As large-scale rising motion associated with the MJO moves back over the Maritime Continent and West Pacific region, it has helped to spawn a new tropical storm, Narelle, to the Northeast of Australia. The system is currently in its formative stages, but seems likely to intensify, potentially rapidly, as it moves west towards Queensland (Figure 1).
The upper-level environment looks favorable for intensification (Figure 2), and waters in the region are still warmer than usual as the La Niña event begins to decay, so there should be plenty of fuel for the TC as it moves off to the west.
After making landfall in Queensland, the TC will cross into the Gulf of Carpenteria, and continue to move west-southwest under the influence of an upper-level ridge (Figure 3). Upper level winds will continue to support intensification, so the TC should reintensify, perhaps quickly, depending on how much time it spends over water.
Regardless of intensification, the TC will likely bring lots of heavy rain to Queensland and the Northern Territory as it moves to the west (Figure 4).
The long-term fate is somewhat uncertain because the track is likely to be generally parallel to the coast of Australia. Some models have Narelle emerging back over the water to the Northwest of Australia, with time to reintensify before potentially making yet another landfall in Western Australia (Figure 5). Other models have the TC hugging the coast (Figure 6) and never getting a chance to significantly reintensify a 3rd time. Right now, Google DeepMind favors a scenario where the TC stays offshore long enough to intensify. It will be interesting to monitor this trend over time. A stronger cyclone initially will likely move more poleward (to the south), which might keep it inland for longer.
It is also worth noting that this TC and large-scale convective pulse will be associated with yet another westerly wind burst (WWB) over the West Pacific, which should help the atmosphere and ocean transition to El Niño over the next few months (Figure 7).
