On Jan 13, 8:30*am, Stephen Davenport wrote:
There is a link but it doesn't necessarily always manifest.

Two reads:

Tropospheric Precursors of Anomalous Northern Hemisphere Stratospheric
Polar Vortices
Chaim I. Garfinkel and Dennis L. Hartmannhttp://www.eps.jhu.edu/~cig4/GHetal10.pdf

The Life Cycle of the Northern Hemisphere Sudden Stratospheric
Warmings
Varqvut Limpasuvan, David W. J. Thompson, Dennis L. Hartmannhttp://www-k12.atmos.washington.edu/~dennis/Limpasuvan_etal_JClim_04.pdf

The polar vortex is certainly being displaced and disrupted by
stratospheric warming and cold cyclonicity in the troposphere will
ensue end of next week. Northern blocking is another matter, though,
and maybe people (not here) jump too quickly on the idea that any
stratospheric warming automatically means high latitude blocking and
subsequent frigid E-NE'lies for the UK. The EPV at 60N/10hPa might
need to be more poleward than it's been or is forecast for that. In my
opinion.

Stephen.



That's true. However the first paper does not deal with SSWs Stephen.
It is about tropspheric precursors of disruptions to the polar votex
and talks about ENSO and North Pacific teleconnections.

The second paper I've read several times, though other research
postdates it. It talks about disruption of the polar vortex, downward
propogation of warming and wind anomalies and the development of
easterly anomalies at 50-60 degrees north, but does not specify where
these could occur, or the probability of this sequence actually
occurring and changes reaching the surface i.e. there is no "will"
whatsoever in terms of affecting our weather in the UK.

It's what other, later, research shows too. This remains a minor event
- there are no easterly anomalies, or reversal of winds at the 10hpa
level - and forecasts are not for it developing into anything more.

http://wekuw.met.fu-berlin.de/~Aktue...w/wdiag/ts.php

A change in our weather is bound to happen, at some stage, after 6/7
weeks of continuous zonal weather and anyone making clear links
between any changes and events in the stratosphere is very shaky
ground and they have not grasped what the research clearly shows. Will
prophesied continuing cold last year and a "bitter" end to January on
the back of the development of a (minor but stronger) SSW. It simply
didn't happen, but he's making exactly the same links again and
expecting people to believe he knows the cause of any changes; changes
which haven't yet actually happened. *))