4) Drizzle There are two problems with drizzle. First, the tiny drops have very low radar reflectivity. Second, drizzle usually occurs in a shallow layer close the ground, which can get filtered out with ground clutter.

Synoptic Warnings Strong wind: Wind speed of 20 to 33 knots inclusive. Storm-force wind: Wind speed of 48 to 63 knots inclusive. Hurricane-force wind: Wind speed of 64 knots or greater. Freezing spray: Ice build-up rate on marine infrastructure 0.7 centimetres per hour or faster.

The intensity of rain, snow, sleet, or hail is estimated based on color, where light blue represents light rain (or snow), and red/magenta indicates flooding rains and severe storms.

A phenomenon called “ducting” can cause the radar beam to be reflected toward the ground, showing non-existent precipitation. Ducting can occur in the early-morning hours if the surface temperature is cooler than the air aloft. Birds and bugs flying into the path of the radar beam may also produce false radar echoes.

Clutter or ground clutter is a common phenomenon that most radars experience. In the picture, clutter is in the red box and rain is shown in the yellow box. Radars send out a signal to detect small particles in the atmosphere. Most often we are looking for hydrometeors like rain, hail, and snow.

Any of a variety of processes or techniques to eliminate the effects of unwanted signals (clutter) in radar measurements. Clutter rejection most commonly refers to the filtering of the received signal to reject components that have specified phase or amplitude characteristics.

Clutter is the term used and includes ground returns, sea returns, weather, buildings, birds and insects.

Basic types of clutter are: Surface clutter: Echoes from the sea or land are surface clutter. Echoes from land masses are stationary and from the sea has movement and causes Doppler shift so can be removed using signal processing techniques. Volume clutter: Echoes from rain and chaff are volume clutter.