On Apr 5, 12:17 pm, Dawlish wrote:
On Apr 3, 12:01 pm, Weatherlawyer wrote:

On Apr 2, 7:35 am, Weatherlawyer wrote:

On Apr 2, 7:26 am, Weatherlawyer wrote:

On Apr 1, 12:50 pm, Weatherlawyer wrote:

There is an anticyclone now in almost exactly the same position the
low was in the other day.

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Could it be that it only takes a variation of 1mb for a high pressure
to be changed to a low pressure on the chart? The system has remained
in the same position and has altered it's characteristics marginally,
but its meteorological name has changed, as it has crossed that
arbitrary 1013mb, average atmospheric pressure, threshold?

Before I welcome you to the group I aught to warn you that there is a
tendency to besmirch anyone looking for answers on here.

Welcome to the group.

I have not really looked at the chart in any detail. They almost
never, ever change as quickly and as unexpectedly as they seem to be
doing in this spell. A spell usually runs the length of time it takes
for the moon to run 90 degrees. (No idea why, it is just.. so.)

An anticyclone runs clockwise IIRC and a cyclone runs the other way.
Looking down from the N Pole you would see the earth spinning from
Greenwich to what used to be New Orleans to Fiji to Calcutta to
Greenwich.

That is a cyclonic direction. Maybe it is why there is a tendency to
anticyclones in the Arctic. But going through the planet it would make
Antarctica tend to anticyclones wouldn't it? So it isn't that.

Of course with a weak set up the wind directions in reality can be
difficult to ascertain.
Fortunately one of us thinks he has discovered another tool in the
shed:
What do you make of this:

Update time = Sat Apr 5 11:00:01 UTC 2008

5.0 2008/04/04 13:30:15 44.625 148.035 52.0 KURIL ISLANDS
5.5 2008/04/04 04:03:03 -15.315 -172.850 47.0 SAMOA ISLANDS REGION

5.2 2008/04/01 01:31 20.3 122.0 35.0 BATAN ISLANDS REGION,
PHILIPPINES
5.1 2008/03/31 13:30 -2.8 101.0 50.4 SOUTHERN SUMATRA, INDONESIA
5.3 2008/03/30 22:12 0.13 98.2 50.8 NIAS REGION, INDONESIA

http://earthquake.usgs.gov/eqcenter/...quakes_big.php

The figures represent:
Magnitude; date; time; co-ordinates; depth and general location. The
last three represent when the Low was rather deep IIRC though I aught
to go and look at my collection to make sure.

Pity I am so lax that I won't.

When a Low lapses it is shown as wide apart bands of pressure lines.
They are spaced at 4 mb intervals. When there is no discernible air
mass there tends to be a no-man's-land between parcels of Lows and
Highs called a col.

I can't remember what pressures they tend to but it will be something
around 1005 to 1010 mb.