Above-seasonal in Calgary, then Friday snow!

CALGARY -

Calgary is setting itself up directly in the "eye" of a deep trough, spurned by the deformation of the mid-latitude bomb cyclone that's presently blasting the west coast with damaging winds in the 100 km/h range.

As the core of that low pushes north and a high in the U.S. Midwest dominates the pattern east of us, these pieces are combing to generate a sweeping zone of uplift that will travel in a veritable column across the prairies. It will start in Saskatchewan and whipping into Manitoba Wednesday.

What does this all mean for us?

Believe it or not, sunshine and mild conditions follow. We enter the "belly" of this trough, with the weather-making elements working south and east of us. The low is replaced by a high-pressure ridge Thursday, which heralds another change.

Friday's forecast is looking cantankerous. The entry region of a high-pressure system can be part of the exit region of a low. That's where your inclement weather is often made. It's still early, but the preliminary outlook is for at least five centimetres of snow. I repeat – it's early. Often, these forecasts verify with reductions in the current picture, but it's too soon to make guarantees.

Also, the Trick-or-Treat forecast has returned to normal, after a brief showing of flurries, which have now condensed into Friday.

YOUR FIVE-DAY FORECAST

Today:

• Partly cloudy, wind SW 40 km/h gusts
• Daytime high: 14 C
• Evening: clear, low 0 C

Tuesday:

• Mainly sunny
• Daytime high: 11 C
• Evening: mainly clear, low 0 C

Wednesday:

• Sunny
• Daytime high: 10 C
• Evening: mainly clear, low 1 C

Thursday:

• Sunny
• Daytime high: 10 C
• Evening: mainly clear, low 1 C

Friday:

• Early rain becoming snow
• Daytime high: 11 C
• Evening: snow showers, low -6 C

Our pics of the day:

Trudy took these really neat photos of the frost formation on the roof of her car! It's amazing how the tiny curvatures in the surface can create such intricate patterns.

Then, Kevin (a different one – I'm not much for speaking in third-person) tracked a sunset over Weaselhead Flats for this pic!

Thanks for sending! You can submit your photos here, email me here, or tweet them over!