The latest ECMWF model forecast from Europe is showing the polar vortex (what makes the Arctic as cold as it is, not including the presence of a tundra landscape) sitting over Nova Scotia, Canada and the Canadian Maritimes. This solution would bring incredible cold and wind to the Maritimes, while a negative NAO rages, high pressure builds over the Arctic and a sliver of energy still remaining in Canada tries to build the vortex back up. What an incredible solution this would be if it verified.
But the truth is, models are horrible at handling pattern changes, so it's best we turn to ensemble forecasts.
The top image shows the ECMWF Ensemble prediction system, commonly called the ECMWF EPS (or just EPS for short) forecast at 10 days, and the GFS Ensembles (GEFS) are shown on the bottom, also valid 10 days out. These forecasts are showing 500 millibar height anomalies, where low pressure is shown in cool colors and high pressure in warm colors. Both ensemble sets agree on the polar vortex dropping down into Canada enough to bring the North US some serious cold, but nothing historic (nothing historic has been expected thus far- just serious, harsh cold). I feel like this will be a long-lasting event, with the sudden stratospheric warming's effects lasting for a couple weeks. This means, rather than one big cold shock, it appears possible that waves of cold will penetrate the nation, each wave spreading more and more cold around.
This is still a while away and the models remain without a consensus, so I will be updating you on the possibilities as this forecast time comes closer.
Andrew
But the truth is, models are horrible at handling pattern changes, so it's best we turn to ensemble forecasts.
The top image shows the ECMWF Ensemble prediction system, commonly called the ECMWF EPS (or just EPS for short) forecast at 10 days, and the GFS Ensembles (GEFS) are shown on the bottom, also valid 10 days out. These forecasts are showing 500 millibar height anomalies, where low pressure is shown in cool colors and high pressure in warm colors. Both ensemble sets agree on the polar vortex dropping down into Canada enough to bring the North US some serious cold, but nothing historic (nothing historic has been expected thus far- just serious, harsh cold). I feel like this will be a long-lasting event, with the sudden stratospheric warming's effects lasting for a couple weeks. This means, rather than one big cold shock, it appears possible that waves of cold will penetrate the nation, each wave spreading more and more cold around.
This is still a while away and the models remain without a consensus, so I will be updating you on the possibilities as this forecast time comes closer.
Andrew