Well school's out for summer like the old Alice Cooper song goes.
And now it's family vacation time down at the beach.
Of course, each summer we have to watch out for tropical storms when making those rest and relaxation plans. It's hurricane season. On average, the Atlantic Basin tropical storm season which covers the Atlantic north of the equator, the Caribbean and the Gulf of Mexico begins June 1st and ends November 30th.
The season usually starts out slow with storms developing in the gulf and Caribbean. Here, the water is warmer than the rest of the Atlantic basin. You need 80 degrees to get the tropical storm process going.
As we move through the summer months, the waters warm in the Atlantic and the storms develop there. The season peaks in early September. By then, storms develop everywhere even off the coast of Africa near the Cape Verde islands. This stage of the Atlantic Basin tropical storm season is called the Cape Verde season.
Then, as we move into Fall, storms tend to develop closer to the US coast until cold fronts invade the tropics.
Storm development begins with a tropical wave or low pressure area.
Once a circulation develops…if the environmental winds are light and waters above 80 degrees, a Depression can form. Winds between 25 and 39 mph are needed.
Above 40 mph, the system becomes a tropical storm and gets a name.
Over 74 mph, it becomes a hurricane.
Above 111 mph, the storm is considered a Major Hurricane. At this level, if the storm moves inland, catastrophic damage over a widespread area becomes more likely.
An average year typically sees 12 named storms, 6 hurricanes and 3 of major status. The average goes back 30 years.
NOAA or the National Oceanic and Atmospheric Administration is forecasting close to average. Their numbers released in late May include 9 to 15 named storms, 4 to 8 hurricanes and 2 to 4 major ones.
Colorado State University is also calling for an average hurricane season with 13 storms, 5 hurricanes with 2 majors.
This year's tropical storm forecast is tied to El Nino plus abnormally warm Atlantic Ocean.
El Nino is the abnormal warming of the equatorial Pacific. We are currently in a weak El Nino, but it's expected to last into the Fall or for most of the hurricane season.
El Nino suppresses tropical activity in the Atlantic with strong environmental winds from the west.
The very warm waters above 80 F may offset El Nino a little concerning storm formation in the Atlantic and the forecasts from NOAA and CSU take that into consideration.
Strong hurricanes can occur in El Nino years. In 1992, we had a strong El Nino. There were only 7 storms that year including one Category 5 Hurricane named Andrew. It wiped out Homestead Florida with almost 200 mph winds. Damage was 27 billion dollars at the time!