Topic: Tasman Low causes severe weather on Lord Howe Island: 18 - 22 April 2009

[Michael Bath]

A low has been active in the Tasman Sea for a number of days, whipping up big seas along the NSW coast and some heavy rainfalls particularly in the Port Macquarie area overnight.

However, the stand-out effect so far is the impact on Lord Howe Island on Sunday afternoon and evening (19th April). Convective activity resulted in over 240mm of rain - 140mm of which fell in two hours. Winds gusts peaked at 146km/h. It was reported on the tropical cyclone list that the low exhibited tropical cyclone characteristics during this severe weather.

Heaviest April rain in 20 years for Lord Howe Island

Lord Howe Island has been drenched with the heaviest April rainfall in at least 20 years, according to weatherzone.com.au.

The island received a whopping 241mm in the 24 hours to 9am today, its highest April daily rainfall in 20 years of records. This was also its third highest daily rainfall total on record for any month.

The bulk of the rain fell between 8pm and midnight, when a stationary area of heavy rain and thunderstorms sat over the island.

"An intense low pressure system is situated approximately 250 km north of Lord Howe Island. Heavy bands of rain and thunderstorms have been circulating around this low," weatherzone.com.au meteorologist Matt Pearce said.

"The low is now slowly moving away to the northeast so the rain has eased considerably across the island today."

In addition to the heavy rain, severe winds were reported yesterday evening. A gust of 150km/hr was recorded at 8:25pm.

"These severe winds were associated with heavy showers and thunderstorms that were crossing the island yesterday evening," Pearce said.

A Severe Weather Warning remains in force for Lord Howe Island warning of the potential for gusts in excess of 90 km/h.

"Although the immediate threat of severe winds and rain has eased, the low pressure system is likely to continue wandering around the Tasman Sea through the rest of the week, so gusty winds and showers will persist," Pearce said.

SES to assist battered Lord Howe

Tuesday April 21, 2009 - 08:50 EST

The NSW State Emergency Service will send 20 volunteers to Lord Howe Island, after violent storms caused extensive damage to homes, businesses and the airport.

On Sunday night, winds gusting up to 150 kilometres an hour ripped through the Island, which was also inundated with 230 millimetres of rain in just three hours.

The wild weather caused flash flooding, roof damage and left the airport unserviceable to all but light aircraft.

Steve Delaney from the SES says workers have a big job ahead of them.

"There's a lot of debris all over the Island with a couple of the homes actually suffering some structural damage and also the northern end of the Island has actually lost power due to damage to the generation plant," he said.

Mr Delaney also says a lot of repair work will be needed to reopen the Island's airport.

"The actual pavement on the runway has been damaged by water," he said.

"There is access at this stage to light aircraft. Whether or not it can be repaired will be open to judgement and investigation and analysis by the engineers who will be going over with our crew."

The New South Wales Emergency Services Minister, Steve Whan, says the focus for emergency workers on Lord Howe Island is to restore its airport as quickly as possible.

"As a result of the storm damage, the airport is closed to larger planes at the moment. Now that's obviously pretty critical for Lord Howe as an economy reliant on tourism," he said.

"So the SES workers plus a couple of engineers from the Department of Commerce are going out to help with the clean-up and just making sure that the airport is able to be reopened for tomorrow or the day after."

- ABC

[Michael Bath]

A track map of the low can be found here:

http://australiasevereweather.com/cyclones/2009/200904_tasman_low.htm

MB

[Peter J]

I have been tracking the ECL, and if it were more tropical, i think it could have reached Cat2-3 TC level. It certainly was close to a strong cyclonic storm, and to get 200+mm in 3 hrs is very much a possibility from cyclonic storms. It's a lot of rain in such a short time.

Big Pete

[nzstorm]

Lord Howe Island for its oceanic locale has quite a thundery climate, averaging about 40 thunder days a year from memory. That beats a lot of mainland Australia!   Interesting report on the rainfall.

[Michael Bath]

Attached are the Lord Howe Island observations for the month of April - quite a wet and windy period for them.

544mm smashes the previous April report of 257mm (avg 113mm). The 146km/h wind gust is also the record for April, though just under the all time record of 148km/h on 22 May 1992.

Attached image sourced from here

[Michael Bath]

The complete track map is now available. It shows the low did one and a half clockwise loops of the Tasman Sea :

http://australiasevereweather.com/tropical_cyclones/2008_2009/oper/tropical_cyclone_subtrop-low-01.htm