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SO MUCH WEATHER...

Here'e something that I think is quite remarkable. It's the phase history of the AO (Arctic Oscillation) going back to November. What I want you to notice is the period mi-December through the present. Not a single time did the AO get into the negative phase over the 3 month period (and still counting).

Why is that important? Because the positive AO indicates a westerly (zonal)jet stream flow across Canada, This persistent, powerful, and fast pattern does not allow strong or prolonged pushes of cold air to dig into the Midwest. It's no coincidence that temperatures the past 90 days have looked like this over North America. Some places in Canada have recorded 90 days departures as great as 12 degrees. That is massive and really quite rare.

We've done all right here too with departures of 4-6 degrees common since mid-December.

Where's the bitter cold been hiding? Up in good old Alaska where winter has been far from pleasant and even more harsh than it usually is.

So what happens if the AO decides to go negative. It's logical to assume there would be a reaction that involves colder temperatures. That's on the table as both the ensembles of the GFS and EURO are showing that potential. Here is what they are indicating the last 8-10 days of March.

That's a strong signal that cooler than normal temperatures may get back into the pattern on a regular basis the last week of March and perhaps the first week of April.

The odds increase even further when you look at the MJO. It's projected to go into the cold phases of 1, 2, and 3 between now and March 26th. (Follow the dotted green lines). It's roughly a week before it enters phase 1 and that ties in nicely with the AO dip and the time frame to watch for a downturn..

Here's the temperature analogs for phases 1, 2, and 3 in March. Phases 2 and 3 depict significantly below normal temperatures.

The EPO is another teleconnection to consider and it's also shown taking a pretty big hit as it moves into negative territory which is also know to produce cool temperatures by building a Pacific NW ridge. This is what the ensembles of the EURO and GFS depict over the next couple of weeks.

Another intriguing event is the warming that is taking place in the stratosphere. At 10mb, the very highest level of our atmosphere a rapid warm-up is shown the next 10 days. Here's the 10mb temperature departures today. Note the purple colors indicating a very cold concentrated vortex over the NW Arctic. That's been a regular feature and the driving force behind the positive AO.