Weather radar: It matters where you look

Greetings with a summer post. A summer post on a ski blog? Whoda thunk it?

Last year, I did a post about weather forecasting that you should go back and read. The link’s to the right orĀ here.

I’m sitting here on a June afternoon with the sky full of thunderstorms. I thought it would be a great day to show the difference between the weather radar image focused on air traffic that EnviroCan generates, versus a commercial weather radar image targeting forecasting ground precipitation and hail forecasting, from WeatherModification.

Here’s EnviroCan’s.

EnviroCan

And here’s WeatherMods:

WeatherMod

 

Note they are a mere 2 minutes apart, so represent the same moment in time. WeatherMod’s pictures show info they need to suppress hail like cloud tops (in metres; that 11.4 sucker is a cloud 37,400′ tall), direction and speed (the red circles) so the display is busier; I turned on all the geographic reference features on the EnviroCan display, and clearly they offer better reference points than WeatherMod. But both show precip density on a colour scale.

Here’s some differences in the information they are showing:

  • WeatherMod show it to be raining in lots of places where Envirocan says it isn’t. Places like Cochrane, North Calgary, Airdrie, Bragg Creek, west of Olds, east of the Ghost. Lots of places. Many storm events (like thunderstorms) create precip at lower elevations, and EnviroCan doesn’t see it because it’s looking up, not down.
  • EnviroCan shows basically solid, constant density precipitation from Banff to the Kananasksis Lakes, with one small red spot around Mt. Lougheed. WeatherMod clearly shows numerous pockets of much greater precip intensity, as well as showing the one at Mt. Lougheed. We know this to be true in the winter because we know there are places (like Fortress and Peter Lougheed) that always get more snow than others (like Nakiska). Those microclimate variances show up at lower elevations than EnviroCan is looking.

All of this is also true in the winter. So when you look at the EnviroCan radar image to see where it’s snowing, take it with a grain of salt. EnviroCan sees what they want to see, and what they want to see isn’t necessarily what skiers want to see.

Hope your summer is going well. As the folks on Sunshine Social Media like to remind me, it’s only 147 days till opening day.