Snowstorms

A whole lot of zzz's for the first week of December.

Relatively the same here at YYZ. However, I give a bit of a range and therefore consider "near normal" as a metric too. Trends and the overall pattern seems to favour a warm December. Although, I don't think it will be a blowtorch like 2011-12 or 2015. As it stands a mix between 2014 and 2018 seems likely. Both of which were +ENSO years. Colder December's are more common in La Nina's.

Quite the model battle going on right now for tomorrow's storm. Practically all 12z runs this afternoon have the GTA getting 4-8" tomorrow. Euro going all out with 8-12" . Latest HRRR has more SLT/PL than snow and keeps the GTA to within 2-4". I'm still skeptical as to how much snow falls tomorrow. How quickly we transition over to snow will depend how much the GTA will get. Niagara/Buffalo area will likely get a mix between FZRA and PL.

Not surprising. This entire decade for the most part has had warm December's with the exception of 2010, 2013, and 2017. This year is no different! There's a good chance we see a north pacific jet extension by the 2nd of week of December which will likely flood the nation with warm Pacific air. Now whether that continues till Christmas or beyond, remains to be seen.

Wow! That's alot of precipitation. 2008 is YYZ's wettest year as well, but we only got 41.3" that year. Quite the contrast given the relatively short distance between Chicago and Toronto. It's also crazy how 4 out of the top 5 have occurred in the last 11 years.

Looking like a wintry mess with a mixed bag of precipitation across Southern Ontario into Western New York this weekend. From London up until Hamilton and eastward towards Buffalo/Niagara, there could be a decent amount of ice accretion, with upwards of 0.30-0.40". Freezing rain seems more likely given the layer of warmth at 700 and 850mb. The GTA is far more tricker. It seems to be riding along the thin layer of warmth at 700mb with subfreezing surface temperatures. This would likely imply a sleet changing to snow type of event. Now how quickly that transition happens and whether any deformation band sets up will depend how much snow falls. As of now I'm leaning towards 2-3", but this is a tricky forecast. P.S. Happy Thanksgiving to my fellow Americans!

+ENSO and +IOD forcing playing a role in that. As well, models are hinting at the MJO trekking its way into phases 2-3 near mid-December which translates to a warmer pattern for us. Going to have to see if the upcoming -NAO/AO can hold on a bit longer. In recent years, Atlantic blocking has been abysmal so it wouldn't surprise me if it breaks down quickly. Regardless, the cooler anomalies in the first week of December won't be anything insane. Without proper blocking, it'll most likely be transient cold.

It was 6.9F this morning at YYZ making it the third coldest November low on record. Surrounding suburbs in the GTA were below 5F.

With the amount of controversy and criticism EC receives for YYZ's snow measuring techniques, this isn't surprising. I'd assume it has something to do with a lack of funding. But even then, Windsor is a major city in Ontario and this is unacceptable.

YYZ recorded 5.3" beating the previous record of 1.1" set back in 1983, haha. A general 5-7" fell across the GTA. I personally recorded 6.0". With a low of ~16.3F this morning, YYZ beat the previous record of 17.9F set back in 1937. We should beat tomorrows record of 14.7F set back in 1986 as well.

2.0" at YYZ as of 3pm. It will continue snowing till midnight.

Wouldn't that be like a top 5 snowstorm for Detroit in November if that did happen?

Temperature has dropped below freezing at YYZ. Should help allow the ground to cool for better accumulations when the storm arrives. Latest HRDPS sets up a pretty stout deformation band across the Niagara/Buffalo region. Could definitely see totals approaching 8-12" in this region.

Looking good for 3-5" across the GTA with amounts approaching 6-8" around Hamilton. Depending where the deformation zone sets up will determine what areas of the GTA see closer to 5". As of now it appears to be around the lake and further south towards Niagara. Let it snow!

Got down to ~21.5F last night at YYZ. Coldest low since March 23rd, lol.

Got about 1.3" here this morning. YYZ recorded ~1.0". First snowfall of the season.

I agree. 0z ECMWF had an interesting set-up.

The beginning of an epic LES outbreak, haha.