Hurricane Florence

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It should be noted that there is considerable model ensemble spread
and run-to-run variability for Florence's track beyond day 5. Given
the large uncertainty at these time ranges, it is far too soon to
speculate what, if any, impacts Florence may have on the U.S. East
Coast next week. Regardless of Florence's eventual track, large
swells emanating from the hurricane will reach Bermuda beginning on
Friday, resulting in life-threatening surf and rip currents on the
island. Swells from Florence could also reach the U.S. East Coast by
early next week.

TROPICAL UPDATE for FRIDAY: Concern is increasing that FLORENCE is going to impact the east coast of the U.S. The likelihood of a significant landfalling hurricane is increasing, although a track where the storm sideswipes the coast is still certainly a possibility. There is also a chance the storm will stay far enough offshore to have minimal impact, although the likelihood of that path appears to be diminishing.

In addition, two systems near Africa are on the cusp of being named HELENE and ISAAC respectively. More on them below.

FLORENCE is a 65-mph tropical storm this morning. Hostile upper level winds have weakened it, but are forecast to let up tomorrow. Once the storm gets through this rough patch, unfortunately a number of factors will line up that should allow Florence to dramatically re-strengthen. The upper-level environment is forecast to be extremely conducive for strengthening, and the ocean temperature beneath the storm will become quite warm, providing more than enough fuel for a strong hurricane.

Florence’s track is extraordinarily unusual. Never in the record book has a storm located where Florence is now impacted the east coast of the U.S. But, the high-pressure system, under which Florence will be trapped, is much stronger than normal as well. Its circulation will drive Florence in the direction of the East Coast.

Think of the high-pressure system as an elongated bubble of air. Florence will drive along the south side of that bubble. The question is, where is the back side, the west side of the bubble, when Florence gets near the coast. A dip in the jet stream will be coming along to erode the back side of the high and provide a path north for Florence. The big unknown is precisely where and how the path north will evolve.

We understand the broad strokes, but the details count, and will make the difference between a landfall in the Carolinas, a track up the Mid-Atlantic coast, or an early turn keeping the storm offshore – or many other possibilities. It is simply too early to know.

Expect Florence to be strengthening over the weekend, and approaching the coast about next Wednesday. On the current schedule, hurricane preparations would need to be completed by then.

The primary potential threat areas at the current time are from the Carolinas to Long Island, New York. It’s not impossible that the Georgia coast could be affected as well. Everybody in this zone should know what they would do if Florence becomes a direct threat to their area next week.

HELENE-to-be: The system that is likely to develop into Tropical Storm Helene in the next few days is about 3,000 miles southeast of Miami. The system is moving west toward the Caribbean. It should arrive in the vicinity of the Lesser Antilles next Wednesday or Thursday. All interests in the Caribbean Islands should stay informed about the progress of this system. We will keep a watchful eye in Florida as well to be sure the system stays south.

ISAAC-to-be: A relatively short way behind Helene-to-be is a system that will likely be named ISAAC in the next few days. It is a threat to the Cabo Verde Islands, but after that it appears most likely to turn out to sea. We will watch closely to be sure it does.

8:00 AM ET TROPICAL UPDATE for SATURDAY: There is no good news on FLORENCE this morning. The system is beginning the reorganization and restrengthening process – the estimated peak winds are now 65 mph. The hostile upper-level winds appear to be relenting on schedule – and the storm is heading toward pristine atmospheric conditions over deep warm water.

THE EXPECTATION IS THAT A POWERFUL HURRICANE WILL APPROACH THE MID EAST COAST OF THE U.S. NEXT WEDNESDAY OR THURSDAY.

In the far east Atlantic, TROPICAL DEPRESSION #9 will soon be named ISAAC. It is also expected to intensify into a hurricane. It is forecast to move due west and is scheduled to reach the Caribbean Islands, possibly including those ravaged last year, on Wednesday or Thursday as well.

TROPICAL STORM HELEN is only of concern to the Capo Verde Islands near Africa. After passing those islands, it is expected to turn out to sea. MORE ON ISAAC AND HELENE BELOW.

FLORENCE: The forecast for the next 5 days appears straightforward. An unusually strong, elongated high pressure cell (a huge bubble of air) will build across the North Atlantic to the north of Florence. This will accelerate the hurricane toward the middle U.S. East Coast. Every indication is Florence will strengthen into a very powerful hurricane during this time.

That takes us to early late Wednesday or early Thursday with Hurricane Florence bearing down – Georgia or the Carolinas appear to be the target zone at this point, but Virginia, the Delmarva Peninsula, and South Jersey are on the side of the storm with the strongest winds and highest storm surge so some action may well be required there as well, depending on the final path.

At this point thing get murky. There are several possibilities.

It appears that Florence will slow down as it turns around the west end of the bubble of high pressure. That would cause the hurricane, or what’s left of it if it moves inland, to slowly exit to the north. That process could take some days causing serious inland and coastal flooding, as well as other hazards.

The bottom line is that everybody from Georgia through the Carolinas to Virginia, at the coast and in the eastern part of those states including WASHINGTON, DC and nearby cities, should be sure they are ready for extended power outages and dangerous weather conditions, which in some cases will require evacuations.

The storm has the potential to eventually affect every state in the Mid-Atlantic and Northeast in one fashion or the other. STAY IN TOUCH WITH YOUR LOCAL AUTHORITIES.

North Florida is likely out of the immediate danger zone, but it’s a good time to be sure your hurricane plan is in order just in case.

ELSEWHERE, a system designated DISTURBANCE #94L is located near Bermuda. It is very disorganized, and will likely be absorbed into the jet stream before it can attain a circulation. Assuming that happens, it will be of no consequence to Florence. The National Hurricane Center gives it only a 10% chance of organizing into at least a Tropical Depression. For now, we’ll ignore it as a factor in the forecast for Florence.

TROPICAL DEPRESSION #9, soon to be TROPICAL STORM ISAAC, is looking more organized this morning and will soon reach tropical-storm strength. It appears the high pressure filling in behind Florence will extend far enough south to block this system from turning north. The atmospheric conditions do not appear ideal for rapid strengthening, but we often do not have a handle on all of those factors. The bottom line, people in the eastern Caribbean Islands need to be ready for a hurricane arriving mid to late next week.

After the storm passes though or near the islands, the path and strength become uncertain. For now, in Florida we will watch how things develop in the next few days. It is still almost 3,000 miles away from Miami.

TROPICAL STORM HELENE will pass through the Cabo Verde Islands tonight and tomorrow, then turn out to sea. It is expected to reach hurricane strength, but not be a threat to the U.S.

5:00 PM ET TROPICAL UPDATE for SATURDAY: The news continues to be ominous about FLORENCE. The system is reorganizing and restrengthening. The estimated peak winds are now 70 mph, just below hurricane strength. The hostile upper-level winds are relenting on schedule – and the storm is heading toward much more favorable atmospheric conditions over deep warm water. Florence will likely be a hurricane soon.

THE EXPECTATION REMAINS THAT A POWERFUL HURRICANE WILL APPROACH THE SOUTHEAST OR MID-ATLANTIC COAST NEXT WEDNESDAY OR THURSDAY.

The forecast for the next 5 days appears straightforward. An unusually strong, elongated high pressure cell (a huge bubble of air) will build across the Northeast into the North Atlantic to the north of Florence. This will accelerate the hurricane in the direction of the Southeast or southern Mid-Atlantic coast. Every indication is Florence will strengthen into a very powerful hurricane during this time.

That takes us to late Wednesday or early Thursday with Hurricane Florence bearing down on the coast – the Carolinas appear to be the target zone at this point, but Georgia, Virginia, and the Delmarva Peninsula need to maintain vigilance as well since the forecast gets difficult in about 5 days.

Once the storm is off the coast on Wednesday, the steering currents get murky. There are several possibilities.

It appears that Florence will slow down as it turns around the west end of the bubble of high pressure. That would cause the hurricane, or what’s left of it if it moves inland, to slow down. That process could take some days causing serious inland and coastal flooding, as well as other hazards.

It is also possible that the storm will stall toward the end of the week and meander. Or perhaps move slowly north or northeast. The point is, the approach to the coast is just Phase One of this event. There may well be a Phase Two and Phase Three as a slow-moving weaker storm drifts around.

The bottom line is that everybody from Georgia through the Carolinas to Virginia, at the coast and in the eastern part of those states including Washington, DC and nearby cities, should be sure they are ready for extended power outages and dangerous weather conditions, which in some cases will require evacuations. Vigilance is required as far north as Long Island, New York due to the uncertainty in the track late next week.

Remember the rule, slow-moving storms are notoriously difficult to forecast. It appears that Florence will fall into that category once it gets near or across the coastline.

if the high pressure area remains strong, then Florence may complete a 3,500-mile-long journey over the Atlantic and be guided right into the U.S. East Coast somewhere from the Carolinas to southern New England sometime during the second half of the week.

AccuWeather meteorologists are favoring this latter solution, which will bring more severe impacts to the U.S. East Coast.

The evidence points to Hurricane Florence becoming very strong and making a beeline for the Southeast coast. South and North Carolina are the current target zone, with significant effects possible in Georgia to the south, and in Virginia and the Delmarva peninsula just to the north, depending on the exact landfall point.

Initial hurricane preparations should already be underway in the target areas.

The big question mark is what’s going to happen as Florence approaches the coast late on Wednesday or on Thursday. The steering currents from the unusually strong bubble of high pressure pushing Florence toward the U.S. will collapse as the bubble moves away.

It appears that Florence will be abandoned to meander or move slowly at the end of the week and over next weekend.

The current model consensus is that Florence will make landfall and stall inland, but it is not impossible that the stall comes very near the coast. In either case, a devastating coastal battering combined with a hugely dangerous inland flood event appears to be the most likely outcome.

The possibility of Florence turning north as a strong hurricane appears remote. The storm may combine with an approaching cold front AFTER NEXT WEEKEND to cause problems north into the Mid-Atlantic states, but it is too early to know exactly how those systems are going to interact, if they do.

8:00 AM TUESDAY TROPICAL UPDATE: A Hurricane and Storm Surge Watch has been issued for most of the South Carolina coast and all of the North Carolina coast.

Summary: HURRICANE FLORENCE may reach Category 5 strength today as it makes a beeline for the Carolinas. ISAAC is struggling to maintain its strength, but is on track toward the Caribbean at or near hurricane strength. In addition, a disturbance in the western Caribbean is heading for the western Gulf where it may develop into a threat for Texas or Northern Mexico.

FLORENCE is still a Category 4 hurricane, though it is going through an internal process called an “eyewall replacement cycle” whereby it weakens temporarily, expands into a bigger hurricane, and then restrengthens. The current peak winds are estimated at 130 mph – Category 4. It has warmer ocean water and optimal atmospheric conditions ahead of it, which means more strengthening is likely.

The expectation is that it will strengthen some more before it approaches the Carolina coast on Thursday. Strong hurricanes always fluctuate in intensity, so it is impossible to know if might hit the coast at full strength, but the expectation is that it will be an extremely strong and destructive hurricane. In addition, Florence is expected to expand in size over the next two days. Widespread coastal destruction is expected to be Phase One of this disaster

The steering currents are well established for now, so there is high confidence that Florence will reach the North or South Carolina coast on Thursday. About that time, the steering currents will collapse, however, so for at least a couple of days, the hurricane, or a weaker version of the storm, will meander and dump rain. This might happen close to the coast, or well inland. Phase Two of this disaster will be caused by the slow-moving storm. It will either continuously batter the coast, severely flood inland areas, or more likely, both.

Bear in mind that slow-moving storms are notoriously poorly forecast, so don’t count on any precise track forecasts during or after landfall. In addition, the damaging winds and flooding rain will occur far from the storm’s center, especially to the north, meaning the exact track is not important. Widespread rainfall of 15-20 inches with up to 30 inches in some locations is possible. This part of the eastern U.S. has been saturated by rain this year, so extreme flooding is possible.

Here are the Key Messages from the National Hurricane Center concerning Florence:

1. A life-threatening storm surge is likely along portions of the coastlines of South Carolina, North Carolina, and Virginia, and a Storm Surge Watch has been issued for a portion of this area. All interests from South Carolina into the mid-Atlantic region should ensure they have their hurricane plan in place and follow any advice given by local officials.

2. Life-threatening freshwater flooding is likely from a prolonged and exceptionally heavy rainfall event, which may extend inland over the Carolinas and Mid Atlantic for hundreds of miles as Florence is expected to slow down as it approaches the coast and moves inland.

3. Damaging hurricane-force winds are likely along portions of the coasts of South Carolina and North Carolina, and a Hurricane Watch has been issued for a part of this area. Damaging winds could also spread well inland into portions of the Carolinas and Virginia.

4. Large swells affecting Bermuda and portions of the U.S. East Coast will continue this week, resulting in life-threatening surf and rip currents.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* South Santee River South Carolina to Duck North Carolina
* Albemarle and Pamlico Sounds, including the Neuse and Pamlico
Rivers

A Storm Surge Watch is in effect for...
* Edisto Beach South Carolina to South Santee River South Carolina
* North of Duck North Carolina to the North Carolina/Virginia border

A Hurricane Warning is in effect for...
* South Santee River South Carolina to Duck North Carolina
* Albemarle and Pamlico Sounds

A Hurricane Watch is in effect for...
* Edisto Beach South Carolina to South Santee River South Carolina
* North of Duck North Carolina to the North Carolina/Virginia border

A Tropical Storm Watch is in effect for...
* North of the North Carolina/Virginia border to Cape Charles Light
Virginia
* Chesapeake Bay south of New Point Comfort

Interests elsewhere in the southeastern and mid-Atlantic states
should monitor the progress of Florence. Additional watches and
warnings may be required tonight or Wednesday.

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of tropical-storm-
force winds, conditions that make outside preparations difficult or
dangerous. Preparations to protect life and property should be
rushed to completion.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


HAZARDS AFFECTING LAND
----------------------
STORM SURGE: The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline. The water has the
potential to reach the following heights above ground if peak surge
occurs at the time of high tide...

Cape Fear to Cape Lookout, including the Neuse and Pamlico
Rivers...9-13 ft
North Myrtle Beach to Cape Fear...6-9 ft
Cape Lookout to Ocracoke Inlet...6-9 ft
South Santee River to North Myrtle Beach...4-6 ft
Ocracoke Inlet to North Carolina/Virginia Border...4-6 ft
Edisto Beach to South Santee River...2-4 ft

The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
destructive waves. Surge-related flooding depends on the relative
timing of the surge and the tidal cycle, and can vary greatly over
short distances. For information specific to your area, please see
products issued by your local National Weather Service forecast
office.

RAINFALL: Florence is expected to produce total rainfall
accumulations of 15 to 25 inches with isolated maximum amounts of
35 inches near the storm's track over portions of the Carolinas and
Mid-Atlantic States from late this week into early next week. This
rainfall would produce catastrophic flash flooding and significant
river flooding.

WIND: Hurricane conditions are expected to reach the coast within
the hurricane warning area on Friday. Winds are expected to first
reach tropical storm strength on Thursday, making outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

SURF: Swells generated by Florence are affecting Bermuda and
portions of the U.S. East Coast. These swells are likely to cause
life-threatening surf and rip current conditions. Please consult
products from your local weather office.

Hurricane Florence, with its strong winds and massive storm surge, threatens to release toxic chemicals from hazardous waste sites that the Environmental Protection Agency has designated contaminated Superfund sites. ...

The Superfund sites monitored by the EPA ahead of the hurricane and their potential risks include:

Macalloy Corp.
This Charleston, South Carolina, site of former smelting operations was found to contain cancer-linked chemicals.

Koppers Co. Inc.
This is a Charleston site of former lumber and fertilizer facilities near the Macalloy site. Underground contamination has been capped there.

Geiger
This site near Charleston processed waste oil, including in unlined lagoons, resulting in soil contamination. It is currently used for equipment storage for a construction firm.

Parris Island Marine Corps Recruit Depot
This military facility in Beaufort County, South Carolina, had a variety of former uses that contaminated water and soil, including dry cleaning, waste dumping and paint disposal. EPA information indicates the part previously used for pesticide storage poses the highest ongoing risks.

Wamchem Inc.
This site in Beaufort County has a former dye production facility that contaminated groundwater and soil. Groundwater treatment continues there.

Triangle Pacific Corp.
This site in Pasquotank County, North Carolina, was known to have generated two separate hazardous waste streams from the manufacturing of wooden cabinets. The waste streams were created from spent non-halogenated solvent-based toner, lacquer thinner and lacquer dust. The toner and lacquer thinner reportedly contained various chemicals, including methyl ethyl ketone, toluene, acetone and isobutanol as well as the metals cadmium and arsenic. The nearest residence is about 300 feet from the site.

Marine Corps Air Station Cherry Point
This 13,164-acre site in Havelock, North Carolina, includes an active Marine Corps installation. The site contains contaminated groundwater, soil, sediment and surface water resulting from the installation's operations.

Horton Iron and Metal
The 42-acre Horton Iron and Metal site is in Wilmington, North Carolina. Fertilizer manufacturing took place at the site from 1911 to 1954. The site contains contaminated soil, sediment and groundwater from past industrial operations there.

FCX Inc.
Located in Beaufort County, North Carolina, this is the site of a former farm-supply distribution center that contaminated ground and surface water and soil with pesticides, herbicides and chemicals used to treat tobacco.

6:00 PM TROPICAL UPDATE: HURRICANE FLORENCE is on course for the North and South Carolina coast. When it gets there, it is forecast to stall. It appears that the bizarre scenario of a meandering hurricane that will prolong the misery is now likely. The new forecast indicates that much of South Carolina and perhaps part of Georgia will eventually be impacted by the storm as well.

• HURRICANE FLORENCE is on track to be an historic disaster in the Carolinas extending at least through the weekend.

HURRICANE FLORENCE now has top winds estimated at 120 mph – Category 3. While the highest winds have come down a bit, the energy is spread out in a larger storm, which will increase the storm surge over more of the coast.

The track through tomorrow is unchanged. The weather will deteriorate on the North Carolina coast tomorrow, and the eye is expected to impact the coast on Friday. At that point the storm is expected to have slowed to a crawl, and to move south along or just offshore of the South Carolina coastline.

If the center says over the water, the hurricane will stay stronger longer, prolonging the hammering on the coastline.

Hurricane Warnings and Storm Surge Warnings are in effect for most of the South Carolina and all of the North Carolina coast. Storm surge will be life-threatening over the part of that coastline that ends up north of the storm center. The National Hurricane Center is forecasting the ocean water to be pushed 9-13 feet over the land on the Outer Banks of North Carolina, with lesser but still life-threatening surge over most of the Carolina coast and up into the various bays, rivers, and inlets.

In addition, the rainfall forecast has now increased to 20 to 30 inches for the coastal areas of the Carolinas, with some spots receiving 40 inches. Inland areas will receive less, but still 5-10 inches with some areas receiving 20 inches of rain. All that water will try to run out the rivers, streams, and inlets, while the storm surge is pushing in from the ocean. It is a recipe for a disastrous flood, on top of the damage from the wind.

A hurricane that stalls and meanders is one of the most destructive scenarios.

Here are the Key Messages from the National Hurricane Center concerning Hurricane Florence:

1. A life-threatening storm surge is now highly likely along portions of the coastlines of South Carolina and North Carolina, and a Storm Surge Warning is in effect for a portion of this area. All interests in these areas should complete preparations and follow any advice given by local officials.

2. Life-threatening, catastrophic flash flooding and prolonged significant river flooding are likely over portions of the Carolinas and the southern and central Appalachians late this week into early next week, as Florence is expected to slow down as it approaches the coast and moves inland.

3. Damaging hurricane-force winds are likely along portions of the coasts of South Carolina and North Carolina, and a Hurricane Warning is in effect. Strong winds could also spread inland into portions of the Carolinas.

4. Large swells affecting Bermuda, portions of the U.S. East Coast, and the northwestern and central Bahamas will continue this week, resulting in life-threatening surf and rip currents.

HURRICANE FLORENCE begins its assault on the North Carolina coast today. Top winds have decreased to 110 mph – Category 2, but the strong winds have also spread out, which will result in a huge strong surge over a larger area. Recall that Hurricane Ike was a similar Category 2 when it came ashore near Houston 10 years ago, with catastrophic results in unprotected coastal communities.

The center is now less than 200 miles from North Carolina. Gusty squalls are already impacting the coast.

The winds from HURRICANE FLORENCE will pick up on the North Carolina coast today, but the forward motion of the storm will also continue to slow down, so it will take until tomorrow until the highest winds will be blowing, and the peak storm surge – the ocean water pushed up over the land – comes in.

When the center of Florence gets near the coast or just across the North Carolina coastline, it will turn to the left and head toward South Carolina. The open question is whether it ever makes landfall in North Carolina, or whether it just comes close and badly batters the coast with wind and storm surge, and then heads south with the center over the ocean.

If it crossed the coast and heads south inland, there will be more flooding of inland sections. If the center stays offshore, the storm surge will be higher over more of the coast, and the highest rain totals will occur less far inland. Even at this late hour, we can’t be sure which will occur.