Update, 11.15am: A Severe Thunderstorm Watch remains in force for Bay of Plenty, Rotorua and Gisborne, following the Severe Thunderstorm Warning being lifted earlier.

This warning affects people in the Opotiki, Whakatane, Kawerau and Rotorua areas, and remains valid until 12noon.

"At 11am, MetService weather radar detected severe thunderstorms near Kawerau, Edgecumbe, Matahina, Te Teko, Rotoehu, Otakiri and Waiohau," says a MetServices spokesperson.

"These severe thunderstorms are moving towards the southeast, and are expected to lie near Ruatoki North, Waiohau and Matahina at 11.30am and near Matahi at midday."

These thunderstorms are expected to be accompanied by very heavy rain and possible tornadoes.

Very heavy rain can cause surface and/or flash flooding about streams, gullies and urban areas, and make driving conditions extremely hazardous.

Tornadoes can blow out windows, lift roofs, break large branches off trees, generate dangerous flying debris and blow vehicles off the road.

A Severe Thunderstorm Watch remains in force for Bay of Plenty, Rotorua and Gisborne.

The National Emergency Management Agency advises that as storms approach you should:
- Take shelter, preferably indoors away from windows;
- Avoid sheltering under trees, if outside;
- Get back to land, if outdoors on the water;
- Move cars under cover or away from trees;
- Secure any loose objects around your property;
- Check that drains and gutters are clear;
- Be ready to slow down or stop, if driving.

During and after the storm, you should also:
- Beware of fallen trees and power lines;
- Avoid streams and drains as you may be swept away in flash flooding.

Update, 10.52:  A MetService spokesperson says the Severe Thunderstorm Warning for Bay of Plenty has been lifted.

"However isolated thunderstorms with possible strong wind gusts and/or small tornadoes continue to affect eastern Bay of Plenty," says a MetService spokesperson.

"A Severe Thunderstorm Watch remains in force until 2pm today."

Initial report 10.10, MetService has issued a severe thunderstorm warning that may affect people living in Western Bay of Plenty, Tauranga and Rotorua.

At 9.52am, MetService weather radar detected severe thunderstorms near Tauranga, Te Puke, Mount Maunganui, offshore Mount Maunganui, and Papamoa.

"These severe thunderstorms are moving towards the southeast, and are expected to lie near Te Puke, Papamoa and Paengaroa at 10.22am, and near Te Puke, Pukehina, Pongakawa Valley and Paengaroa at 10.52am," says a MetService spokesperson.

"These thunderstorms are expected to be accompanied by torrential rain and damaging wind gusts."

Torrential rain can cause surface and flash flooding about streams, gullies and urban areas, and make driving conditions extremely hazardous.

Very strong wind gusts can break branches from trees, damage roofing, and make driving hazardous especially for high-sided vehicles and motorcycles.

A Severe Thunderstorm Watch remains in force for Bay of Plenty, Rotorua and Gisborne on Wednesday mroning. 

The National Emergency Management Agency advises that as storms approach you should:
- Take shelter, preferably indoors away from windows
- Avoid sheltering under trees, if outside
- Get back to land, if outdoors on the water
- Move cars under cover or away from trees
- Secure any loose objects around your property
- Check that drains and gutters are clear
- Be ready to slow down or stop, if driving.

During and after the storm, you should also:
- Beware of fallen trees and power lines;
- Avoid streams and drains as you may be swept away in flash flooding.