Wednesday morning
Back | HomeToday (Wednesday), west is the direction to go. We’re still in an easterly flow (about 15kt at height), so avoid eastern coasts and, well, the eastern half of the country which will, just like yesterday, see sea air reaching far inland. Generally anywhere west of the prime meridian will see cumulus to 4,500-5,000ft from midday until 6-7pm, with a fair chance of streeting. By the end of the period, the cumulus will be a bit tired and confined to west of 01W, with incursions of flat sea air further west in places, particularly along Thames Valley and across the Midlands.
The south coast sea breeze shouldn’t get too far in, in fact there could be decent convergence against that easterly gradient flow. The SW peninsula look likely to be swamped from the south, though north of Dartmoor should stay working until quite late.
Thursday should be practically a repeat of Wednesday but with added showers in the south west. Friday doesn’t look as strong, probably only good in a narrower strip from 00E—-02W. The weekend looks reasonable—-for those southwest of a line from Liverpool Bay to the Thames estuary. Sorry Seb!—-You should have picked a weekend I could come on :-p . Just remembered that the Varsity match is at Bicester this year…
Wednesday was not as forecast, for me and many others I listened to. After a strong climb near Leighton Buzzard at 1pm, I set off West in what looked to be a very good day, only to find 30% of clouds working with weak broken stuff, and long lines of weak narrow lift. I struggled back from Bicester (ok, motored back), took the strong climb still available at LB, and set off East in excellent conditions - reliable strong climbs to 5000ft bases. It turned out that I could have continued way past Gransden as it was still booming back here at 5pm. Interestingly, people at Corby were grumbling about 3500ft bases and weak conditions. Someone got it right because I met a large gaggle streaking eastwards near Bedford at 4:30.
Interesting, thank you for the feed back. The cumulus fields certainly extended further east than I thought they would, but comparing satpics for yesterday with RASP’s cu forecast suggest that RASP did a good job, at least for cumulus big enough to show up on satellite—-there’s always the chance of smaller stuff that doesn’t get picked up, so there most likely clouds further east than forecast, albeit small ones.
I personally reckoned that the sea air blowing in would make setting tasks into East Anglia too risky, but it certainly looks like going further east than I thought would have been OK. But I’m not sure how far past Gransden you could have got? Tibenham’s blog says “…but on the way back sea air had killed most lift east of Cambridge and the inversion was noticeably lower”, and Norwich’s METAR were reporting FEW020 most of the day before going BKN015 at 6pm. This was the reason why I said “west is best”, being able to get back again, but perhaps that the danger of suggesting tasking directions rather than just describing the weather and letting readers decide for themselves (I do, by and large, prefer to do the latter). Certainly it was working very well around Cambridge for most, if not all, of the day—-Cambridge’s METAR was FEW040 and higher all day.
I know of no way to forecast how well clouds are going to work—-if the temperature profile at low levels isn’t quite as unstable, or the surface temperature isn’t rising as much as hoped, climbs will be weaker. Wind breaks up thermals too of course, but I don’t think the wind was quite strong enough for that. Otherwise it’s pot luck, but surprising that it happened yesterday given the sun is at its strongest now.