GFA and icing

[alex.proulx]

Hello,
I am a PPL slowly working toward my CPL, trying to build hours in a C172 when I can and I have a question about icing forecast in Graphic Area Forecast and about my understandings of icing in general.

Since I work during the days Im trying to fly at night but with the cold season new in place in Quebec I find myself in a difficult place icing wise.
I am constantly seeing icing forecasted on the GFA even on a clear night.

Take for exemple these 2 GFAs for : 0000Z 12.11.2017

https://imgur.com/a/8JTbY

gfa icing & turb 08.11.2017.PNG (156.48 KiB) Viewed 1128 times

https://imgur.com/a/1WZKY

gfa clds&wx 08.11.2017.PNG (147.78 KiB) Viewed 1128 times

https://imgur.com/a/1jPN4

metar.PNG (10.95 KiB) Viewed 1128 times

My first tough was cool, seems like a good night to fly but when i saw the icing and turb GFA I canceled the flight.

A pilot told me that as long as I stay out of the cloud, there wouldnt be any danger.
If I were to fly at lets say 3500ft, would I be okay in this situation ?
Do i really need to be in the clouds to catch icing when mdt mixed icing is forecasted like in this situation

Maybe Im at the point in my journey where Im scared of everything hahah

Thanks a lot for your help and input on that situation

[CpnCrunch]

It looks like Montreal is at the edge of the icing area...the GFA is showing broken at 3000 over the whole area, which is presumably why the icing chart is showing mixed icing from 3000ft, but right now there wouldn't be any icing there because it's clear. Even if the clouds do move in, you should be fine under the clouds as long as it's not snowing or raining. However it looks like it would be a bad idea to get too close to the low, as the weather will gradually get worse, so I wouldn't want to go to far to the NW.

My main concern flying at night is fog or ice fog forming on the ground.

[final28]

In addition to the information on the GFA I pay a lot of attention to temperature dewpoint spreads. The smaller it is the higher the likelihood of visible moisture in the air or of frost forming, depending on temperature.

[Blackdog0301]

I would probably go fly if I had a similar GFA to this. However, I wouldn’t fly at 3500. Why? Because the cloud bases are as low as 3000. Your friend is right that as long as you stay out of cloud, you won’t pick up icing. But you can’t always see cloud at night. You won’t know it’s there until you’re in it. So for that reason, I’d pick something lower such as 2500.

Just keep in mind that you don’t just pick up icing if you are in cloud. Any visible moisture could ice you up. Fog, mist, rain, wet snow