Image source, DAU TIEN DAT/EPA/Shutterstock

Vietnam has been hit by Asia's most powerful tropical storm so far this year, Typhoon Kalmaegi, which made landfall on Thursday with winds of 92 mph (148km/h).

The government says the storm hit the provinces of Dak Lak and Gia Lai, where thousands of people have been evacuated from their homes, and several airports are closed.

The storm has torn the roofs off houses, uprooted trees and shattered glass panels on buildings.

In Dak Lak, some people have reported their homes have collapsed and flooded, as strong winds and rain batter the area.

Vietnam's weather service has warned of the risk of flooding and landslides.

Before the storm began, Vietnam was already battling serious floods after heavy rains in recent weeks.

Some 260,000 soldiers are on standby to help with storm relief.

Typhoon Kalmaegi has already caused widespread destruction in the central Philippines, killing at least 114 people.

We are now pausing our live coverage, but you can stay up to date with the latest on Typhoon Kalmaegi here.

Matt Taylor
BBC Weather

While the recovery and clean up following Typhoon Kalmaegi is underway, authorities are also watching for the possibility of another typhoon hitting the country this weekend.

Tropical Storm Fung-Wong, known locally as Uwan, has now formed in the west Pacific.

This is forecast to strengthen over the coming days and become a “very strong typhoon” before making landfall in the Philippines sometime either later Sunday or Monday.

Forecasts issued by the Japan Meteorological Agency show the track of the storm is likely to be much further north than that of Kalmaegi, with the landfall possible on the island Luzon.

However, we are still likely to see moisture-laden winds drawn in across Cebu and further intense rainstorms on the island.

Matt Taylor
BBC Weather

Kalmaegi, locally known as Tino, brought more than a month’s worth of rain to parts of Cebu in less than a day, including to the provincial capital Cebu City where over 180mm (7 inches) fell.

Such highly urbanised locations especially struggle to cope with this intensity and volume of rain, resulting in flash flooding.

A wet monsoon season in the run up to Kalmaegi has also meant a highly saturated ground and high rivers have struggles to hold the water.

Then there is the storm itself.

Seas around the Philippines, and Vietnam are currently 1-3C warmer than normal. The warmth not only fuels the storm, but it feeds it with extra moisture that ultimately falls out as rain.

As the world warms, the ability of the atmosphere to hold moisture increases – with every 1 degree of warming the atmosphere can hold an extra 7% moisture, meaning rainfall amounts in such storm can be greater and more intense.

Sen Nguyen
Reporting from Bangkok

About 30 minutes after the typhoon made landfall, hundreds of residents in two communes of Dak Lak province called for help, local media reported.

Many people reported that their homes had collapsed or been flooded, while strong winds and heavy rain continued to batter the area.

Dak Lak province is approximately 350km (215 miles) north east of Ho Chi Minh City.

Hurricanes are tropical storms that form over the North Atlantic Ocean and Northeast Pacific.

Cyclones are formed over the South Pacific and Indian Ocean.

Typhoons are formed over the Northwest Pacific Ocean.

Collectively, these storms are referred to as tropical cyclones.

Tropical cyclones are characterised by very high wind speeds, heavy rainfall, and storm surges - short-term rises to sea-levels. This often causes widespread damage and flooding.

They begin as atmospheric disturbances, external - such as, for example, a tropical wave, an area of low pressure where thunderstorms and clouds develop.

As warm, moist air rises from the ocean surface, winds begin to spin. The process is linked to how the Earth's rotation affects winds in tropical regions just away from the equator.

Sen Nguyen
Reporting from Bangkok

Vietnam's military has deployed more than 260,000 soldiers and personnel, along with over 6,700 vehicles and pieces of equipment, including six aircraft, to help with storm relief efforts.

All units are on standby for search and rescue operations in response to the typhoon.

Viettel, a military-owned conglomerate, has also announced that it will support the rescue efforts using fly-cams - technology that remains uncommon in Vietnam's disaster relief operations.

The Vietnamese government's online portal is sharing figures about the typhoon's windspeeds when it made landfall a little earlier.

It says there were maximum sustained winds of up to 92 mph (149 km/h).

Sen Nguyen
Reporting from Bangkok

Image source, DAU TIEN DAT/EPA/Shutterstock

The Vietnamese national weather forecaster says hundreds of localities in seven cities and provinces are at risk of flooding and landslides in the next six hours, according to a notice issued earlier today.

There have already been reports of damage from several provinces, including roofs torn off homes, shattered glass panels at hotels, and trees uprooted or snapped along city streets and rural roads by powerful gusts.

Typhoon Kalmaegi has just hit Vietnam's coastline, bringing winds of up to 149 kilometres (92 miles) per hour, according to reports in online Vietnamese newspaper VnExpress.

Trees have fallen on main roads, blocking access, while windows in hotels in the Quy Non area have smashed.

"The storm is on land, in the provinces of Dak Lak and Gia Lai," the environment ministry has said in a statement being quoted by various outlets, including the AFP news agency.

Typhoon Kalmaegi has made landfall in central Vietnam.

Stick with us, we'll bring you the latest in our next few posts.

Here are some more pictures of what's happening in Cebu City, in The Philippines, which was hit by Typhoon Kalmaegi after it swept the Central Visayas region.

Emergency responders are continuing to work to find survivors at the site of a landslide, caused by the heavy rains.

Mud has swept through buildings including branches of McDonalds, where workers are trying to shift the deluge.

Image source, EPA

Image source, Reuters

Matt Taylor
BBC Weather

Typhoon Kalmaegi may be hitting an area much further south than those affected by Typhoon Ragasa in September, but heavy rains in central Vietnam have not only caused extensive flooding in recent weeks - it's left the ground saturated and rivers high.

Further rainfall will likely lead to more flood impacts quite rapidly.

Forecasts predict between 200-400mm of rain to fall, with high resolution weather computer models hinting at the possibility of up to 600mm in a few spots.

The remnants of the storm could also impact parts of Cambodia and eastern Thailand as it moves inland over the coming days.

Forecasts of up to 150mm or rain are possible in parts of northern Cambodia and parts of Surin, Si Sa Ket and Ubon Ratchatani in Thailand.

Image source, Reuters

Ahead of Typhoon Kalmaegi's arrival, it's worth noting that Vietnam has already been battling with floods and record rains this week.

Burst riverbanks have flooded some of the country's most popular tourist spots, including the Unesco-listed city of Hue and historic hotspot Hoi An - where residents have been pictured navigating the city via wooden boats after the Hoai river overflowed.

At least 35 people have been killed in the deluge, according to a recent statement from the national disaster agency. Vietnam's environment ministry also says more than 100,000 homes have been flooded and more than 150 landslides reported.

According to local media reports, PM Pham Minh Chinh held an online meeting to direct the emergency response.

"We must reach isolated areas and ensure people have food, drinking water, and essential supplies. No one should be left hungry or cold," he's cited as saying.

Sen Nguyen
Reporting from Bangkok

Seaside communities in Vietnam are expected to be hit hard.

A sea-level rise of 4 to 6m (13 to 20ft) in at least two provinces could capsize boats and devastate fishing farms, according to a forecast issued at 16:00 local time (9:00 GMT) by a senior official at Vietnam’s National Center for Hydro-Meteorological Forecasting.

Meanwhile, deputy director Nguyen Xuan Hien says Typhoon Damrey - which struck Vietnam in 2017 with less intensity than Kalmaegi, but still caused severe damage to coastal communities - should serve as a warning, urging people to remain highly alert.

Thailand is also bracing for the storm's impact. Local officials have warned of flash floods, landslides and river overflows.

Typhoon Kalmaegi is the 20th tropical cyclone to hit the Philippines this year.

As those in Vietnam now brace for its impact, let's take a look at its trajectory.

• On Tuesday, the storm made landfall in the Philippines - it went on to flood whole towns and kill at least 114 people
• Tens of thousands of people were evacuated, particularly from central areas including the island and tourist hotspot of Cebu - early on Thursday, Philippines President Ferdinand Marcos Jr declared a state of emergency
• The typhoon has gathered in strength and is expected to hit Vietnam later on Thursday. It could generate waves of up to 8m (26 ft) on the South China Sea, according to Vietnam's weather bureau
• Thousands of people who live in coastal communities have been asked to evacuate ahead of its arrival, with Vietnam's Deputy Prime Minister Tran Hong Ha calling Kalmaegi a "very abnormal" storm that should be treated with urgency

We've an update on flights in Vietnam - something we reported on a little earlier.

The country's government now says six airports in total have been told to close, ahead of the storm making landfall.

In the statement, officials say the closure of five in particular will affect hundreds of flights in Vietnam. They are:

• Buon Ma Thuot
• Pleiku
• Tuy Hoa
• Chi Lai Phu Cat
• Lien Khuong

The typhoon is expected to land just north of the coastal city of Quy Nhon, where thousands of people have been ordered to evacuate.

Earlier today, a reporter from AFP news agency saw officials knocking on doors and warning people to flee.

Some 100,000 households have been evacuated from the neighbouring province of Gia Lai, as of noon local time (05:00 GMT).

As of a couple of hours ago, local authorities urged those who haven't evacuated to stay indoors.