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Was browsing through the modis (terra) near real-time subsets when I spotted something a little out of place on the thumbnail images between Australia and Antarctica. I then had to have a gander at at a larger pic to see what it was, then look at the aqua version, taken a little later to see if it was still there. I thought the contrast between the clear skies and the ring of cloud surrounding it was quite spectacular! A quick check for other satellite imagery on the BOM site, gave a IR image of the same area, showing the same circle, though not as clearly defined. And the explanation for it was a simple high pressure system! I realise it's not anywhere near as spectacular as some other shots (especially some of the storm chase pics!) but I find it impressive that a simple high pressure system can produce something that looks so impressive and slightly ominous too, like something punched a huge hole through the clouds!

[b]No this isn't an entry about the fall of social taboos! [/b][color=#000080]In fact I am talking about fahrenheit! This week parts of the north-east will experience temperatures in the mid 60s fahrenheit (17-19c). It doesn't sound impressive, but bear in mind temperatures have struggled to get past 12c during the last few weeks, and the brisk northerly winds have made it feel like February![/color] [color=#000080]Happily the weather improves this week, and although those of us on the east coast will see more cloud and lower temperatures, it will nontheless be a substantial improvement. What happens after this weeks warmth is anyones guess, but a return to the cold dross we have seen for most of May looks unlikely, thankfully.[/color] [color=#800000]On to sport, and a big congratulations to York City for their [url="http://www.bbc.co.uk/sport/0/football/18049175"]play-off win[/url] over Luton Town yesterday. York now return to the football league after an 8-year absence, and while you have to feel sorry for poor ol' Luton, it is terrific to see York back where they belong.[/color] [color=#800000]Plenty of golf action occured yesterday, with the booming Belgian Nicolas Colsaerts [url="http://www.usatoday.com/sports/golf/story/2012-05-20/volvo-world-match-play-championship-nicolas-colsaerts-beats-graeme-mcdowell/55093180/1"]beating[/url] Graeme McDowell in the Volvo Matchplay Final. Colsaerts takes home his biggest paycheque to date and moves to just outside the top 30 in the world rankings. Meanwhile, Jason Dufner [url="http://seattletimes.nwsource.com/html/golf/2018252094_golf21.html"]won[/url] the corresponding PGA Tour event in Americaland.[/color] [color=#006400]On a wildlife note, it has been more than a little disappointing on the insect front. I still haven't seen one damselfly or dragonfly adult yet, and although I did see a few butterflies around during late March and early April, the first (and in some cases only) generations on the wing have really [url="http://www.bbc.co.uk/nature/18101581"]suffered[/url] in the brutal weather. Happily, birdlife hasn't suffered too much, with plenty of swallows, swifts, house and sand martins about - great to see![/color] [b]That's all from me for now, thanks for reading[/b] [img]http://cdn.nwstatic.co.uk/forum//public/style_emoticons/default/dirol.gif[/img]

As time goes on I am fearing that the Model Output Discussion is going to degenerate into the usual summer fare, where the UK's weather is over-simplistically divided into two types: "settled" aka "good", and "unsettled" aka "bad". The main problem is that the desire for "settled" weather, for most people, is tied in with images of clear blue skies, warm sunshine by day, and evenings spent in the garden with the barbeque going. Of course, high pressure can bring such weather, and many of us will have memories of that phenomenal spell at the back end of March this year. [url="http://www.wetterzentrale.de/pics/archive/ra/2012/Rrea00120120326.gif"]http://www.wetterzen...00120120326.gif[/url] But in fact we only need to think back to the last third of July 2011 for an illustration of how we can be "bitten" by being too simplistic about this association. The forecast models showed a fairly sustained settled period with high pressure close by to the west, and the model output thread was buzzing with posts insisting that we were in for a lot of barbeque-type weather. In reality, though, for many of us the spell turned out dry and cloudy with a chilly northerly wind which left those BBQs gathering dust indoors. The problem is that for high pressure to bring us "BBQ weather", it really has to be in the right place. Here's one synoptic chart: [url="http://www.wetterzentrale.de/pics/archive/ra/1991/Rrea00119910515.gif"]http://www.wetterzen...00119910515.gif[/url] Let's be brutally honest, how many people would look at a chart like that and not think, "sustained settled spell- barbeque here we come"? In fact May 1991 was one of the dullest Mays on record as well as one of the driest and most settled. Another stark counterexample occurred during June 1988. This was an often-forgotten warm sunny month across much of Scotland (leading into that infamous washout July) but also an often-forgotten dry cloudy one across most parts of England, characterised by high pressure in the wrong place: [url="http://www.wetterzentrale.de/pics/archive/ra/1988/Rrea00119880610.gif"]http://www.wetterzen...00119880610.gif[/url] [url="http://www.wetterzentrale.de/pics/archive/ra/1988/Rrea00119880625.gif"]http://www.wetterzen...00119880625.gif[/url] Also, you don't actually need a sustained strong area of high pressure to bring this sort of "barbeque weather". The last week of June 2010, for instance, had a lot of this type of weather, but was only weakly anticyclonic: [url="http://www.wetterzentrale.de/pics/archive/ra/2010/Rrea00120100623.gif"]http://www.wetterzen...00120100623.gif[/url] And on relatively rare occasions, you don't even need any high pressure at all. I remember that in Tyneside (where in some summers, like last year's, we struggle to justify getting the BBQ out at all) I had a nice BBQ on the evening of the 4th July 1999: [url="http://www.wetterzentrale.de/pics/archive/ra/1999/Rrea00119990704.gif"]http://www.wetterzen...00119990704.gif[/url] ...and how many people would see a chart like that and think, "oh dear, dull wet unsettled dross"? That spell in early July 1999 turned out generally warm and sunny but with sharp thundery downpours, so as long as you timed your BBQ well you were okay. In fact it isn't all that unusual for the most "settled" spell of a month to end up being the cloudiest, if the unsettled weather is mainly bright and showery and the settled weather has high pressure in the wrong place. The dullest spell of this April so far was the relatively quiet one over Easter when high pressure (in the wrong place) ridged across from the west. It can even happen, more rarely, during a generally dull unsettled month (the dullest spell of August 2008, for many of us, was actually the relatively warm settled one near the end). Some of it probably stems from how we were brought up. I know that when I was at school, we were taught, "high pressure is settled (good) weather, low pressure is unsettled (bad) weather". I realise that, as a big fan of convective type weather, I am always going to be less enthusiastic than most others about sustained spells of high pressure (which have a habit of being convection-free). However, that consideration shouldn't affect the above analysis- I've deliberately looked at it from a "hoping for warm dry sunny BBQ weather" perspective, and shown how flawed/over-simplistic it is even from that perspective.