High pressure at T240?
On Feb 24, 7:14*pm, Dawlish wrote:
On Feb 24, 5:25*pm, "Will Hand" wrote:
"Dawlish" wrote in message
....
On Feb 24, 4:59 pm, Nick wrote:
On Feb 24, 7:57 am, Dawlish wrote:
On Feb 23, 11:19 am, Dawlish wrote:
Both the gfs and (to a lesser extent) the ECM have pressure building
over the UK from about a week out. Nothing particularly warm on the
850 hpa temps, but as has been pointed out, we're approaching the
equinox and the stronger sun might well produce some reasonable
afternoon temperatures if skies were clear; light winds could further
accentuate the feel of more pleasant conditions.
See if that stays on the charts through today and especially if the
ECM follows the gfs, which has been keener on this scenario over the
last few runs.
Still signs of the establishment of high pressure over the UK by 10
days - ECM 00z coming around to that at T+240 now. The possible
buckling of the jet brings is closer to the UK this weekend and it
will probably bring some very wet weather with it for the south, but
then the gfs keeps the jet where it has been seeingly forever; well to
out south.
After the apocalyptic easterlies run yesterday evening from the gfs -
and there is still another colder burst shown on the gfs 00z before
the high might begin exert its influence - I'd need to see today's
runs showing high pressure before I'd be able to forecast its arrival
with reasonable confidence and with it a settling down of the weather;
not real spring-like a warming up as such, but a settling down. Over
the next week, or so, it just looks like more of the same, but wetter!
8(
Wetter than the last three days??? Get me a one-way ticket to northern
Scotland fast.... :-)
Nick- Hide quoted text -
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In some parts of the south Nick, for sure. As has been pointed out on
another thread, Sunday's low could be an interesting beastie! After
that, as you say, a settling, perhaps.
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Paul, the merest hint of a jet shift at T+384 (yes I know!).
I have been saying for a while now that this pattern will not be broken
without some external forcing which I reckon will come as the sun moves
north of the equator adding more heat into the NH system.
At tail end of GFS fantasy there was a WSW jet coming out of the States
which would begin to break the spell. So I will still go for Spring properly
arriving in the last week of March, which is when I will probably get my
first 10C this year!
What odds will you give me that I will get my *first* 10C of 2010 at Haytor
in the last week of March?
A chance to redeem your bookie's reputation :-)
Will
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It may Will, but I think the sun's movement will be coincidental. Last
year, the Feb cold was gone quickly and the warm-up didn't wait for
the equinox, or later. It's a fact that our climate warms in spring
compared to winter, but whether this relative northward movement of
the sun will be the cause of this winter finally relaxing its grip and
the jet moving northwards is moot. Ask the residents of Vancouver, or
Southern Greenland. *))
High pressure over the UK again on the 12z ECM and that's enough to
fulfil my criteria for a forecast:
**At T+240, on Saturday 6th March the weather in the UK will be
influenced by an area of high pressure and many areas will be
experiencing a pressure of 1020mb, or above. If skies clear, daytime
temperatures will feel very pleasant, in sunshine and light winds,
but nights may well be frosty where skies clear. Any precipitation
will be restricted to fronts dying into the high pressure, mainly on
coasts with onshore winds. The exact position of the high is always
difficult to predict at 10 days, but the anticyclone may well be
situated to our west, or NW.**
A quietening after the weather of the coming weekend. It will feel
springlike in some areas, but we're not looking wide swathes of the UK
experiencing 16C yet!- Hide quoted text -
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This one was just about spot on I feel. From 10 days ago, I'm happy
with the result from this forecast. There have been some changes along
the way, especially with a shortwave feature that was modelled, for a
while, to perhaps bring more unsettled conditions, with the potential
for snow, down the east coast this weekend, but for the models,
especially the gfs, to have shown pretty much exactly the same, 10
days ago, as what is shown on this morning's FAX charts is really very
good.
Whether what is being shown on the gfs today will be what is being
experienced in 10 days time is a very diferent proposition.
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