SEQ Severe Thunderstorm and Microburst at The Gap

Summary

Amongst the severe thunderstorms that affected Southeast Queensland on 16 November 2008 was a destructive "microburst" observed at The Gap. Wikipedia describes a microburst as "a very localized column of sinking air, producing damaging divergent and straight-line winds at the surface that are similar to but distinguishable from tornadoes which generally have convergent damage". Large hailstones were also observed at several locations.

Illustration of a microburst (from Wikipedia)	Diagram of microburst from NOAA

Radar Images

128km Brisbane(Mt Stapylton) Radar Loop 16/11/08, 11:18am - 6:54pm. Click image to open loop in new window	Doppler radar velocity image obtained from CP2 research facility at Redbank Plains. Red/yellow shades indicate flow away from the radar, blue shades indicate flow toward the radar. Areas of darker blue bounded by red are velocity folded returns (Nyquist velocity=27.2m/s) and indicate windspeeds of >100km/h . SAM=Samford, CBD=Brisbane Central Business District. Peak wind gust indicated ~176km/h near The Gap at 4:48pm . Click image for larger view.	Doppler radar velocity image obtained from CP2 research facility at Redbank Plains: Vertical cross section through area of maximum velocity near The Gap at 4:48pm. Click image for larger view.

Track

Convective activity first started south of the NSW border. The first storms to cross the border propagated in a northeasterly direction causing some damage at Wonglepong, Canungra and Mt Tamborine. This storm later slowed near the coast and interacted with another storm that had also crossed the border from NSW, forming a new storm that then moved northwards from around Redbank Plains toward The Gap and subsequently the Sunshine Coast.

Loop of Mt Stapylton 45 dBZ TITAN tracks (VIL threshold filtered) 11.22am - 6.58pm Click image to start loop in new window

Satellite Images

Images from MTSAT-1R satellite received and processed by Bureau of Meteorology courtesy of Japan Meteorological Agency.
MTSAT Satellite Image, 16/11/08, 4:30pm AEST (visible) Click to enlarge

Impact Details

A summary of damage caused by the severe thunderstorms of 16 November 2008 can be found at the Queensland Department of Emergency Services website .