will be updated in early August, which coincides with the onset of the peak months of the hurricane season.

Federal hurricane scientists predict:
9-15 Named Storms,
4-8 Hurricanes
1-3 Major Hurricanes
The median number of named storms — that’s tropical storms and hurricanes — that have formed during Atlantic hurricane seasons since 1980 is 12, with 6.5 hurricanes and 2 major hurricanes.

The reasons for the near-normal prediction are pretty straightforward: sea surface temperatures in the tropical Atlantic, in contrast to most recent years, are relatively cool in some regions where tropical storms develop, and there’s the potential for the development of El Niño later in the season.

The 2010 season, of course, was incredibly active with 19 named storms.

NOAA’s predictions are generally consistent with those issued by other weather services, which are looking at the same data and drawing conclusions. Here are some of the other predictions made previously about the 2012 Atlantic season:

AccuWeather :
12 named storms
6 hurricanes
2 major hurricanes
ImpactWeather :
10 named storms
5 hurricanes
2 major hurricanes
Gray/Klotzbach :
10 named storms
4 hurricanes
2 major hurricanes
Despite predictions for a near-normal season the 2012 Atlantic year has started off with a bang. Already this season Caribbean disturbance .

Finally, let me not forget to include the standard caveats when it comes to seasonal hurricane forecasting:
1. This is not an exact science, although seasonal forecasters are getting better.

2. Do not confuse seasonal forecasting with the much more reliable predictions made for active storms by the National Hurricane Center.

3. And even if it’s a “quiet” season with only a few storms, it’s a really bad season for you if one of those few storms hits you (see Alicia).