Storm Doris

[size=83]Storm Doris left a tragic trail of devastation in its path after battering Britain with winds of almost 100mph, as one woman was confirmed dead and many more were left fighting for their lives. The 29-year-old woman was killed by rotten wood blown off a building by the swirling winds outside a Starbucks coffee shop in Wolverhampton city centre, prompting more than a dozen horrified onlookers to call 999. A girl was left with life-threatening injuries after a ceiling collapsed in a school sports hall in Milton Keynes, while in Aldgate, London, dramatic footage showed a woman receiving ...[/size]
http://hisz.rsoe.hu/alertmap/database/?pageid=event_desc&edis_id=ST-20170224-57259-GBR

Nasty one for sure :frowning: Daily Mail article with pictures.

Cheers Martyn, got back live again sometime between 7pm and 1am, i went to bed and woke at about 1 and it was back on

My max speed clocked in at 56.4mph @14:00, not so sure how much more my mast could handle at 6m unguyed… 8O 8)
It may have read a touch faster had it been at the 10m mark but without guylines i dare say the mast and equipment
would be in a carrier bag this morning :roll:

https://www.youtube.com/watch?v=_iqCeS-DwHc

I saw a comment from the UKMO yesterday which said that this storm was a result of explosive cyclogenesis, the same effect as happened in California.

Stuart

Yeah, i saw that too, mentioned it in my 1st post i think

Just for comparison, we saw 56mph (1207) and 60mph (somewhere around 1400 - I forget precisely) at two sites about a mile apart. Both open country and well-exposed but 3m height. So the 10m gust speeds would be estimated at 20-40% higher, depending on exactly how you choose to calculate the correction.

Open ground makes the world of difference, i am not overly sheltered here, the wind was coming from the west mostly, this
meant it came straight down between a row of houses and a row of bungalows, prob close to 100m between the rows and
not a great deal in the way, but what is in the way would have impeded the speed for sure, i am prob in a better than average
position for wind in a semi urban environment

With your setups being in open land, would there have been that much difference if they were at 10m opposed the the 3m?

As I understand it, yes. The detail is quite complicated and variable and depends on things like the ‘roughness’ of the terrain as well as - obviously - frictional effects of the ground. But here’s one paper I was looking at recently that provides some background as well as one approach to defining a correction formula:

If you look through the met literature then you’ll find many other similar papers written over the years, each often differing in detail but the general principle is always the same.

56.4 mph for me, 56.4 mph for you, & my all time record is also 56.4 mph 23/11/16, that looks a bit strange. A friend of mine just down the road in Diss recorded 67 mph, but that was using a R&D weather station, so there was not a lot of difference in the speed, but it just seems strange that three wind speed all the same.

teal.

I thought any height correction factor only applied to steady wind, all bets are off for gusts as they are caused by turbulent mixing the “potentially laminar-ish” flow anyway, bringing higher speed airflow down from higher to lower levels.

It does seem a tad strange, but then it could also confirm a true wind speed?

Poss. I’m not so sure, I’m now thinking something is not right.

teal.

Allowing for WD’s mph → knots → mph conversion that would be 56 mph from the VP2. It would be interesting to know what other values around that speed you see in your logs. My impression is that the VP2 doesn’t output all values of wind mph, but I’ve never had speeds that high to analyze.

In what way?

My leccy went off about 1pm I think but the logger caught it all



heres mine for yesterday if it helps Niko


New Text Document (2).txt (93.7 KB)

Single simple conversion of 56.4 mph is almost exactly 49 kts. Got any limits set?

Just checked, i have no limits set in the graph setup, anywhere else?

PS, before electric went off my OS recorded 2 at 52.9 so perhaps not a davis thing?

My all time record for wind here is 63.3 mph according to WD from my VP1 in 2007 so mine does at least go that high.

Stuart

Quite a large radius effected by Mrs D

http://weather.gladstonefamily.net/qchart/E9093?date=20170226&addnl=D7935&addnl=EGUL&addnl=EGUN&addnl=EGYM&addnl=D2843&addnl=D9422&addnl=E6611&addnl=E2699&addnl=E0058&addnl=D3371&Add+to+charts=Add+to+charts&.cgifields=addnl

WD has recorded 75 kts here with my Davis (86mph)