Before you read on, bear with me when I say this: This isn't going to be one of those overhype, scream-in-your-face posts practically forcing you to accept that winter is still coming, nor is it going to be an ultimate despair-based moan-and-groan tale of how the world will be a sauna for the rest of eternity.
No. This will be a fair-based, tell-it-like-it-is description of how the rest of winter will turn out to be.
FEBRUARY-MARCH
I know I have been proclaiming a cold and snowy February, but this is the first time I am now confident that there will be a cold and snowy pattern coming in.
This is my final prediction. I will not be changing it.
The Pacific North American pattern (PNA) has been in a positive phase for much of the winter- but not correctly matching up with other teleconnections (AO, NAO). As a result, we have not seen the cold and snow. A negative PNA sets up high pressure over the East and a trough in the West- something that has been very common this winter. However, the latest forecasts are calling for a +PNA to develop. A +PNA would result in the opposite of a -PNA.
As we have been seeing, the potential vorticity readings from the North Hemisphere way up by the Arctic Circle have been unstable recently. What I am seeing- and believe is true- is that this potential vorticity will start to be pushed down towards the US as a ridge of sorts sets up. The reason I believe a ridge will set up is because we have seen at least one ridge present in recent weeks up in the Arctic Circle- they just haven't been in proper places to get the storms into the US.
But it's not all in the PNA. It is very much a roll of the dice- certain teleconnections have to combine to make for a certain scenario. With the PNA going positive and the NAO/AO going negative, I think there is at least a chance we see cold and snow.
As for the AO/NAO, take a look at the past several weeks of observation.
We have affixed it with trends.
Just looking at the graphs easily shows how the pattern has changed in the last month. My belief is this: Now that the pattern has changed, I don't believe it will be changing back during February. Now that it has happened (albeit quietly), I just don't find it in the cards for the AO/NAO to spike back into positive territory, and the latest model forecasts even show that it will stay negative in the short term.
People have been trying to use analogues of years to compare to this one in order to figure out what the rest of winter will be like. I think that is just not a good technique this winter. As everyone reading this knows, an incredible amount of defined and undefined records have been set, from temperatures to how many times you shoveled your driveway. That's why I think people have let their guard down.
I have posted about how Tom Skilling (WGN Chicago Meteorologist) has said how winters with comparatively lower snow and warm temps have ended up back-loaded with cold and snow. That is one deal with analogues I am willing to believe. While everyone is comparing analogues with similar things already observed, I think that there is something different that is crucial to these forecasts.
Even though Tom Skilling posted that particular forecast for Chicago, Illinois alone, I think it applies to much of the rest of the East US.
My Thoughts
I believe February will be at least snowier. I think there is not enough evidence to prove otherwise, as we have already seen the pattern change. it has been shown in the AO/NAO and the PNA, among other things. The pattern should get stormier as the +PNA directs storms to a Panhandle Hooker flow and brings strong low pressure systems from the Plains to Great Lakes/Midwest and Ohio Valley.
The reason I focus on the PNA is because my confidence in the AO/NAO being negative (for at least the first week or two of February) is fairly high. A NAO/AO/PNA favorable combo may match up just right to make for a cold and snowy February.
If you have any local questions, you may ask them.
No. This will be a fair-based, tell-it-like-it-is description of how the rest of winter will turn out to be.
FEBRUARY-MARCH
I know I have been proclaiming a cold and snowy February, but this is the first time I am now confident that there will be a cold and snowy pattern coming in.
This is my final prediction. I will not be changing it.
The Pacific North American pattern (PNA) has been in a positive phase for much of the winter- but not correctly matching up with other teleconnections (AO, NAO). As a result, we have not seen the cold and snow. A negative PNA sets up high pressure over the East and a trough in the West- something that has been very common this winter. However, the latest forecasts are calling for a +PNA to develop. A +PNA would result in the opposite of a -PNA.
But it's not all in the PNA. It is very much a roll of the dice- certain teleconnections have to combine to make for a certain scenario. With the PNA going positive and the NAO/AO going negative, I think there is at least a chance we see cold and snow.
As for the AO/NAO, take a look at the past several weeks of observation.
Just looking at the graphs easily shows how the pattern has changed in the last month. My belief is this: Now that the pattern has changed, I don't believe it will be changing back during February. Now that it has happened (albeit quietly), I just don't find it in the cards for the AO/NAO to spike back into positive territory, and the latest model forecasts even show that it will stay negative in the short term.
People have been trying to use analogues of years to compare to this one in order to figure out what the rest of winter will be like. I think that is just not a good technique this winter. As everyone reading this knows, an incredible amount of defined and undefined records have been set, from temperatures to how many times you shoveled your driveway. That's why I think people have let their guard down.
I have posted about how Tom Skilling (WGN Chicago Meteorologist) has said how winters with comparatively lower snow and warm temps have ended up back-loaded with cold and snow. That is one deal with analogues I am willing to believe. While everyone is comparing analogues with similar things already observed, I think that there is something different that is crucial to these forecasts.
Even though Tom Skilling posted that particular forecast for Chicago, Illinois alone, I think it applies to much of the rest of the East US.
My Thoughts
I believe February will be at least snowier. I think there is not enough evidence to prove otherwise, as we have already seen the pattern change. it has been shown in the AO/NAO and the PNA, among other things. The pattern should get stormier as the +PNA directs storms to a Panhandle Hooker flow and brings strong low pressure systems from the Plains to Great Lakes/Midwest and Ohio Valley.
The reason I focus on the PNA is because my confidence in the AO/NAO being negative (for at least the first week or two of February) is fairly high. A NAO/AO/PNA favorable combo may match up just right to make for a cold and snowy February.
If you have any local questions, you may ask them.
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