Summer could be Windy and Rainy

The thought of summer conjures up visions of grills, lemonade, l and gazing at the shore or other popular vacation haunts. Naturally this implies sunny skies, and so we turn to meteorologists with high expectations. Predicting summer weather in the US is more difficult than winter because there is no jet stream to stabilize the atmosphere and make things more predictable. Even so, meteorologists believe that it's looking as if the southern part of the US will have a hotter than average summer and the Gulf and Atlantic coastal regions will be threatened by a higher number of hurricanes than usual.

During the winters, the jet stream will track storms systems across the country in predictable patterns which are influenced by ocean currents. However, during the summer months the jet stream shifts northward into Canada and there are no longer term weather trends to aid forecasters. What tends to dominate summer weather are short term weather patterns driven by isolated thunderstorms. The thunderstorms themselves are controlled by localized heat and humidity.

To predict this summer's likely weather, one has to look to long weather patterns over about a decade and look for trends there. These indicate warmer temperatures in the south during the summer. This isn't related to global warming though, rather its a long term trends and that prediction applies to only the southern US, not the northeast, which has been somewhat of a puzzle to forecasters. What are they predicting for the northeast summer? They're not. All winter long they predicted warmer weather and we ended up with a colder than normal winter. However, the predictions regarding hurricane season this summer will affect our weather.

Hurricane season officially begins June first, but typically doesn't get really active until late summer. It officially ends November 30. This year however, both National Oceanic and Atmospheric Administration (NOAA) and the renowned forecast team at Colorado State University in Fort Collins led by atmospheric scientist William Gray are calling for above normal levels of activity.

Names for the impending hurricanes have already been chosen. This year we can look forward to Ana, Bill, Claudette, Danny, Erika, Fabian, Grace and their other friends which may form in the Atlantic basin. Predictions are calling for 11 to 15 named tropical storms. Of these, it is estimated that 6 to 9 will form into hurricanes and 2 to 4 will be classified as major.

During the 2002 hurricane season there were 12 named tropical storms, 4 hurricanes and 2 major hurricanes. El Nino was responsible for fewer storms in 2002, but that system is gone now, so this year the number of hurricanes will likely be higher.

The North Atlantic ocean is continuing its decades long trend of being warmer. This was also the case during the 1950's and 1960's, except for the years that El Nino influenced the weather, there were more hurricanes than usual.

More specific estimates regarding hurricanes say that there is a 68 percent chance that one of the major hurricanes will make landfall somewhere along the Gulf or Atlantic US coasts. A more active hurricane season usually means that the Atlantic and Gulf coast regions will have a wetter than normal late summer and autumn.

There is a factor which could make the hurricane season even worse: La Nina. La Nina is characterized by colder than normal temperatures in the equatorial Pacific region, the opposite of El Nino which brings warmer temperatures. If La Nina becomes a factor, it will make our hurricane season even worse.

NOAA predicts there is a 70 percent chance of La Nina forming. If it does, in addition to enhancing the hurricane season, the southeast US will likely have a drier, warmer winter.

In spite of summer forecasting being more difficult, NOAA has actually had a good record of predicting it. If they're correct about this summer, umbrellas and other rain gear may be replacing those visions of grills and cool drinks!

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