US-based storm-chaser Josh Morgerman has warned that Cyclone Debbie is shaping up to look like a "worst case scenario" for Queensland as it approaches land.
The self-described "hardcore hurricane chaser" flew to Brisbane from California on Monday and headed to Emerald and Proserpine before bunkering down in Bowen, where he is hoping to feel the eye wall of the storm.
He told news.com.au the cyclone looked like "garbage all day" but became extremely symmetrical and circular on Monday afternoon, a sign it was growing in intensity.
"The more symmetrical and perfectly rounded, the more intense it is," he said.
"That's a worst-case scenario, storms that are rapidly strengthening as they approach the coast. That's a real concern and I am worried about the impact.
"A steady-state storm or a weakening one is better than one that's intensifying as they approach the coast."
has chased hurricanes across the US, Mexico and Asia, capturing raw data from inside the eye wall in a series of hair-raising videos online.
However Debbie was the drawcard for his first trip Downunder, where he's been battling driving on the opposite side of the road and winds in the opposite direction to what he's used to.
"I want to get right in that eye," he said. "The air pressure in the eye is one of the most telltale signs of a cyclone's true intensity."
Morgenman spent the afternoon stocking up on supplies and researching the best place to bed down for the storm, which is due to make landfall late this morning.
He stayed last night in a "creaky old roadside motel" and thanked Queenslanders for their hospitality in posts online.
Emergency services have warned those in low-lying areas near Mackay to leave and stay with friends before the Category 4 storm makes landfall.
Mackay police issued an evacuation order to residents and said only those with no other option should arrive at the cyclone shelter.
Queensland fire and emergency services have warned people to turn off electricity and gas and unplug appliances. They're also warning people to shelter in the strongest room of their homes, keep an emergency kit close by and listen to the radio or watch the Bureau of Meteorology website for updates.
Despite the potential hazards, Morgerman said the "number one golden rule" of storm-chasing was not to be a distraction or get in the way of emergency services.
"I've been in situations where I've rescued people, so my role is just to help and not to hinder and not to ask for help," he said.
"This is a potentially very dangerous cyclone. People in the warning area need to take this seriously. If you've been in them before, don't be fooled.
"Be in a space place, have a safe space and don't travel around in it."