Welcome Back, Winter.

Simulated radar for the next 15 hours by a Rapid Refresh Model. Heaviest rain looks to move in around  12AM PST 

Simulated radar for the next 15 hours by a Rapid Refresh Model. Heaviest rain looks to move in around  12AM PST 

Last week, I proactively issued a very official Hydrometeor Alert for the City of Vancouver. Essentially a hydrometeor is anything that falls from the sky Ice, water, hail, sleet.

Anything at all.

Don't be alarmed, you'll see copious amounts of hydrometeors the next week. 

Frontal system after frontal system is set to pound the coast -- A current 990 mb low is set to cross northern Washington State this evening.

You know the drill.

Pressure drops off the coast have been significant, with 6+ millibar decreases observed the past 3 hours; consequently, the largest drops in North America this evening.

Pressure Drop..gif

Welcome back, winter. 

Now on how much rain to expect. 

The 18Z GFS model showing total precipitation accumulation for the next week. Yeah 10 inches or 250 mm isn't out of the question for Tofino, and the North Shore Mountains, and yes, Mount Washington. Next weekend there looks to be a heightened risk of some minor flooding, but it's still too far out to determine specifics details

The 18Z GFS model showing total precipitation accumulation for the next week. Yeah 10 inches or 250 mm isn't out of the question for Tofino, and the North Shore Mountains, and yes, Mount Washington. Next weekend there looks to be a heightened risk of some minor flooding, but it's still too far out to determine specifics details

Back on February 3rd, I predicted a Mount Washington re-opening this week, and looks like overnight tonight they'll finally have a enough snow to to fire up the lifts once again. 

But I did get one thing wrong.

I was too conservative in my snow amounts.

I think over the next two weeks over 200 cm of powder will fall to the slopes of Whistler, Mt. Washington, and a couple North Shore mountains, although freezing levels will be higher the further south you travel, so less amounts are likely there.

Speaking of freezing levels, it's an important parameter to look at for mountain snow. That zero degree isotherm is very critical in determining precipitation.

Where is the freezing level right now?

In Washington State the freezing level is higher, at nearly 1500 metres at QIL, but at Port Hardy (YZT) the most recent soundings are showing a freezing level below 1000 metres.

Excellent for mountain snow.

Here's the freezing level for the following 7 days for central Vancouver Island. Just use this as a rough guide, as I guarantee it will change.

This is the weather business after all.

Graph of the freezing level as predicted by the GFS for Mt. Washington for the next 7 days. Take home message: no large spikes above 1500 metres. So most (if not all) of the precipitation the next 7-10 days will fall in the form of snow

Graph of the freezing level as predicted by the GFS for Mt. Washington for the next 7 days. Take home message: no large spikes above 1500 metres. So most (if not all) of the precipitation the next 7-10 days will fall in the form of snow

Not too shabby.

I also won't be surprised if some wind warnings are issued this week, in response to the return of these deep pacific surface low pressure systems, which I'll talk about next post. 

#50ShadesofVan