Cyclone Nathan targets Queensland, Australia with Cat 4 landfall

Tropical cyclone Nathan is heading for a landfall on the northern Queensland coast as a strong category 4 storm, with damaging and potentially dangerous winds and storm surge expected on Friday in the early hours.

Tropical cyclone Nathan has been a very difficult storm for forecasters to predict, as it made an approach towards northern Queensland days ago but recurved back out to sea. Nathan then recurved again and headed straight back towards the coast, intensifying all the time.

Now, the latest forecast suggests a strong category 4 landfall for cyclone Nathan, somewhere between Cairns and Cape Melville. At the moment Cape Flattery and Cooktown seem closest to the storms eventual landfall and are likely to experience the worst weather conditions as Nathan approaches and a potentially severe landfall blow.

Tropical cyclone Nathan forecast path and intensity

Cyclone Nathan continues to intensify and conditions remain conducive for the moment. So a strong Category 4 landfall, as is currently forecast, could perhaps go higher. As a Cat 4 storm Nathan could bring sustained winds of well over 150kph. At landfall the Australian Bureau of Meteorology says that wind gusts of as much as 290kph could be felt in the coastal regions most affected by cyclone Nathan.

Landfall is expected to occur in the early hours of Friday morning local time. Towns and communities in the storm’s path are recommended to make preparations early.

Insurance exposures in the area are not as high as further south. If Nathan deviated further towards Cairns the impact to the insurance industry could be much higher.

There is also the potential for some disruption and damage as a second landfall is forecast once the storm crosses the Cape York Peninsula and emerges back over warm seas where re-intensification is a real possibility. A second landfall is forecast by the JTWC, as you can see from its tracking map below.

JTWC tracking map for tropical cyclone Nathan

As ever there is the potential for losses for insurers and reinsurers and as we always point out an increasing exposure to these events in the ILS market. Some catastrophe bonds have direct exposure to Australian cyclone risks and collateralized reinsurance markets increasingly look for access to Australian perils.

We’ll update should the outlook worsen in the coming day.

The latest forecast from the Bureau of Meteorology can be found below:

Details of Severe Tropical Cyclone Nathan at 7:00 am EST:

Intensity: Category 3, sustained winds near the centre of 140 kilometres per hour with wind gusts to 195 kilometres per hour.

Location: within 30 kilometres of 14.7 degrees South 147.9 degrees East, estimated to be 305 kilometres east northeast of Cooktown and 335 kilometres northeast of Cairns.

Movement: west at 10 kilometres per hour.

Severe tropical cyclone Nathan is continuing its westward movement towards the north Queensland coast. Further intensification is expected before the system makes landfall as a category 4 cyclone, most likely between Cape Melville and Cape Tribulation early on Friday morning.
Hazards:

The VERY DESTRUCTIVE CORE of severe tropical cyclone Nathan, with maximum wind gusts forecast to reach 260 km/h, is expected to make landfall between Cape Melville and Cape Tribulation early on Friday morning.

GALES with gusts to 120 km/h currently extend out to approximately 130 kilometres from the centre of the cyclone. GALES may develop about coastal and island communities between Lockhart River and Cairns late this afternoon or tonight, before extending inland to areas including Palmerville and Laura on Friday morning.

DESTRUCTIVE WINDS extend out to about 70 kilometres from the centre of the cyclone and may begin to affect coastal and island communities between Cape Melville and Port Douglas overnight Thursday into early Friday morning.

Coastal residents between Cape Melville and Cairns are specifically warned of the dangerous storm tide that could occur as the cyclone crosses the coast. The sea is likely to rise steadily up to a level well above the normal tide, with damaging waves and flooding of some low-lying areas, which could also extend some way inland. People living in areas likely to be affected by this flooding should take measures to protect their property as much as possible and be prepared to follow instructions regarding evacuation of the area if advised to do so by the authorities.

Heavy rainfall, which may lead to flash flooding, may develop late Thursday but will most likely occur during Friday as the cyclone crosses the coast.

The latest update from Aon Benfield’s Impact Forecasting unit:

LATEST DETAILS ON NATHAN
COORDINATES: 14.7° south, 147.9° east (previous location: 14.9° south, 149.4° east)
LOCATION: 355 kilometers (220 miles) northeast of Cairns, Australia
MOVEMENT: west at 11 kph (7 mph) (previous: southwest at 2 kph (1 mph))
WINDS: 150 kph (90 mph) with gusts to 185 kph (115 mph) (previous: 75 kph (45 mph))
RADIUS OF TROPICAL STORM-FORCE WINDS: 205 kilometers (125 miles)
RADIUS OF HURRICANE-FORCE WINDS: 55 kilometers (35 miles)
MINIMUM CENTRAL PRESSURE: 963 millibars (previous: 989 millibars)
SAFFIR-SIMPSON SCALE RANKING*: Category 1

LANDFALL AND LOSS PROBABILITIES

FORECAST LANDFALL LOCATION: just north of Cooktown, Australia
FORECAST LANDFALL TIMEFRAME: early Friday morning local time (AEST)
24-HOUR SIGNIFICANT LOCAL INSURED LOSS POTENTIAL: MEDIUM

DISCUSSION
Tropical Cyclone Nathan, located approximately 355 kilometers (220 miles) northeast of Cairns, Australia, is currently tracking west at 11 kph (7 mph). Animated satellite imagery shows that Nathan has developed a more robust and consolidated structure with deep convective banding wrapping into the cloud system center, despite the pinhole eye becoming cloud filled. Furthermore, the system continues to show cooling cloud tops within the expanding central core, indicating continued intensification. A recent high resolution scan confirms the increased convection within the core and more intense convective banding along the northern periphery wrapping around the low level circulation center. The initial position is based on the aforementioned satellite images and also supported by the Willis Island radar loop with good confidence. The initial intensity has been notably increased by the JTWC, as the 1-minute sustained winds are now listed at 150 kph (90 mph).

Upper level atmospheric analysis indicates a very favorable environment with a point source anticyclone above Nathan that is providing radial outflow and low vertical wind shear. In addition, warm sea surface temperatures will continue to fuel further development as it tracks towards landfall. Nathan is tracking along the northern periphery of a building deep layer ridge of high pressure that is currently centered over central Australia. This ridge will continue to serve as the steering mechanism throughout the forecast period, supporting a west to west-northwestward track.

Favorable environmental conditions will persist, allowing Nathan to further intensify prior to making landfall over the Cape York Peninsula within the next 24 hours. The JTWC currently projects a 1-minute sustained wind landfall intensity of 185 kph (115 mph), which equals a Category 3 rating on the Saffir-Simpson Wind Scale. The cyclone will weaken as it tracks along the Cape York Peninsula due to land interaction. Continued favorable upper level conditions and very warm sea surface temperatures in the Gulf of Carpentaria will allow Nathan to re-intensify when it emerges back over water. The system is forecast to make a secondary landfall over Cape Arnhem and weaken once again due to land interaction. The forecast computer model guidance continues to be in good agreement on the track, lending to high confidence in the JTWC forecast.