Radar Challenges in the Treasure State

Posted at 9:17 AM, Nov 12, 2018
and last updated 2018-11-12 11:19:43-05

GREAT FALLS – Radar is an invaluable resource for weather forecasting.  In Montana, there are four radar sites, one at each National Weather Service office.  The National Weather Service in Great Falls covers an area spanning from the Rocky Mountain Front all the way to the Wyoming border, but radar doesn’t cover that area completely.

The mountainous terrain in Montana creates a challenge for forecasters.  At times, there will be snow falling in southwest Montana, but it won’t show on the radar, because the mountains block the signal from reaching the precipitation.

Additionally, the radar shoots the beam out straight. If there are low-hanging clouds far from the radar, the beam may pick up clear skies above the cloud top.  This is especially problematic in winter, when clouds tend to be lower in the atmosphere.

Because of this, forecasters rely on satellite imagery and ground reports to make sure that they’re forecasting with the most accurate information possible.