I was part of the Bureau of Meteorology's forecasting team for the 2000 Olympics. One story that didn't get out was how worried we were with our 'fine and beaut' forecast for the opening ceremony. We had gone hard and early with 'promising' great weather for that evening. 1/

2/ The closer we got to the day the more certain we were that a southerly wind change would move through Sydney early evening on the day. The experienced local forecasters said that if the change had a depth of over 1km there would be a chance of drizzle.

3/ The computer models indicated that the change would have a depth of 'about' 1km. We held firm with the forecast but we were worried. I worked the evening of the opening ceremony. Cloud came in with the change on dusk and in the dimming light the cloud looked dark.

4/ On the radar display we suddenly saw this increase in returns that is a typical signal of drizzle when seen by a weather radar. Internal alarms bells rang. Visions of being lined up against a wall and shot started. We ran to the windows of our building and looked outside...

5/ Clouds were dark but we couldn't see any drizzle falling, roads were dry. We rang other staff driving home from work and asked if they could see any drizzle. We looked on the TV and the start of the opening ceremony. Nada, nothing.

6/ Then someone noticed on the TV a Bogong moth land on the opera singer's dress at the opening ceremony. Click. What we were seeing on the radar was swarms of Bogong moths flying through the air after dark. Swarms of insects look a lot like drizzle on the weather radar. Phew!