Sub-tropical Storm Andrea

I've never heard of a sub-tropical storm? What does that mean? Kudos to the DU'er who called this one a few days back.



What began as a mid-latitude or extratropical low pressure system has transitioned to a subtropical storm named Andrea. A tropical storm watch has been posted from Altamaha Sound, Georgia southward to Flagler Beach, Florida.

Andrea has maximum sustained winds of 45 mph and little change of strength is forecast. The storm is located about 150 miles northeast of Daytona Beach, Florida and is moving very slowly towards the west at 3 mph. The center of Andrea is forecast to remain offshore through at least tomorrow morning and possibly for the remainder of its lifespan.

The greatest impacts from this storm have likely peaked during the past two days (before it was even given a name) but a few tropical storm-force wind gusts are still possible today especially along the South Carolina coast. Although wave heights are on the decline today, they'll still be formidable especially along the North Carolina coast with breakers of 8 to 12 feet. Minor to moderate beach erosion is still possible and the risk of rip currents will remain high through at least Thursday.

Coastal showers will move onshore from time to time today and Thursday especially along the South Carolina, Georgia, and northeastern Florida coast. Unfortunately for the arid Southeast, any bit of rain is beneficial but it will likely not be a soaking rainfall. The rain that does fall may not be enough to help firefighters battle the fires over southeast Georgia and northern Florida.

This storm, in whatever incarnation, has had quite the history already. The storm began on Sunday afternoon as an area of low pressure developed a few hundred miles off the North Carolina coast. It quickly strengthened and, along with a bullish high pressure system located over northern New England, created a very tight pressure gradient.

On Monday, the tight pressure gradient led to strong, persistent northerly and northeasterly winds along the Southeast coastline especially over eastern North Carolina. Peak winds on Monday ranged between 45 and 55 mph. Hatteras, for example, had a peak gust of 51 mph.

High waves were and have been the most visible aspect of the storm. A buoy stationed 150 nautical miles east of Cape Hatteras documented 42 foot waves on Monday afternoon.

Along the immediate coast, the largest breakers have been found along the North Carolina coast. Waves are forecast to break between the 8 to 12 foot range during Wednesday not only for N.C. but also for much of the South Carolina coastline. Wave heights will be lower, between 1 to 5 feet, from coastal Georgia southward along Florida's coast.

Along with the thunderous waves, minor to major beach erosion and coastal flooding has also been documented. Coastal overwash spilled on top of U.S. 12 in the Outer Banks and portions of the road were at one point impassable on Monday. Major beach erosion and coastal flooding was also reported in Jupiter, Florida on Tuesday. The National Weather Service out of Miami reported a life guard office and garage were nearly washed into the ocean and about 100 feet of coast has been eroded. The road leading to Jupiter Inlet has since been closed. The pier at Flagler Beach (20 miles north of Daytona Beach) was also closed on Tuesday for a period of time.

During the overnight hours of Monday into Tuesday, the extratropical low evolved into a subtropical storm. A subtropical storm has a few characteristics of both an extratropical low and a tropical cyclone. First, it has convection, or thunderstorm activity, around a well-defined center of circulation. Second, it has become detached from its associated fronts (cold, warm, occluded). Finally, it has sustained gale/tropical storm force winds.

Unlike a tropical cyclone, this is a cold-core system and its strongest winds are found miles away from the center of circulation; not tightly wrapped around the center.

http://www.weather.com/newscenter/tropical/index.html?from=hurricane_tracker

We better get ready to rumble...whether we have FEMA or not.:scared:

if pig boy's house got swamped by a 100 foot tidal wave and he survived, but couldn't get help becuase the Florida National Guard is in Iraq. Give OxyBoy a megaphone "There is no global warming!"

and then shrugged his shoulders because it couldn't be. The weather service didn't call it.

They are scared to death that the season is starting Early!!!!!

"A subtropical cyclone is a weather system that has some characteristics of a tropical cyclone and some characteristics of an extratropical cyclone. They can form in a wide band of latitude, from the equator to 50°."

If it strengthens, a subtropical storm can become a tropical storm and then a hurricane. Doesn't hurricane season officially begin on June 1? But with global warming, I'm sure the season can begin earlier and last longer. Just like tornadoes. Last year, we had serious tornadoes here in Kansas about two weeks earlier than what was considered to the official start of tornado season.