The storm's approach has prompted Woodside Petroleum to temporarily shut its Cossack-Pioneer and Legendre oil fields, a spokesperson told Reuters today.

But production at Woodside's 40,000 barrel per day Enfield oil field, which is not in the cyclone's path, has not been affected.

Cossack-Pioneer has a production capacity of 100,000 bopd, while Legendre produces 7000 bopd.

In addition, Santos closed its 50,000-barrel Mutineer-Exeter oil field on Monday, according to a Bloomberg report. Production is expected to restart on the weekend.

The Bureau of Meteorology told ABC News that the cyclone may become a category 4 storm before it crosses the coast tonight.

"The industry and offshore installations may be particularly affected by this cyclone," a spokesperson told the ABC.

"It's already causing fairly strong winds offshore."

Cyclone George was 350km north of Port Hedland this morning and moving south at 20km/hr.

Port Hedland, Wickham, Karratha, Dampier and Onslow have been put on blue alert.

The Apache-led Harriet Joint Venture has also halted drilling at its latest Carnarvon Basin exploration well. This follows earlier disruptions at Nexus Energy’s Crux project in the Browse Basin and AED Oil’s Puffin project in the Timor Sea.

In a statement, JV partner Tap Oil said personnel were yesterday morning evacuated from the Wonnich Deep-1 well in production licence TL/8, which had reached a depth of 4100m.

Nexus and AED Oil yesterday started re-manning the rigs at their respective offshore projects, after drilling was halted due to the cyclone’s approach.