On Thursday, March 20, 2014 8:51:24 PM UTC, Freddie wrote:
I said that the models showed that the *anticyclone* would retrogress, which is exactly what has happened.



No, it hasn't.



Yes it has. The anticyclone, which moved as far East as to be centred to our east,

then moved SW and is now centred in the mid Atlantic, south of the

Azores.

Erm that's not what happened.


Yes it was.

The high pressure, which was centred to our east before the weekend



No it wasn't - it was directly over us.



Yes it was. Look back over the charts and you'll see that the most easterly

point of its progressive journey left its centre to our east. Look

back at the charts.

I did look back over the charts - but only to double-check before I made my

assertions, as I follow them in real time too.


You have not looked carefully enough and I look at them on every run that I can.




pulled back through the weekend and early this week



No it didn't. The original high decayed from the north, allowing a



westerly flow to sink south over the UK. A new anticyclone moving from



west to east was in mid atlantic at the start of the week.





Pressure fell from the North, giving the appearance of a "decay"

(not sure exactly what you mean by that, word, Freddie) as the

high pulled back SW. After a brief incursion. the high

re-built and then clearly regressed SW again.

That's exactly how highs decay - by pressure falling.

Not from a limb!!




to sit where it currently is in the mid Atlantic



There isn't currently a high in mid Atlantic. There is a broad trough.



apologies from me. There is at our latitude. I was not specific

enough. Look to the south of the trough in mid-Atlantic. What

do you see?

That high is pretty much always there - it has been for the period

of the changes since you issued your forecast.


the high extended over us from the Azores settled over s, then to our east, then retrogressed, Freddie.

allowing the incursion of cooler, Atlantic air



This occurred when the westerly flow was sinking south over the UK at



the weekend.



We've had 20C in London on Monday and a 15C max every day in

some part of the UK. That is clearly not an incursion of

cold Atlantic air. I don't think we've had any hill snow

in that time - but we will have tomorrow and perhaps later

today.

I didn't say cooler - just a westerly flow, to differentiate our weather

from that of high pressure.

In that case, I accept that you did not say cooler.

and the change to a more progressive pattern, from a blocked pattern;



This occurred when the original block was eroded from the north by



strong cross-Atlantic westerlies - last weekend.



Yes. That's why I said that this retrogression began

"at the weekend", but, by today, it hasn't led

to the incursion of cold Atlantic air that the

charts suggested would have happened, 10 days

ago. Although pressure has fallen, winds are

between south-west and west, rather veering more

NW, as the charts suggested would have happened

by today.

But it wasn't a retrogression. It was a replacement

of high pressure with a westerly flow by a

non-retrogressive method.



I'm open to learning here

Good.

But, on the other hand, you appear not to be. It would help if you would look back more carefully at the charts for that period and provide some learning, if you can, instead of making simple assertions.

Freddie


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