Wednesday, February 25, 2015

Pattern shift ahead

Beginning this week, the mean trough position will shift west.  To date the trough has been centered over eastern North America.  Over the next couple weeks, that will shift to the center of the continent.  That will allow southern branch systems (Colorado lows) to affect the eastern side of the trough, ie Ontario.   Sunday will see the first of these systems affecting Ontario with Ottawa catching the northern edge per current model output.  The bigger deal, again according to the models, is the system on Wednesday, currently predicted to give us 20-30 cms of snow, possibly mixed with ice rain, a messy situation.

Stay tuned.

Tuesday, February 24, 2015

Thursday, February 19, 2015

And its gone...

Again in unison, the models have backed off the weekend for us, moving it south and weaker.   The fact that all models showed the back and forth shift leads me to believe that there was something about the initial conditions dataset yesterday that caused the shift.  That has been corrected and now all models are putting the majority of the snow well south of us.
I am beginning to despair that Ottawa will get any major snow event this season.  Yet hope remains: March in like a lion...

Wednesday, February 18, 2015

Interesting development in the models

As you may remember, a couple days ago the Euro was dumping us with snow this coming weekend.  In following runs it was a lot less enthusiastic and more south, coming in line with other models.

However in the latest runs of the GFS, Euro, NG, and Canadian, the track has moved north.  The Canadian so much so that it shows the main band of snow to our north and the Ottawa area has a change over to rain.   Now I don't think that will happen.  I think the Euro and GFS will be more correct with the storm track just south of the lakes, giving us a 10-15 cm dump on Sunday.

Look for forecasts for the weekend to change later this afternoon once the models are processed into the forecast.

Coldest part of the planet..

Is us...relative to average that is.

Thursday, February 12, 2015

Quick post from the bus..

Cold coming gangbusters.
A clipper originally predicted to go south of us will give us a glancing blow on Saturday.  The US models are more north on the track than the Euro and as such, giving us more snow.   So as of now, we could get anywhere between 2 and 10 cms.   This clipper will intensify of the coast and bomb the maritimes.
Chance of even colder air in the 7-10 day period.
A system coming from the south may make things interesting late next week too.

Monday, February 9, 2015

Even I am starting to feel sorry for the Maritimes...

Predicted snowfall over the next ten days...on top of the feet of snow they already have.   The weak clippers that we get intensify up into big storms once they hit the Gulf stream.