Tuesday, October 4, 2016

Hurricane Matthew Begins Slow Trek Through Bahamas; Hurricane Warnings Issued in Florida

October 4,2016
Hurricane Matthew made landfall near Juaco, Cuba, around 8 p.m. EDT Tuesday evening, and the Bahamas are next in line for hurricane-force and tropical storm-force winds.
(MORE: Hurricane Central | Interactive Storm Tracker Map)
Matthew is increasingly likely to have significant impacts along the Southeast U.S. coast later this week. Those impacts may start to arrive in Florida as early as Thursday, potentially spreading northeast to coastal Georgia and the coastal Carolinas Friday into the weekend.
All interests in the coastal Southeast states should continue to monitor the forecast closely and make necessary preparations for a hurricane.
(MORE: U.S. Impacts From Matthew)
A hurricane warning has been issued for the east coast of Florida from Golden Beach, Florida, to Sebastian Inlet in Florida. Lake Okeechobee has also been placed into a hurricane warning.
A hurricane watch has also been issued north of Sebastian Inlet to the Flagler/Volusia county line in Florida. This includes Orlando, Florida.
Tropical storm warnings are now in effect from Chokoloskee to Golden Beach in Florida, for the Florida Keys from Seven Mile Bridge eastward, and for Florida Bay.
Hurricane warnings were expanded Tuesday morning to include the northwest Bahamas, including Nassau and Freeport. Hurricane warnings now include the entire Bahamas chain, as well as eastern Cuba and Haiti.

Current Watches/Warnings

Latest Status

Hurricane Matthew is moving northward as a strong and extremely dangerous Category 4 hurricane, with its eyewall moving off the northeast coast of Cuba.
(MORE: Guantanamo Bay, Cuba, Radar)

Current Storm Status
Matthew's tropical storm-force wind field (at least 39 mph sustained winds) extends up to 175 miles from the center, and hurricane-force winds extend up to 45 miles from the center.

Current Wind Speed and Gusts

Peak Impact Timing

Some fluctuations in intensity are possible over the next couple of days, but Matthew will likely remain a powerful hurricane into late week.
Here is the approximate timing of the worst wind and surge impacts, coinciding with the nearest passage of the eyewall of Matthew.

Projected Path and Intensity
  • Eastern Cuba: Into Wednesday morning
  • Southeast & central Bahamas: Through early Thursday
  • Northwest Bahamas: Wednesday night through Thursday night
  • Southeastern/Eastern Florida: Late Thursday through early Friday
  • Northeastern Florida: Early Friday through Friday evening
Small, subtle changes in the path of the eyewall, sometimes not resolvable until hours before the passage, can make a large difference on wind impact.
Note that even though certain locations may not be in the cone of uncertainty, impacts will be spread well beyond the edge of the cone.
(MORE: Facts/Myths About the Hurricane Cones of Uncertainty)

Caribbean Impacts

Impacts are beginning to wane in HispaƱola (including Haiti), but mudslides may continue for days.
Eastern Cuba is likely seeing its worst conditions through Tuesday night, and conditions will begin to improve on Wednesday morning.
A turn toward the north-northwest into the Bahamas is expected on Wednesday.
(NEWS: Latest Caribbean Impacts)
Over a foot of rainfall from Matthew will trigger life-threatening flash floods and mudslides. In Haiti, in particular, heavy rainfall could be catastrophic. Here are the latest rainfall projections from the National Hurricane Center:
  • Southern Haiti, southwest Dominican Republic: 15 to 25 inches, locally up to 40 inches
  • Northwestern Haiti, eastern Cuba: 8 to 12 inches, locally up to 20 inches
  • Eastern Jamaica: 4 to 6 inches, locally up to 12 inches
  • The Bahamas: 8 to 12 inches, locally up to 15 inches
  • Turks and Caicos: 2 to 5 inches, locally up to 8 inches
  • Northeast Haiti, rest of the Dominican Republic: 1 to 3 inches, locally up to 5 inches
  • Western Jamaica: 1 to 2 inches, locally up to 3 inches
  • Upper Florida Keys and much of the Florida East Coast: 4 to 7 inches, locally up to 10 inches
  • Middle to Lower Florida Keys: 1 to 3 inches, locally up to 5 inches
(MORE: Haiti's Deadly Hurricane History)

Forecast Rainfall
On the current forecast track, here are the latest storm surge forecasts from the NHC, above normal tide levels:
  • The Bahamas: 10 to 15 feet
  • South coast of Cuba east of Cabo Cruz: 7 to 11 feet
  • South coast of Haiti: 7 to 10 feet
  • North coast of Cuba east of Camaguey: 4 to 6 feet
  • Gulf of Gonave (Haiti): 3 to 5 feet
  • Florida east coast from North Palm Beach to the Volusia/Brevard County Line: 3 to 5 feet
It's worth noting this forecast for the Bahamas is on the order of storm surge witnessed during Hurricane Joaquin almost exactly one year ago, only for, potentially, the entire chain, rather than just the central and southeast Bahamas.
(FLASHBACK: Hurricane Joaquin 2015)
Battering waves will ride atop the storm surge, and coastal flooding from large waves may begin well in advance and ahead of Matthew's center.
This storm surge will also limit rainfall runoff in some places, aggravating flooding, especially in coastal locations where swollen rivers cannot drain.
Hurricane-force winds, with peak timing as outlined above, will lead to widespread structural damage, particularly to poorly-built structures, numerous downed trees and widespread power outages. Due to wet ground, trees will be even more susceptible to being toppled.
One possible analog to Matthew is Hurricane Hazel, which swept through Haiti in October 1954, claiming 400-1,000 lives from severe flash flooding and landslides.

U.S. Threat

Forecast guidance began to trend Monday toward a closer pass of Matthew to the Southeast coast, from Florida to North Carolina. This trend continued into Tuesday.
The reason for this is stronger high pressure aloft persisting over the western Atlantic and East Coast of the U.S., helping to trap Matthew closer to the coast.
(NEWS: Southeast U.S. on Alert)
Upper-level steering factors in play for Matthew later this week.
(MORE: Hurricane Central | Interactive Storm Tracker Map)
As far as timing for any potential impacts along the Southeast coast, here is a general overview. The National Hurricane Center forecast calls for Matthew to be a strong hurricane during this timeframe.
Florida Peninsula (particularly east): Thursday-Friday, possibly lingering into early Saturday in northeast Florida.
Southeast Georgia: Friday-Saturday.
Carolinas: Later Friday-Saturday, possibly continuing in eastern North Carolina into early Sunday.
The severity of any direct impacts (particularly from wind) will depend on how close the center of Matthew moves near the southeastern states.
Uncertainty is best summarized by the 5 p.m. Tuesday forecast from the National Hurricane Center:
When a hurricane is forecast to take a track roughly parallel to a coastline, as Matthew is forecast to do from Florida through South Carolina, it becomes very difficult to estimate impacts this far in advance.  For example, only a small deviation of the track to the left of the NHC forecast could bring the core of a major hurricane onshore, while a small deviation to the right could keep all of the hurricane-force winds offshore.  It will likely take another day or so for the potential impacts of Matthew in the United States to clarify.
The eyewall of Matthew could get close enough to shore that hurricane-force winds could come ashore on the Florida East Coast. That is becoming an increasing possibility from eastern Florida to the Carolinas.

Hurricane Force Wind Probabilities
In addition, storm surge flooding and rainfall flooding will also be threats in at least parts of these areas, depending on the exact track of Matthew. The current forecast for storm surge inundation from North Palm Beach to the Flagler/Volusia county line is 3 to 5 feet. Waves will enhance water damage along the coast.
Matthew will then accelerate northeast this weekend. While, again, the exact path will determine impacts, at least a chance of tropical storm-force winds and heavy rain is in play up the mid-Atlantic and New England coast, eventually into Nova Scotia or New Brunswick, Canada.
All interests along the U.S. East Coast and Atlantic Canada should monitor the progress of Matthew closely. Now is a good time to make sure you're prepared before the storm. Are you #HurricaneStrong?
Check back with us frequently at weather.com for any important forecast updates.

Storm Reports, Recap

George F.L. Charles Airport on St. Lucia picked up 9.21 inches of rain Wednesday. On the south side of the island, Hewanorra Int'l Airport picked up 13.19 inches of rain in just 12 hours from 8 p.m. Wednesday through 8 a.m. Thursday, according to the Antigua Met Service.
A wind gust to 89 mph was reported in St. Pierre, Martinique, Wednesday evening. Some stations are elevated at 50 to 100 feet. Sustained winds of 39 mph were reported on the island of Barbados.
Matthew strengthened to a rare Category 5 late Friday evening, becoming the first Category 5 Atlantic basin hurricane since Hurricane Felix in early September 2007.
(MORE: Category 5 Hurricanes Prior to Matthew)
Hurricane Matthew became the fifth hurricane of the 2016 Atlantic hurricane season early Thursday afternoon.
According to Colorado State University tropical scientist Dr. Phil Klotzbach, Matthew became the lowest latitude Category 5 hurricane in the Atlantic on record (beating the old record set by Ivan in 2004).
Some outer rainbands triggered flash flooding in Jamaica Sunday, hundreds of miles away from the center of Matthew.
Interestingly Sunday night, a fortunately-placed NOAA buoy sampled Matthew's eye, providing valuable information for meteorologists.
Hurricane Matthew's eye first came ashore in the Greater Antilles in the western Tiburon Peninsula of Haiti near the town of Les Anglais around 7 a.m. EDT Tuesday morning, according to the National Hurricane Center.
Matthew was the first Category 4 Haiti landfall since Hurricane Cleo in 1964, and only the fourth such intensity or stronger hurricane to track within 65 nautical miles of southern Haiti's Tiburon Peninsula since the 1960s, according to NOAA's Best Tracks Database.

No comments:

Post a Comment