Sunday, May 10, 2015

Ana Makes Landfall and Weakens to a Tropical Depression

Jon Erdman
Published: May 10,2015



 

Highlights

  • The National Hurricane Center downgraded Ana to a tropical depression at 2 p.m. EDT on Sunday.
  • Ana made landfall as a tropical storm between Myrtle Beach, South Carolina and North Myrtle Beach, South Carolina at 6:00 a.m. EDT on Sunday.
  • According to hurricane specialist Michael Lowry of The Weather Channel, Ana is the second earliest landfalling tropical storm on record in the Atlantic. 
  • Ana will continue to weaken as it slides northeastward from eastern North Carolina through southeast Virginia into Monday.
  • The coastal Carolinas will continue to see the most direct impacts into Sunday night, including bands of locally heavy rain, some strong wind gusts, minor coastal flooding, dangerous rip currents and beach erosion. Some rain and gusty winds will also affect parts of southeast Virginia by Monday.
(LATEST NEWS: Ana's Impacts in the Carolinas)

Latest Status

Infrared Satellite: Tropical Storm Ana

Radar, Current Winds

Projected Path

Rainfall Potential

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Where's Ana Headed?

Ana's center of circulation finally made landfall near Myrtle Beach, South Carolina on Sunday morning with top sustained winds of 45 mph. After moving slowly inland for several hours, the National Hurricane Center downgraded Ana to a tropical depression early Sunday afternoon.
(FORECASTS: Myrtle Beach | Charleston | Wilmington | Hatteras)
Bands of rain and some strong wind gusts will pester parts of northeast South Carolina and eastern North Carolina through Sunday night.
Although Ana is now inland, onshore gusty winds will continue along the southern coast of North Carolina, spreading northward into the Outer Banks and Virginia Tidewater through Monday.
(INTERACTIVE: Coastal Carolinas Radar Loop)
By Monday night, a southward dip in the polar jet stream will catch hold of what's left of Ana and finally whisk it away into the Atlantic.

Potential Impacts

Rain/flood threat: Bands of rain continue to move into parts of eastern Carolinas. Areas of rain may linger in the eastern Carolinas through Monday, eventually spreading into parts of Virginia through Monday. The greatest potential for locally heavy rain and flash flooding is in far eastern North Carolina and northeast South Carolina.
Winds: Gusty winds will continue in coastal North Carolina and northeast South Carolina while spreading northward to southeast Virginia through Monday. Some gusts over 40 mph are likely, at times. Some downed tree limbs and sporadic power outages are possible, but the threat of widespread damaging winds and numerous power outages appears low.
High Surf/Rip Currents/Coastal flooding: High surf, rip currents, some coastal flooding and beach erosion from the northern South Carolina coast to the southern North Carolina coast (Hatteras south) continues possibly through Monday, particularly in areas where onshore flow persists the longest (southern North Carolina coast). The combination of storm surge plus normal tides may lead to water levels 1-2 feet above ground near high tide from the southern Outer Banks to South Carolina.
Tornadoes: A few brief tornadoes are possible Sunday into Monday from northeast South Carolina to eastern North Carolina.

Ana History

Ana originally formed as a subtropical storm off the coast of the Carolinas late Thursday night. For more on what a "subtropical" cyclone is, scroll down the page a bit.
Early Saturday morning, the National Hurricane Center said that Ana had made a complete transition from a subtropical storm to a full tropical storm. This was based on the fact that shower and thunderstorm activity was now more collocated with the center of circulation, which is a characteristic of tropical storms.
Ana finally made landfall between Myrtle Beach and North Myrtle Beach in South Carolina at 6:00 a.m. EDT on Sunday. The National Hurricane Center downgraded Ana to a tropical depression at 2 p.m. EDT on Sunday.
A wind gust to 60 mph was reported at a buoy south-southeast of Cape Fear, North Carolina on Saturday evening.
On the coast, winds have gusted up to 59 mph near Southport, North Carolina, and up to 55 mph at the Ocean Crest Pier on Oak Island in North Carolina.
In South Carolina, a peak wind gust of 50 mph was measured in North Myrtle Beach early Sunday morning.

Tropical or Not?

The low started out not as a typical low-pressure system with fronts you may see over, say, the Plains states. Nor was it a tropical depression or storm like you see in the Atlantic or Pacific Oceans in summer.  It was a combination of those, called a subtropical cyclone.
Our friends at Weather Underground have a full explanation of subtropical cyclones. Basically, a subtropical depression or storm exhibits features of both tropical and non-tropical systems, with a broad wind field, no cold or warm fronts, and generally low-topped thunderstorms spaced some distance from the center.
Subtropical cyclones typically are associated with upper-level lows and have colder temperatures aloft, whereas tropical cyclones are fully warm-core, and upper-level high-pressure systems overhead help facilitate their intensification.
Because of this hybrid nature, the National Hurricane Center still issues advisories and forecasts (i.e. projected path) for subtropical depressions and storms and assigns a number or name much like a regular tropical depression or tropical storm.
Occasionally, if thunderstorms cluster close enough and persist near the center, latent heat given off aloft from the thunderstorms can warm the air enough to make the storm a fully tropical storm. As mentioned before, this is the case with Ana.
Tracks of May named tropical cyclones near the Southeast U.S. coast from 2007-2014.

It's Happened Recently

Some recent Atlantic hurricane seasons have jumped the June 1 starting gun.
(MORE: When Hurricane Season Starts Early)
Most recently, in May 2012, a pair of tropical storms, Alberto and Beryl, both formed off the coast of the Carolinas, Georgia and north Florida.
Beryl washed out the Memorial Day weekend, and was the strongest tropical cyclone to make a U.S. landfall before June 1 on record, with 70 mph maximum sustained winds.
In fact, Beryl made the transition from a subtropical to tropical storm prior to landfall, exhibiting an eye and eyewall on radar, according to Ostro.
Five years earlier, a cut-off low-pressure system off the Southeast coast morphed into Subtropical Storm Andrea. Before officially gaining the subtropical designation, the wrapped-up low was responsible for a 2-3 foot storm surge in St. Johns and Flagler Counties in Florida. A surfer and four crew members of a sailing vessel lost their lives in high surf from Andrea.
There was even an Atlantic tropical storm in late April 2003, ironically also named Ana.
Since 1950, eight subtropical depressions or storms have formed before May 7th, according to Dr. Matt Sitkowski, science and weather content coordinator.
In all, there have been 39 Atlantic tropical or subtropical cyclones that have formed before June 1 since 1851, according to hurricane specialist Michael Lowry. Thus, you can expect one of these pre-June 1 systems once every four years, or so, on average.
More importantly, there's no link between an early start and an active season. Lowry says only 38 percent of early-starting Atlantic hurricane seasons ended up with above-average numbers of named storms.
Meteorologist Chris Dolce contributed to this report.

MORE: Hurricane Strikes By County, Parish

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