Category 1 Hurricane Irene weakened from a category 2 Tuesday afternoon, but according to meteorology Assistant Professor Anantha Aiyyer , the storm is likely to regain strength.

“Hurricane Irene is entering into an environment that is very favorable for development, but it’s not too intense now,” Aiyyer said.

Irene became a hurricane Monday after exceeding 74 miles-per-hour.

According to David Church, graduate student in marine, earth and atmospheric sciences and member of the tropical meteorology group, Hurricane Irene is a typical storm of this hurricane season.

“The sea surface temperatures are high, between 28 and 29 degrees Celsius [82-84 degrees Fahrenheit],” Church said. “Anything above 26 degrees is warm and favorable for a storm like this.”

Storms need energy, and hurricanes rely on warm water. This fuel, according to Church, drives the cycle of the winds and the greater the temperature of the water, the more fuel available to the storm. High water temperatures correspond directly with the progression of hurricane season.

“End of August, early September we get into the peak of hurricane season,” Church said.

Although Irene, which progressed from a tropical storm, to a category 2 and currently down to a category 1 is projected to intensify the closer it gets to the N.C . coast.

“When you have a storm like this, which is forecasted to be a larger than average, you have to pay close attention to the various factors the drive it,” Church said. “It can very well pick up energy and increase.”

Governor Bev Perdue urged N.C . residents Tuesday afternoon to prepare for the storm and to stock up at least three days of food and water.

“Our state’s veteran emergency management team is ready for Irene, but our fellow North Carolinians need to be just as prepared,” Purdue said. “If you need tips or information on any of your preparations, please go to www.readync.org.”

Students from the coast may expect family to come to Raleigh and the Piedmont to avoid the high winds, but Aiyyer warned or inland flooding.

“Make sure to avoid low lying areas of topography and also creeks and streams,” Aiyyer said. “We may not experience the same winds of the storm, but it is expected to see a lot of rainfall.”

Alton Russell, a sophomore in biomedical engineering, is from Wilmington, N.C . and has experienced hurricanes Fran, Bertha and Floyd.

“I remember boarding up windows, filling up our bathtub with water and loading up on batteries and flashlights,” Russell said. “I honestly don’t know what my family is preparing to do for Irene, but I’m sure we have plenty of practice.”

The trajectory of the hurricane is not expected to veer off course, according to Aiyyer , but weather is a fickle thing.

“All I can recommend is to stay posted to local news and keep following the storm,” Aiyyer said. “There are many factors that contribute to the storm, but nothing beats updated and new information to base one’s decisions.”

ALT:

Tropical Depression Irene: Maximum of 38 mph

Tropical Storm Irene: 39 to 73 mph

Category 2 Hurricane Irene: 96 to 110 mph

Category 1 Hurricane Irene: 74 to 95 mph

The cycle of a hurricane

Before a storm, three things are requires: heat, water and low pressure.

As the wind speed picks up, the storm takes mist off the ocean surface and picks up a lot of moisture.

This moisture, water vapor technically, comes from hot surface water above 79 degrees Fahrenheit, and releases energy into the atmosphere.

This release of energy translates to increase in heat. Hot water turns to hot air.

Heat in the atmosphere lowers pressure, creating stronger and faster winds. The lower the pressure, the more intense the storm.

As storm winds intensify, the hurricane picks up more moisture.

Source: David Church