Glidemet

Quick forecast for tomorrow (Friday): Good, but not great. Post-cold front with a ridge, but a isobar squeeze will give flying winds of 15-20kt from the west. Widespread good cumulus to around 4,500-5,000ft; best along the M4 corridor. Eastern areas cloudy and showery from that cold front, edging northeast out of East Anglia by mid-afternoon, but lingering on eastern coasts to the north.

Sea breeze convergence along much of the south coast and north Devon should be reachable, though watch for Bristol Channel air coming into Somerset later in the day.

By the way, thank you to everyone who’s voted in the polls or sent me comments.

Minor one: I’ve re-added the link to a simple table of useful webcams on the left.

Major one: RASP is going from strength-to-strength. Be sure to visit the homepage to learn about the latest additions to the RASP Viewer. Don’t forget about the Wind Tool either, which is still think is the best thing since sliced bread for hill sites.

Here’s your chance to say what you would like to see in competition weather briefings, and also what you want on those bits of paper everybody leaves on the floor afterwards.

First, the briefing itself.

You can chose up to five options, but try to chose fewer if you can—briefings shouldn’t last forever! On the other hand, I need to cater for everyone—not just those who have sat24.com on their smartphones.

I’ll be doing cross-sections for sure this year, but there’s more than one way of doing them. They can be for just the airfield, or one can make an attempt to “follow” the route, taking into account when and where the gaggles should be going, and what they’ll find there. My housemate found a wonderful old soaring weather book from the 1970s in our library with a section on competition forecasting, which had things like top-down charts of the task with weather symbols and cloud bases etc. pencilled in along the legs, which I rather liked. There were more ideas in there but I can’t remember them now! Will get the book out when I’m back…

RASP charts would be my favourite fields—surface sun and cumulus base, plus probably climb strength. But show those charts for two times, and that’s six charts of detailed information to display. Can people really take all, or even any, of that in? How much would they remember if I asked them again in ten minutes?

Forecast charts would be blow-ups of maps of temperture or wind from sites such as Wetterzentrale—again, same issues of data-overload.

Personally I’m leaning towards much simpler briefings, with perhaps a synoptic, a sounding, latest sat pics, and then a chat around the cross-section. But tell me what you think.

What should be in the hand-outs? Obviously there’s a limit to what organisers can afford to print, so we’re probably limited to a double-sided sheet of A4 here, and the vote limit is 4 options. Bear in mind that if you want more than two items on the hand-out, they’re going to be A5-sized images.

Here’s a separate poll about what I should be talking about—what happened (and why) for yesterday? An outlook for the rest of the competition? Or just the day? You can vote for everything here if you want, but again, think about if you really want all of that.

Finally, there’s probably things that you’d like to see but I’ve not thought of and made an option, so let me know in the comments if there’s anything you’d like added as a poll option.

Last post for the foreseeable future. It’s been fun to do soaring forecasting again, and useful practice ahead of forecasting for the Bicester Regionals and the Juniors later this summer! More on that in a second post…

Today (Thursday) sees a shield of muck over much of the Midlands and west which is slowly moving away/breaking up, but really all that moisture has done for those parts for the day, and the odd shower will pop up in the southern part of this cloud if the sun reaches the ground. This stuff formed over the seas to south and east and then moved through overnight—Heathrow had an overcast cloud deck at 700ft at one point.

For the rest of the day, we’re looking at an area northest of a line from Swindon to Liverpool moving west at 10kt, in which there should be cumulus to 4,000ft. I still wouldn’t venture far past Cambridge to the east, and watch out for dead areas beneath high-level cirrus. Bits of the southwest, beyond Exeter, should also be usable for local soaring but unlikely much more.

Friday now has a much stronger signal for showers, developing first from the southwest but probably affecting an area up to a line from Liverpool to London by afternoon. That said, they should be scattered and there’ll be soaring around them, but do be careful as there’s a distinct thunder risk, mainly over the Midlands. Further east, good cumulus to 4,000ft, but low and blue around the east coast again.

Saturday looks rather cloudy and showery over the Midlands, and Sunday sees the shower-risk area a bit further west. Central-to-eastern areas should be soarable both days.

Today (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…

It’s been so long I had to think how to do soaring forecast… Just had to bring some hope to the folks at Bidford, who don’t appear to have had a good start!

Tomorrow (Tuesday) sees the country divided into two: the good stuff, and the bad stuff. The good bit is a line from the Wash to the Solent, moving NW at 05kt. Here bases should be few/sct to 4,000ft. East of this line the inversion slopes to the sea going blue with a good sea breeze developing along eastern coasts. West, rather cloudy with bkn/ovc mid-level cloud and plenty of murk below. Showers, possibly heavy, pop up over most of the north and Midlands west.

Wednesday is when it starts cooking. A fair easterly sets in, about 15kt at height, and south a line from Norfolk to Cardigan Bay should be good cu with bases to 4,500-5,000ft, dropping to 3,500-4,000ft along the SW peninsula. North of Leeds, bases to 4,000ft west of the Pennines but rather lower to the east. The bit in between should stay largely blue. Big push of sea air into eastern coasts, with low grot along NE coasts.

Thursday, again a good day but with the risk of big showers pushing into southern parts late in the day, and also destabilisation in the southwest could see showers forming locally down there. Strong flying in the middle to west of the country beforehand though, away from that sea air along the east coast.