Back in December we saw warming in the stratosphere develop in the western arctic and Alaska.
By the holiday it enveloped northwest North America and the western arctic and had opened us up to invasiions of arctic air.
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It cooled again at 30mb signalling the January thaw
But see in 15 days how the models show it is repeating signaling the start of the SSW midwinter version.
See in the polar height time section the warmth in the polar atmosphere in December. See the cooling high up that peeked around the New year.
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See the follow up time series of 30mb temperature anomalies. The North American warming built to the south and faded but notice it is reloading in the Pacific.
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Another low solar east QBO winter (2007/08) saw that cold 30mb 65N-90N give way to Sudden Stratospheric Warming in January (it tends to come earlier in East QBO winters). Notice the warming can be 40C!
The sequence this year featured some warming (mainly West arctic and North America) that faded but is returning. Notice above how it pulses.
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Ok what does this mean? It means the January thaw will continue though as models show somewhat erratically but by the end of January we should be back into a wintry pattern and high latitude blocking. The February/March Pioneer forecast had this.
