Category: Tropical Weather

Tropical Storm Henri has made the long-awaited northerly turn and now is heading towards New England or Long Island.

As of 11pm Friday, Tropical Storm Henri was centered about 615 miles south of Montauk, New York, moving toward the north at 9 mph. Maximum sustained winds were near 70 mph. Henri is expected to strengthen for the next 24 hours or so as wind shear begins to lessen and the storm remains over the warm waters of the Gulf Stream. Henri will likely become a hurricane on Saturday.

With a ridge of high pressure building in to the east of Henri, and an upper-level low pressure area developing over the Great Lakes, Henri will be steered northward for the next 24 hours, Beyond that, the upper-level low will start pull Henri northwestward and slow it down as it begins to approach Long Island or Southern New England. Since it will be over cooler water at that time, it will begin to weaken. Current forecasts show that Henri may still be a minimal hurricane at landfall, but there is also a good chance that it may weaken to a tropical storm by the time it reaches land.

Although the exact track and intensity are still in question, the general impacts should be similar to most tropical systems that impact the Northeast. These systems tend to become lopsided, with the strongest winds mainly to the right of the center, and most of the rain shifting to the left of the track. The current forecast of a track towards eastern Long Island would mean that gusty winds and the highest storm surge would impact parts of Rhode Island and southeastern Massachusetts, including Cape Cod. The storm surge will be compounded by the fact that with a full moon on Sunday, tides will be astronomically high, exacerbating any storm surge flooding. The western track would also mean that the heaviest rain and greatest threat of freshwater flooding, would shift to Long Island, western portions of Connecticut and Massachusetts, and eastern New York.

While the winds won’t be particularly strong across much of Southern New England, tree damage could be more extensive that you’d normally expect. It has been a very wet summer across the region, with many places receiving 10-20 inches since the beginning of July. As a result, the ground is saturated across much of the area, so it won’t take strong winds to knock trees over. It also will result in more extensive flooding in areas that receive heavy rain.

As the steering currents weaken late Sunday and Sunday night, Henri or what’s left of it, may stall out across western New England or eastern New York, then eventually start moving eastward, bringing more rain to parts of central and northern New England. Conditions will improve from west to east on Monday as the storm departs and high pressure starts to build into the region.

As we get into the middle of August, there are now three active systems in the Atlantic and two more in the Pacific, and all but one are a threat to land.

The most immediate threat is Tropical Storm Fred. After sputtering over Cuba this past weekend, Fred emerged into the eastern Gulf of Mexico and has become better organized. As of early Monday afternoon, Fred was centered about 35 miles southwest of Apalachicola, Florida, moving toward the north at 10 mph. Maximum sustained winds have increased to 65 mph. Tropical Storm Warnings and Storm Surge Warnings are in effect for parts of the Florida Gulf Coast. Fred may strengthen a little more before it makes landfall late this afternoon. Once inland, it should rapidly weaken. The main threats from Fred are strong winds, heavy rain, and storm surge, along with the possibility of a few tornadoes.

Fred will produce 4-8 inches of rain across parts of Florida and southern Georgia, with some locally heavier amounts. As it moves inland and weakens, the moisture will start to interact with a frontal system, bringing heavy rain to parts of the Southeast, Mid-Atlantic States, and the Appalachians. In these areas, rainfall totals of 3-6 inches and locally heavier will likely lead to flooding over the next few days.

While Fred heads for Florida, Grace may be starting to get its act together near Haiti Grace brought heavy rain to parts of the northeastern Caribbean this weekend, but was very poorly organized. It looks a bit healthier this afternoon as it nears the south coast of Haiti. It was centered about 70 miles southeast of Port-au-Prince, Haiti early Monday afternoon, moving toward the west-northwest at 12 mph. It is still a tropical depression with maximum sustained winds near 35 mph. A Tropical Storm Warning is in effect for parts of southern Cuba and the Cayman Islands, while Tropical Storm Watches are in effect for Haiti, Jamaica, and parts of southern Cuba.

Grace is expected to continue on a general west to west-northwest course for the next few days. As it pulls away from Haiti late tonight, it should move over the warm waters of the northwestern Caribbean south of Cuba, and gradual strengthening is expected. The current forecast calls for it to be a strong tropical storm as it approaches the northern Yucatan Peninsula by the middle of the week. Beyond that, a track into the Gulf of Mexico seems likely at this point.

Out in the central Atlantic, Tropical Depression Eight developed late Sunday night. As of early Monday afternoon, it was centered about 140 miles southeast of Bermuda, moving toward the south at 9 mph. Max sustained winds were near 35 mph. A Tropical Storm Watch is in effect for Bermuda. The system is expected to become a tropical storm later today or tonight as it turns westward and rides around a ridge of high pressure. Eventually, it will turn back to the north and northeast and head out into the open Atlantic. There is a slight chance that it could impact the East Coast, depending on how quickly it makes the turn. It should bring some rough seas to the coastal waters from the Carolinas to New England later this week.

In the Eastern Pacific, Hurricane Linda still has maximum sustained winds near 105 mph at midday. It was centered about 955 miles west-southwest of Cabo San Lucas, Mexico, and moving toward the west-southwest at 9 mph. Linda reached Category 4 strength over the weekend, but now is gradually weakening over open water. It should continue on a general west to west-northwest track this week while slowly weakening. It should pass well north and east of Hawaii late this week as a weakening extratropical system, with little impact other than some rough surf.

In the Western Pacific Ocean, Tropical Depression 16W remains fairly weak. It only has maximum sustained winds near 25 mph, and is centered about 180 miles east of Guam, moving toward the west at 18 mph. It will bring heavy rain and some gusty winds to the Northern Mariana Islands over the next 24 hours as it passes very close to Guam.

The system may start to strengthen once it gets past the Northern Marianas and turns a bit more toward the northwest. Some forecasts call for it to become a tropical storm, and possibly a typhoon by the end of the week. Where it will go is highly uncertain at this point. While the official forecast from the Joint Typhoon Warning Center has it heading towards Taiwan, various models have it continuing westward to the Philippines, continuing west-northwestward toward Taiwan and/or eastern China, or turning northward and heading toward Japan. It will have to be watched closely later this week.

The tropical disturbance that brought heavy rain to parts of the Lesser Antilles, Virgin Islands, and Puerto Rico over the past few days developed into Tropical Storm Fred late Tuesday night.

As of early Wednesday afternoon, Tropical Storm Fred was centered about 30 miles west of Santo Domingo, Dominican Republic, moving toward the west-northwest at 16 mph. Maximum sustained winds were near 45 mph, but some weakening is likely over the next 12-24 hours with the center over land. A Tropical Storm Warning remains in effect for much of the Dominican Republic, with Tropical Storm Watches in effect for parts of Haiti, eastern Cuba, the Turks and Caicos Islands, and the southeastern Bahamas.

The combination of the center crossing the mountainous terrain of Hispaniola and westerly wind shear will keep Fred weak for the next day or two as it heads west-northwestward across Haiti and close to the coast of Cuba. Whether the center stays offshore of Cuba or near or just onshore will have an impact on how much the storm starts to re-strengthen. It will produce gusty winds and heavy rain across Hispaniola, eastern Cuba and parts of the Bahamas, leading to flooding and mudslides. Rainfall totals of 3-6 inches and locally heavier are likely across these areas.

By late Friday or early Saturday, Fred will start to turn more toward the northwest as it rounds the edge of a large ridge of high pressure over the Atlantic. This should bring the storm across the Florida Keys early Saturday, and then into the eastern Gulf of Mexico. It should start to strengthen again over the warm waters of the Gulf as it heads toward the northern Gulf Coast. The current forecast from the National Hurricane Center calls for Fred to make landfall in the Florida Panhandle early Monday as a strong tropical storm. However, given the average errors in a typical forecast for a tropical system, it wouldn’t be a surprise if Fred was a hurricane by then. Landfall could also take place as far west as Louisiana if the northerly turn takes place a little later, or the system could turn earlier and impact southern or even southeastern Florida. A lot of these variables should become a bit clearer once Fred emerges from Hispaniola early Thursday. It does seem likely that heavy rain will impact at least parts of southern Florida this weekend, with flooding likely. Tropical Storm Watches will likely be issued for at least the Florida Keys, if not parts of southern Florida as well, late tonight or early Thursday.

Fred is the only named storm in the Atlantic right, but there’s a tropical wave several hundred miles west-southwest of the Cabo Verde Islands that bears watching. That wave will make its way across the Atlantic over the next several days. It is disorganized at the moment, but conditions should become more favorable for development over the next few days. Some models show to potential for it to become a tropical depression as it nears the Lesser Antilles this weekend. This wave will be monitored closely over the next few days as it continues its trek westward.

The Atlantic isn’t the only active basin at the moment. In the Eastern Pacific, Tropical Storm Kevin is a few hundred miles west-southwest of Baja California, but it is expected to dissipate over open water in the next few days. There is also Tropical Storm Linda, located a few hundred miles off the southwest coast of Mexico. Linda is expected to become a hurricane tonight or Thursday, but will head west-northwestward away from land for the next several days. In the Western Pacific, Tropical Depression 16W is located just west of the International Dateline, but should remain fairly weak as it heads westward over the next few days. It could impact a few islands, such as Enewetak, with squally conditions over the next few days, but in general, it isn’t much of a threat.

Less than 48 hours after it formed east of the Lesser Antilles, Hurricane Elsa is now racing across the eastern Caribbean.

As of 2am Saturday, Hurricane Elsa was centered approximately 620 miles east-southeast of Kingston, Jamaica, moving toward the west-northwest at 29 mph. Maximum sustained winds are near 80 mph.

Hurricane Warnings are in effect for southern portions of the Dominican Republic and Haiti, as well as for the island of Jamaica, with Tropical Storm Warnings for the remainder of the Dominican Republic and Haiti. A Hurricane Watch is in effect for parts of eastern Cuba, and a Tropical Storm Watch is in effect for parts of the Cayman Islands.

Elsa could strengthen a bit on Saturday, but for the most part, weakening is forecast. Some dry air got entrained in the circulation late Friday, okus the current rapid forward speed with both serve to inhibit any further strengthening, Although Elsa is expected to slow down over the next 24 hours, a turn more toward the northwest is expected. This will bring the storm closer to Hispaniola, where the mountainous terrain could disrupt the circulation as well.

Current forecasts bring the center of the storm close to southern Haiti Saturday night, then toward southeastern and southern Cuba on Sunday. The intensity of the storm will be determined partially by the track the storm takes. The longer the circulation center stays over water, the better chance that the storm is stronger.

As the storm slows down, it increases the chances for heavy rainfall across southern portions of Hispaniola, eastern and southern Cuba, and parts of Jamaica. Rainfall totals of 6-12 inches and locally heavier will lead to flooding and mudslides.

Elsa is expected to cross Cuba on Monday while turning northward. Given that this is already three days out, the uncertainty in the forecast becomes much large. A track towards Florida seems likely, but is far from definite at this point. Several models bring the storm up the west coast of Florida, while many others bring it up the east coast or even over the Bahamas. How strong the storm is at this point is also highly uncertain. Residents from the central Gulf Coast all the way to the Carolinas should keep tabs on the system this weekend, as it has the potential to impact anywhere within that range by the early to middle portion of next week.

As Elsa crossed the Windward Islands on Friday, it produced wind gusts as high as 86 mph on Barbados and 79 mph on Saint Lucia, making it the first hurricane of the 2021 season. This is the earliest in the season that a storm has hit Barbados, and it is the 2nd earliest Hurricane ever in the eastern Caribbean, trailing only an unnamed storm from 1933.

We’re only two weeks into Hurricane Season, and the peak of the season is still three months away, but activity is starting to ramp up in the Atlantic.

Tropical Depression Two developed off the North Carolina coast on Monday. As of 11pm Monday, it had strengthened into Tropical Storm Bill, and was centered about 335 miles east-northeast of Cape Hatteras, NC, moving toward the northeast at 23 mph. Maximum sustained winds were near 45 mph. The system remains weak, and there is not a lot of thunderstorm activity with it at the moment, but it is moving over the warm waters of the Gulf Stream, so there is a small window for the system to intensify over the next 12-18 hours. After that, it will be moving over colder water, and will weaken before bringing some gusty winds and rainfall to parts of Newfoundland and possibly Nova Scotia later this week.

In the eastern Atlantic, a strong tropical wave has moved off the west coast of Africa, passing south of the Cabo Verde Islands tonight. While this system may develop a little over the next day or two, the combination of unfavorable upper-level winds and dry air will limit any development once the system reaches the central Atlantic Ocean. Once we get a little deeper into hurricane season, conditions should become more favorable as more and more waves roll off of Africa and cross the Atlantic. Some of these storms historically have become powerful systems, as they have plenty of time to develop over open water.

In the Bay of Campeche, a cluster of showers and thunderstorms continues to meander around associated with a broad area of low pressure. While this will produce some heavy rain across parts of Mexico and Central America, it is not expected to develop over the next few days. By late in the week, the system will start drifting northward, and conditions will become more favorable for development. It could become a tropical depression by the weekend, then it may head toward Louisiana or Texas.

While it’s still a little early to speculate on any potential track or strength for this system, most of the models are in agreement that most of the rain from this system will head towards Louisiana. Much of southern Louisiana and Mississippi has received 30 to 45 inches of rain over the past 90 days, which is more than twice the normal amount they receive in that time frame. This has led to widespread flooding in areas still attempting to recover from several direct hits during the 2020 hurricane season. A tropical system, even a weak one, could drop 10 or more inches of rain on this area, leading to even more flooding.

Elsewhere, the only other active system in the tropics is Tropical Depression Carlos in the Eastern Pacific, but it is expected to dissipate on Tuesday over open water.