Saturday, 21 September 2013

North Pacific Pattern is Key

Couple important things we may want to keep an eye on over the next few months:

1. A batch of much warmer then normal SST's east of Japan favours stronger jet streaks over the north pacific. This sets up a +WPO pattern with zonal flow across Central/Eastern north america and a trough over Alaska/Pacific NW.
250mb Wind Speed and GPH forecast illustrate this pattern
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We need to see the GOA remain warmer then normal with cooling taking place across the bering sea and NW pacific. The ECMWF monthlies support this although the west coast cools some with the GOA warm pool shifting west.
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If we look at past torchy winters in the east we notice similar trends with a Ring of cold in the GOA and warm SST anomalies east of japan.
Sept 2011:
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The good news is, with the MJO currently over the W PAC, the tropics are responding over there with more recurving TC's helping to cool off the GOA/waters East of Japan. Obviously not the only factor to consider but something to keep an eye on...

A quick note on the QBO... we are quickly headed towards the +QBO peak and are expected to head into the westerly shear phase by winter which favours phases 7, 8 and 1 of the MJO.  This bodes well for winter weather lovers as it favours cold and snowy conditions over the eastern two thirds of north america.
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