Southeastern Australia Bushfires
After the start of the new year, hot, dry, and windy conditions were conducive to bushfires erupting over southeastern Australia. The fires were primarily observed in the state of Victoria, where the capital city of Melbourne resides. According to the broadcast outlet, 10-News Melbourne, approximately 400,000 hectares (or ~980,000 acres) were burned over the region, as of 14 January 2026. Refer to the social media link below that describes the bushfires and the impacts to the local communities.
The Japan Meteorological Agency’s Advanced Himawari Imager (AHI) captured the fires between 6-11 January 2026. The shortwave infrared imagery from AHI observes the fire hotspots (white and red pixels) at a 2-km spatial resolution, with a 10 minute temporal resolution. Notice, several fires can be spotted across the state of Victoria while multiple rounds of cloud cover and convection pass over the scene.
Himawari-9 AHI 3.9 um from 18Z, 6 January 2026 to 18Z, 11 January 2026
Zooming into the eastern portion of the state of Victoria, a daytime animation from the VIIRS Day Fire RGB shows the initial fire hot spots (red), the rapid fire spread and the corresponding burn scars (reddish brown) during the five-day period. The RGB is sensitive to fire hotspots, vegetation health (e.g., burn scars), and smoke (blue colors) where the RGB’s spectra contains a combination of the 3.7 um, 0.86 um, and the 0.64 um channels. The RGB exhibits a 375-m spatial resolution.
VIIRS Day Fire RGB daytime images from 6 January 2026 to 11 January 2026
During the same timeframe, nighttime visible imagery provided a view of the emitted city lights (individual white pixels or clusters), while also observing the emitted lights produced from the fires (bright, non-uniform white pixels). The VIIRS Near-Constant Contrast (NCC) animation below captures the spread of several fires, moving rapidly toward the south/southeast over the five-day period. Additionally, a distinct, nighttime fire smoke plume can be identified in the imagery on 9 January 2026. A large fire, located in the northeastern part of Victoria, produced a significant smoke plume on its southeast flank, which carried toward the coastline. Southwest of the fires, the emitted lights from Melbourne can be seen along the coastline.
VIIRS NCC nighttime images from 6 January 2026 to 11 January 2026
To help differentiate between the emitted lights from cities, to those from fires, users can compare the VIIRS NCC with the VIIRS shortwave infrared imagery. Refer to the imagery animation below. Emitted lights from fires have corresponding thermal hotspots (i.e., black pixels, seen in the VIIRS 3.7 um), while emitted lights that do not have a corresponding thermal signature in the shortwave infrared can be inferred as city or town lights.
VIIRS NCC and VIIRS 3.7 um (I-4) Band at 1533Z, 9 January 2026