Northerly Trough Transitions?

[Isolated Frost]

Hello.

I was wondering whether there were any patterns in which northerly winds, due to blocking to the west/north-west and a trough to the east/north-east, eventually turned to north-easterly or easterly winds, with the trough digging into europe allowing colder air from the continent into britain?

Thanks.

[Weather-history]

Hello.

I was wondering whether there were any patterns in which northerly winds, due to blocking to the west/north-west and a trough to the east/north-east, eventually turned to north-easterly or easterly winds, with the trough digging into europe allowing colder air from the continent into britain?

Thanks.

Late Feb 2005 is a well-known recent example

[Isolated Frost]

Late Feb 2005 is a well-known recent example

Just had a look on Wz and yep- right on the money... synoptics probably won't be as good this time around, but something similar at least would be great.

[Thundery wintry showers]

Here's a notable but very ancient one from January 1897:

http://www.wetterzentrale.de/pics/archive/ra/1897/Rrea00118970121.gif

http://www.wetterzentrale.de/pics/archive/ra/1897/Rrea00118970122.gif

http://www.wetterzentrale.de/pics/archive/ra/1897/Rrea00118970123.gif

[damianslaw]

Wasn't late November 2010 another good example?

[phil nw.]

I recall this in my favourite winter.A slight thaw then.

http://www.wetterzentrale.de/archive/ra/1963/Rrea00119630126.gif

http://www.wetterzentrale.de/archive/ra/1963/Rrea00119630128.gif

http://www.wetterzentrale.de/archive/ra/1963/Rrea00119630130.gif

http://www.wetterzentrale.de/archive/ra/1963/Rrea00119630201.gif

http://www.wetterzentrale.de/archive/ra/1963/Rrea00119630203.gif

Shows what`s possible if an Atlantic High retrogresses and we get amplitude in the flow.

[Thundery wintry showers]

Wasn't late November 2010 another good example?

It was a slower version of the same sort of progression- instead of having an individual trough slide down the North Sea we had a series of troughs, and thus it took three or four days for England and Wales to change from having a northerly airflow to having an east to north-easterly flow (although in Scotland it only took a couple of days).