A Memorial Day Weekend Tropical System For the Southeast U.S.?

By Jeff Masters
Published: 4:13 PM GMT on May 24, 2016

We're fast approaching the official June 1 start of the Atlantic hurricane season, and we already have an area of concern to watch for possible genesis of a tropical depression during the coming Memorial Day weekend. An area of low pressure is expected to form on Friday near to or a few hundred miles north of the Bahama Islands, and this low has the potential for tropical development as it moves northwest towards the Southeast U.S. coast. Sea Surface Temperatures (SSTs) over the Bahamas are about 28 - 29°C (82 - 84°F), which is 1 - 2°C (1.8 - 3.6°F) above average. These waters are plenty warm enough to support formation of a tropical storm. Phase space diagrams from Florida State University have been consistently showing that this storm will be a symmetric warm core system, which is technical lingo for a storm that is tropical in nature, rather than subtropical or extratropical.

Figure 1. Departure of Sea Surface Temperature (SST) from average for May 24, 2016. The Bahamas had SSTs that were 28 - 29°C (82 - 84°F), which is 1 - 2°C (1.8 - 3.6°F) above average. Image credit: tropicaltidbits.com.

Figure 2. Surface pressure (black contours) and 6-hour precipitation (in mm/hr) predicted for Saturday, May 28, 2016 at 2 am EDT (06Z) from the 8 am EDT (12Z) Tuesday, May 24 run of the GFS model. An area of low pressure with the potential to develop into a tropical depression was predicted to be near the coast of South Carolina. Image credit: tropicaltidbits.com.

What the models say: a heavy rain threat for the Southeast U.S. coast
In my 2013 blog post, Genesis of New Atlantic Tropical Cyclones: Which Model Should You Trust?, I explained that we have three models that have proven to be fairly reliable for predicting the genesis of tropical depressions up to four days in advance: the American GFS model, the European ECMWF model, and the British UKMET model. Over the past two days, the GFS and European models have been showing the potential for a tropical depression to form near or to the north of the Bahamas; the UKMET model has merely shown a tropical disturbance forming. The models have widely differing ideas on how much wind shear might be present, so it is too early to say if this weekend's system is a legitimate threat to develop into a tropical depression. The main concern for this weekend's low will be heavy rain over the northwest Bahamas and the Southeast U.S. coast, as the storm likely will not have enough time over water to become a strong tropical storm or hurricane. The GFS model is indicating a possible threat to the coasts of northern Florida, Georgia, or South Carolina early next week, while the European model takes the low farther to the north, to the coast of South Carolina or North Carolina. I'll keep you updated each day this week with the latest prognosis for this potential early-season storm. Should the storm over-achieve and become a tropical storm, it would be named Bonnie.

Jeff Masters

Comments (272) Permalink | A A A
Ad Blocker Enabled
About The Author
Dr. Masters® co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

Recent Articles

A Week of Storminess on the Southern Plains Dryline

With climatology in the driver’s seat, a busy week of potentially tornadic weather will take shape from Nebraska to Texas. This prototypical late-May pattern is being driven by a very slow-moving upper low centered near Montana and an upper trough extending to California. Moderately strong southwest flow ahead of this trough will persist nearly all week across the Southern Plains--a recipe for tornadic trouble this time of year, given the presence of very warm, mo...

Read Article - Comments (204)

Arctic Sea Ice Goes Far Beyond Record Low Extent for May

The sea ice that coats the Arctic Ocean each winter and erodes each summer is going through its most depleted spring since modern observing began. The Danish Meteorological Institute reported the lowest sea ice extent of any April in the Arctic’s 38-year-long satellite record. As luck would have it, the primary satellite sensor used by the National Snow and Ice Data Center (NSIDC) for extent measurement began producing spurious data in April. A similar microwave i...

Read Article - Comments (480)

April 2016: Earth's 12th Consecutive Warmest Month on Record

Keeping a year-long string of record-warm months going, April 2016 was by far the planet's warmest April since record keeping began in 1880, said NOAA's National Centers for Environmental Information (NCEI) on Wednesday. In the NOAA database, April 2016 came in a full 1.10°C (1.98°F) warmer than the 20th-century average for April of 13.7°C (56.7°F), as well as 0.28°C (0.50°F) above the previous record for April, set in 2010. This is a huge margin for breaking ...

Read Article - Comments (366)

Deadly Rains From Tropical Cyclone One Kill 34 in Sri Lanka, Leave 134 Missing

One of the deadliest weather-related disaster of 2016 is unfolding in Sri Lanka, where heavy rains from Tropical Cyclone One have triggered flash floods and landslides that have killed at least 34 people and left 134 missing. The rains began on Monday, when an area of low pressure that formed on the leading edge of the advancing monsoon began to consolidate just to the southeast of Sri Lanka. Hours of torrential rains triggered massive mudslides Tuesday evening that...

Read Article - Comments (75)

Previous Entries