The Weather Channel - Radar News (2024)

FAQs

What does the grey dot mean on the weather channel radar? ›

Precipitation moving perpendicular to the radar beam (in a circle around the radar) will have a radial velocity of zero, and will be colored grey. The velocity is given in knots (10 knots = 11.5 mph).

Blue and green colors represent light-to-moderate rainfall. Yellow and orange colors show moderate-to-heavy precipitation, while red is very heavy rainfall and pink colors inside the red color represent hail of different sizes.

Warm colors (red) / positive values indicate wind moving away from the radar (along a radial). Cool colors (green) / negative values indicate wind moving toward the radar. Purple indicates “range folding”— where the radar cannot determine the radial velocity. Velocity image of a large-scale weather system.

They provide fine resolution measurements of reflectivity and velocity and multiple categories of analysis products. Data and information from these radars allow forecasters to look inside storms and infer wind speed and direction.

Purple denotes range-folding (RF), which is when the return from a prior pulse is detected during the listening period for the current pulse, and the radar is unable to determine the wind's velocity. Other radar systems commonly use this color scheme, but some may use different colors.

The colors are typically a spectrum. The greens indicate light or moderate rainfall. Yellow, orange, and red indicate moderate to heavy rainfall and can also indicate hail. Whites or blues mean snowfall and pink indicates freezing rain, sleet, or a wintry mix.

On a weather radar map, a tornado is usually indicated by a smaller area of red surrounded by a larger area of green. However, modern radar systems can also indicate debris balls, a sign of a tornado on the ground.

So, if you see a radar map using this scale, black would indicate “no echo” which basically means the radar did not get any measurement for the black areas of the map. Purple, on the other hand indicates intense echos were received by the radar and most likely very intense rain with large hail possible.

Red is typically a target moving away from the radar, while green is applied to targets moving toward the radar. The intensity of these colors determines its estimated speed.

dBZ. Nondimensional "unit" of radar reflectivity which represents a logarithmic power ratio (in decibels, or dB) with respect to radar reflectivity factor, Z. The value of Z is a function of the amount of radar beam energy that is backscattered by a target and detected as a signal (or echo).

What are the color codes for weather? ›

Weather Watch Box Colors

If precipitation is severe, watch boxes will also show up in addition to precipitation intensity. Red dashed = tornado watch. Red solid = tornado warning. Yellow dashed = severe thunderstorm watch. Yellow solid = severe thunderstorm warning.

Factors that determine the accuracy of a weather forecast include how far out the forecast is, the technology used, and the area's geography. In some places, the weather changes more rapidly than in others.

Radar technology is considered an active remote sensing system because it actively sends a microwave pulse and senses the energy reflected back. Doppler Radar, Scatterometers, and Radar Altimeters are examples of active remote sensing instruments that use microwave frequencies.

Weather stations are the backbone of all meteorology and forecasting.

If the blue dot isn't visible or is gray, Maps can't find your current location and shows you the last location you visited.

For example, if you notice the dots in a line, that could indicate the leading edge of a cold front! Meanwhile, if you see an increase in dots on the WatherRadar, that means a storm is intensifying. Therefore, if you are nearby, you should seek shelter!

The dot has been designed to indicate where the current temperature falls on the temperature scale for that day. If the high is predicted to be 42 degrees and the white dot is at the end, that is the warmest part of the day. The same indicator is present in the UV Index and the Sunset times.