Hurricane Season 2017 #1: The year after El Nino

Severe Weather Update: Tropical cyclone Blanche, 6 March 2017

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Cyclone Blanche aims for Western Australia
Tropical Cyclone "Blanche" formed late March 5, 2017 in the Timor Sea and soon crossed the Kimberly coast between Wyndham and Kalamburu, Western Australia as Category 2 system on the Australian tropical cyclone intensity scale. This is the equivalent of a Category 1 hurricane on the Saffir-Simpson hurricane wind scale.

As the cyclone formed and strengthened, Bathurst Island recorded 384 mm (15.1 inches), which has smashed the previous daily rainfall total by more than 100 mm (3.9 inches).

Blanche had sustained winds near the center of 95 km/h (59 mph) with wind gusts to 130 km/h (81 mph), the Australian Bureau of Meteorology said at 02:00 UTC today (12:30 ACST). It was moving southwest at 18 km/h (11 mph).

The agency said destructive winds with gusts to 150 km/h (93 mph) are being experienced between Kalumburu and Wyndham in WA, easing to gales this afternoon (local time) as the system weakens.

Gales with gusts to 120 km/h (74 mph) are also being experienced between Wyndham and Kalumburu in WA, easing during this evening to below gale force.

Tides will be higher than normal between Wyndham and Kalumburu in WA during today. Large waves may produce minor flooding of low-lying coastal areas.

A Yellow Alert is in effect between Wyndham and Kalumburu and coastal communities, people need to take action and get ready to shelter from a cyclone.

Blue Alert is in effect between WA/NT Border to Kununurra and people need to prepare for cyclonic weather and organize an emergency kit including first aid kit, torch, portable radio, spare batteries, food and water.

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Enawo made landfall as category 4 : Third strongest ever to hit Madagascar
Intense Tropical Cyclone "Enawo" made landfall between Sambava and Antalaha, Madagascar on March 7, 2017, as Category 4 hurricane equivalent on the Saffir-Simpson scale. It is the most powerful tropical cyclone to hit Madagascar since Gafilo in March 2004 and the third strongest on record to strike the island. Enawo is predicted to affect approximately 1.4 million people. Another tropical cyclone is brewing to the east of the country and will likely be named over the next 24 hours.

Enawo made landfall at 08:00 UTC (11:00 local time) on March 7 at 14.6 degrees north latitude and 50.2 degrees east longitude, about half way between Sambava and Antalaha. As it hit, Enawo became quasi-stationary and pounded Antalaha with strong winds and heavy rain for several hours.

At 09:00 UTC (4 a.m. EST) its maximum sustained winds were 231 km/h (144 mph) making it a Category 4 hurricane on the Saffir-Simpson Wind Scale. By 18:00 UTC, they dropped to 167 km/h (103 mph), which made it a Category 2 hurricane equivalent, still extremely dangerous.

Category 4 hurricane can have the following effects: Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

"Northern Madagascar will experience damaging winds and heavy rainfall into Wednesday," AccuWeather Senior Meteorologist Jason Nichol said. Even though significant weakening is expected as the cyclone moves farther inland, the provinces of Antsiranana and Toamasina will remain at risk for life-threatening flooding rain and destructive wind gusts in excess of 160 km/h (100 mph) into Wednesday.

The damage caused by floods could potentially affect 8 regions: Analanjirofo, Atsinanana, Sofia, Alaotra Mangoro, Analamanga, Menabe, Vatovavy Fitovinany, and Atsimo Andrefana.

Drought-stricken Madagascar will likely receive between 700 and 900 mm (27 and 36 inches) of rain this week.

nawo is being compared to the last hurricane-strength tropical cyclone Giovanna that made landfall on Madagascar's east coast on February 13, 2012. Giovanna is blamed for 33 deaths along the Madagascar coast, and was the first intense tropical cyclone to impact Madagascar, since Bingiza in February 2011.

Since 1983, Madagascar has been struck by 12 major tropical cyclones. The deadliest was Tropical Cyclone "Gafilo" on March 7, 2004. Gafilo was also a Category 4 storm with 241 km/h (150 mph) winds and was responsible for deaths of 363 people.

According to Weather Underground meteorologist Jeff Masters, Enawo is the strongest tropical cyclone in the Southern Hemisphere so far in the 2016 - 2017 season, and the first one to exceed Category 1 strength. "It has been an unusually quiet tropical cyclone season in the Southern Hemisphere this year, as we discussed in detail in a February 28 post," he noted and added:

"Of most concern are the rains from Enawo, as it is an unusually large and wet storm. The amount of water vapor detected by satellite is near the very high end of what is observed in tropical cyclones—precipitable water values up to 3.0 inches. Recent runs of the HWRF model predict extreme rainfall amounts falling on heavily populated regions of Madagascar, and Enawo has the potential to be a top-three most damaging storm in the island’s history.

Enawo will decay rapidly as it takes a track directly down the length of Madagascar, exposing the entire island to flooding rains. However, the disaster could have been worse—more than half of the rivers in Madagascar have dried up or are flowing at less than 5 percent of their average streamflow, thanks to a two-year El Nińo-linked drought. Enawo’s rains will help break the drought, which has caused large-scale crop failures and put over half a million people into acute food insecurity."

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Strongest cyclone in 13 years hits Madagascar
The strongest cyclone to hit Madagascar in 13 years has made landfall on the northeastern coast of the island nation on Tuesday.

Cyclone Enawo was packing winds of 230 kilometres per hour when it made landfall, with stronger gusts of up to 270 kph and a central pressure of 925 millibars, making it equivalent to a power category 4 hurricane.

The last time Madagascar experienced a storm of this magnitude was in March of 2004 when Cyclone Gafilo made landfall in approximately the same location, claiming 236 lives and destroying over 20,000 homes.

Even though it has been over 24 hours since the storm made landfall between the coastal communities of Farahalana and Antalaha, the amount of rain from the remnants of Enawo is still expected to cause dangerous flash flooding and mudslides through late week.

With 89 percent of Madagascar's roads being dirt, getting into the hardest hit areas of the north and east will be difficult. Very little information has yet to come out of those regions, but it is expected that there will be widespread power outages from down trees and extensive flood damage.

Reports of casualties and injured were expected to rise in the coming days.

Through Thursday the storm will continue to move south across the island, continue to bring with it heavy rainfall and gusty winds. By Friday, what is left of Enawo will have exited the southern tip of the country and back into the Indian Ocean.

Normally the Indian Ocean sees 4-5 "hurricane strength" cyclones each year. Cyclone Hellen was the last cyclone to make landfall in Madagascar in March, 2014

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Six people killed by Enawo

At least six people have been killed, 7 injured and more than 760 000 affected in nine regions as Enawo, the third strongest cyclone to hit Madagascar, hit the island on March 7, 2017. Towns and cities were flooded, houses, schools, hospitals and critical infrastructure destroyed and thousands of people displaced. Water and power outages are widespread in affected areas. The full extent of the damage is as yet unknown due to poor communication and difficulty reaching affected areas. The death toll is expected to rise.

Slow-moving Enawo hit the country as Category 4 hurricane equivalent at 08:00 UTC (11:00 local time) on Tuesday, March 7, about half way between Sambava and Antalaha. As it hit, Enawo became quasi-stationary and pounded Antalaha with strong winds and heavy rain for several hours.

At 09:00 UTC (4 a.m. EST) its maximum sustained winds were 231 km/h (144 mph). By 18:00 UTC, they dropped to 167 km/h (103 mph), which made it a Category 2 hurricane equivalent, still extremely dangerous. By March 8, Enawo weakened from an “intense” to a “moderate” tropical storm, with an average speed of 80 km/h (50 mph) with peaks of 112 km/h (70 mph).

The tropical cyclone dropped the highest rainfall totals of over 500 mm (almost 20 inches) in the open waters of the Indian Ocean northeast of Madagascar.

Madagascar was expected to receive between 700 and 900 mm (27 and 36 inches) of rain this week, which will come as a blessing to some as the country suffers from severe and chronic drought, particularly in the south of the country. More than 850 000 people are severely food insecure.

UNOCHA and the Government of Madagascar reported March 9 that the northeastern Sava region has sustained significant damage to housing and agriculture.

Antalaha port is inaccessible and more than half of the city’s homes have been destroyed, with northern areas particularly affected. Farahalana commune is flooded by Lohoko River, with half of all housing under water. Farms along the famous Vanilla Coast have been hard hit, while rice fields in Antalaha and Sambava are submerged.

Carcasses of migratory birds have washed up on the shores of Fenerive Est in the Analanjirofo region, where more than 10 000 people are displaced. Two school buildings have collapsed, an airport road blocked, and more than 500 houses flooded in the districts of Mananara Nord, Maroantsetra, Vavatenina and Soanierana Ivongo. Flood waters in Maroantsetra have attained a height of four meters (13 feet).

The Malagasy Red Cross reports that evacuations are underway in the flood-affected cities of Brickaville and Toamasina I & II in Antsinanana region.

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Cycloon kost leven aan 38 mensen op Madagaskar

De tropische cycloon Enawo, die dinsdag op Madagaskar aan land kwam, heeft het leven gekost aan 38 mensen, 180 mensen verwond en 53.000 anderen dakloos gemaakt.
Het nationale rampenbureau van Madagascar maakte het slachtoffertal zaterdag bekend, meldt AP. Het is aanzienlijk hoger dan eerdere schattingen, waarin werd gerept over vier doden en tienduizend ontheemden.

Enawo bereikte windsnelheden van meer dan 230 kilometer per uur

Vooral de hoofdstad Antananarivo is zwaar getroffen, zei het rampenbureau. Daar zijn meer dan 32.000 mensen dakloos geraakt.

Volgens het Rode Kruis kunnen tot zevenhonderdduizend mensen negatieve gevolgen ondervinden van de cycloon. Het was de krachtigste storm die landval maakte in Madagaskar sinds 2012, toen meer dan honderd mensen omkwamen door cycloon Giovanna.

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Evacuaties in Nieuw-Zeeland vanwege komst orkaan Cook


Grote delen van de noordoostkust van Nieuw-Zeeland wordt geėvacueerd vanwege de komst van orkaan Cook.

De autoriteiten waarschuwen voor hoge golven, gevaarlijke stormvloed en aardverschuivingen door het slechte weer. De storm kan windsnelheden bereiken tot 150 kilometer per uur. Eén persoon is reeds om het leven gekomen.

In noordelijke gedeeltes van Nieuw-Zeeland is de noodtoestand uitgeroepen. Inwoners in lage gebieden worden opgeroepen om onmiddelijk hun huis te verlaten. Meer dan honderd scholen zijn gesloten. Ook universiteiten hebben uit voorzorg hun lessen geschrapt. Media in het land melden dat sommige regio's last ondervinden van grote stroomstoringen.

Luchtvaartmaatschappij Air New Zealand waarschuwt voor "significante verstoringen" vanwege het weer. Veel vluchten zullen vertraagd worden of geheel worden geannuleerd. Mogelijk wordt ook de Auckland Harbour Bridge gesloten voor het verkeer, een zeer belangrijke verkeersader in het land.

Cook volgt op slechts enkele weken na de schade aangericht door orkaan Debbie.

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Cyclone Cook: New Zealand braces for 'worst storm in decades'

Auckland residents told to cancel Easter plans as the cyclone heads directly for the flood-stricken Bay of Plenty region.

Cyclone Cook is bearing down on New Zealand and is expected to make landfall on Thursday evening, heading directly for the flood-stricken Bay of Plenty region devastated by last week’s Cyclone Debbie.

Two states of emergency have been declared in the North Island east coast districts of Bay of Plenty and Thames-Coromandel, with more districts expected to make that call mid-afternoon when the ferocity of the storm becomes clear.

MetService – whose website crashed on Thursday because of heavy traffic – has warned the approaching storm system is expected to be the worst New Zealand has seen in decades, with forecasters comparing it to 1968’s Cyclone Giselle, which sunk the Wahine ferry, killing 52 people.

MetService meteorologist Lisa Murray said she was concerned New Zealanders weren’t taking the storm threat seriously enough and the approaching cyclone was the worst weather event she had seen in her 12 years as a forecaster.

“This is not an event to be taken lightly. Prepare for loss of power and isolation due to road closures,” she said in a video shared by thousands on social media.

Heavy downpours, gale force winds of 150 kph and storm surges up to five metres are predicted to batter the east coast, where the town of Edgecumbe remains under-water, its 2,000 residents staying with extended family and in maraes and evacuation centres, unable to return to their flooded homes.

Evacuations of low-lying areas on the east coast of the North Island are under way, with power outages, fallen trees and roofs lifting off homes possible, according to the MetService, as well as widespread and “significant” flooding across the entire North Island.

Civil Defence has pleaded with New Zealanders to take the storm “seriously”, prepare emergency supplies for three days and “not take any chances”.

Aucklanders are being advised to cancel their Easter holiday plans and hunker down at home until the storm passes, with Auckland Transport asking people who work in the central city to stay home today, and Auckland University closing at 11am.

The Auckland Harbour Bridge may close if wind gusts increase, and ferries across the harbour are expected to be cancelled.

Volunteers and emergency responders have been working all week to prepare relief supplies for people in the eye of the approaching storm, with significant donations of meat, dry goods and animal feed flowing to the Bay of Plenty from around the North Island, as it braces for its second major weather event in a week.

A month’s worth of rain is expected to fall in the space of a day on the east coast, with the ground already sodden and covered in up to a metre of mud and debris.

Landslides have closed access to the Far North district, with many more slips reported and uncleared around the North Island. The New Zealand Transport Authority has asked Kiwis to cancel all non-essential travel and avoid driving if at all possible.

Air New Zealand has said major disruptions and delays are expected to all its services country-wide.

Landslides, flooding and possible evacuations are also expected in some parts of the east coast of the south island, although they will be less severe than in the North Island.

Dunedin city council has asked anyone living in low-lying areas to door-knock on their neighbours to check if they are OK, and to sandbag or self-evacuate if they are concerned about flooding risks.

twitter:

NiwaWeather twitterde op woensdag 12-04-2017 om 06:39:10 Our super high-resolution 1.5 km model shows #CycloneCook making landfall just south of Whangamata on Thursday even... https://t.co/fltUSfNiLj reageer retweet

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Op woensdag 19 april 2017 16:31 schreef heywoodu het volgende:

[..]

Die vraag wil ik bij dezen graag herhalen, want ik heb werkelijk geen flauw benul waar ik naar kijk behalve dat ik wel zie welk gebied op aarde het is

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Difference Between Tropical And Subtropical Storms

When an area of low pressure forms over waters with sea-surface temperatures of at least 70 degrees, a subtropical low can form. This is due to the core of the storm becoming warm, deriving some of its energy from latent heat, or energy released when water vapor that evaporated from the warm water is condensed into liquid.

A subtropical depression or storm exhibits features of both tropical and non-tropical systems. This includes no cold or warm fronts, a broad wind field and thunderstorms removed some distance from the center.

Subtropical storms also tend to have a large, cloud-free center and a less symmetric wind field. Maximum sustained winds are also much farther from the center, while the strongest winds in a tropical storm are close to the center.

Subtropical cyclones typically are associated with upper-level lows and have colder temperatures aloft, whereas tropical cyclones are completely warm-core and upper-level high-pressure systems overhead help facilitate their intensification.

The NHC still issues advisories and forecasts for subtropical depressions and storms. They are assigned a number or name, just like a tropical depression or storm.

If the subtropical storm remains over warm water, thunderstorms can build close enough to the center of circulation, and latent heat given off aloft from the thunderstorms can warm the air enough to make the storm a fully tropical storm.

As a result, the strongest winds and rain become closer to the center and, with time, further intensification becomes possible.

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Tropical Storm Arlene forms, poses no threat to land

Tropical Storm Arlene is the first named storm of 2017.

Arlene formed Thursday afternoon in the Atlantic Ocean about 800 miles west of the Azores Islands, the National Hurricane Center said in a 5 p.m. Thursday advisory.

The storm was no threat to land.

She is a rarity, though.

“Tropical storms in April are rare and Arlene is only the second one observed in this month during the satellite era,” wrote senior hurricane specialist Lixion Avila in a forecast discussion posted on the National Hurricane Center’s website.

“It should be noted, however, that this type of storm was practically impossible to detect prior to the weather satellite era.”

Arlene’s maximum sustained winds were at 45 mph. The storm was traveling toward the west-northwest at about 25 mph. Tropical storm-force winds were extending out about 105 miles from the storm’s center, the hurricane center said.

Arlene’s lifespan was expected to be short, with the storm expected to dissipate on Friday.

On Monday, the hurricane center said it was monitoring a patch of rough weather in the Central Atlantic that was expected to have a low chance of becoming a subtropical cyclone.

On Wednesday it became a subtropical depression. By Thursday morning it was a tropical depression. Then, on Thursday afternoon, it strengthened into Tropical Storm Arlene.

Rare subtropical depression forms in the Atlantic
Rare subtropical depression forms in the Atlantic
Avila was candid, and said the development was surprising.

“I have to add one more surprise to my long hurricane forecasting career,” Avila wrote in the discussion. “Unexpectedly, the subtropical cyclone became a tropical depression this morning, and then it intensified to a tropical storm.”

Although it’s not the Atlantic hurricane season yet, forecasters always warn that tropical depressions, storms, and hurricanes don’t pay attention to calendars. Such storms can happen anytime, they warn.

The Atlantic hurricane season officially begins June 1 and runs through Nov. 30.