St Johns Rain Radar - 100km

Geographical Situation The radar is located on the coastal plain 35 km north-northwest of the Adelaide city centre. The main topographic feature of the region is the Mount Lofty Ranges, running roughly north to south from Burra to Cape Jervis. Shallow rain showers or drizzle beyond the ranges, particularly to the east and southeast, can be obscured from the radar's view. Otherwise, coverage is only limited by the distance from the radar, and the curvature of the earth. Meteorological Aspects Rain bearing weather systems usually approach Adelaide from the western half of the skyline, predominantly from the southwest through to the north. The Buckland Park radar is ideally situated to detect and track these systems. While the Mount Lofty Ranges may obscure the radar's view of shallow rain showers or drizzle on the eastern side of the Mount Lofty Ranges, heavy rain and thunderstorms in this area can be easily detected. Non-meteorological echoes In most cases, processing of the radar signal removes permanent echoes caused by hills, buildings and other solid objects, but sometimes a few slip through. These show up as small, stationary patches of light rain, mostly along the higher ground of the Mount Lofty Ranges. Under stable atmospheric conditions, particularly when low level temperature inversions are present, anomalous propagation may cause patches of echoes to appear along the eastern coastline of Yorke Peninsula, southern Gulf St Vincent, parts of Kangaroo Island and Fleurieu Peninsula. When the seas in Gulf St Vincent are very rough, some sea clutter may be visible in the sector to the west and southwest, out to about 30 km. This sea clutter tends to remain in the same area and therefore can be distinguished from rain echoes, which generally move with the wind. On occasions, the moving blades of wind turbines at the wind farms near Edithburgh on Yorke Peninsula, Snowtown and Waterloo to the north, and Cape Jervis on southern Fleurieu Peninsula may also be detected as isolated, stationary echoes. Example of sea clutter and typical weather pattern. <a