Blizzard in Boston

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Five to 10 inches of snow expected with wind gusts to near 50 mph.

More than 1,000 flights have been cancelled in the Northeast so far today.

People sometimes hear meteorologists talk about Dual-Polarization Radar. Here is an example of why it is valuable.  First, is the reflectivity data that you usually see on television:
While experienced radar meteorologists can make some inferences about precipitation type, the radar does not display or measure it.

One of the additional displays with D-P shows, explicitly, the different type of precipitation (7:05pm EST).

Remember, "sleet" is the little balls of ice that often bounce when they hit the ground. On your roof, they make a crackling sound.

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