Large numbers of migrating bogong moths have returned to eastern New South Wales, creating a unique challenge for meteorologists who rely on weather radar to track rain, hail, and snow. The swarms are so dense that they are being picked up by radar equipment, appearing on imagery as widespread precipitation even on nights when no rain reaches the ground.

This is not the first time the insects have interfered with weather tracking technology. Observers note that a similar incident occurred during the 2000 Sydney Olympic Games, when a massive swarm attracted to stadium lights was initially misidentified as a rain event. While the technology used for weather monitoring has advanced in the 26 years since, the density of the current moth migration remains sufficient to bamboozle modern radar systems.

Meteorologists are now actively distinguishing between actual weather patterns and the presence of these moths. The Guardian reports that the ABC has confirmed that many of the rain signatures appearing on radar imagery across Sydney and eastern New South Wales are entirely false, as ground-level observations confirm no moisture has fallen. The return of the bogong moth in such high volumes highlights the sensitivity of radar technology, which is designed to detect physical objects in the atmosphere but cannot inherently differentiate between water droplets and biological swarms.