January 25/26 Jimbo Back Surgery Storm

[yotaman]

3 hours ago, Snow dog said:

Is it possible that the last squal line will be so heavy that it will at least limit theability of the freezing rain to accumulate?

I always wondered what happen if it was 20 and a heavy downpour hit. Would it ice up immediately or run off?

[USCG RS]

40 minutes ago, yotaman said:

I always wondered what happen if it was 20 and a heavy downpour hit. Would it ice up immediately or run off?

The physics of this is both complicated and nuanced. 

For rain to freeze, it has to be super cooled. Heavy rain has less of a chance to cool. 

Heavy freezing rain has less time to contact other freezing surfaces, which can lead to a run off thus making it accumulate less quickly, especially on elevated surfaces such as trees and power lines. 

Each rain drop also releases a touch of latent heat which can take longer to accrue. It also can warm the surrounding area ever so slightly. 

That withstanding, heavy ZR falling into the 20s with a light accreation already in place ovverules most of the potential negation of other factors. 

So if this line brings a good amount of QPF, it will accumulate, and quite a bit. Quickly as well.