Looking on the met office app just now at my location for tomorrow, the gust forecast averages three times the wind forecast, and this persists for the whole day. At a nearby location at times the gust prediction is 4x. Surely implausible. This sort of prediction tests my faith in the Met.
Oops! As ever, my proof reading let me down. My rather cryptic post was intended to refer to Meteociel - Observations des rafales de vent en Royaume-Uni en temps réel. Use this to look at Sligo a/p. The midnight observation is probably still there.
OK but I got the impression that some posters do not understand how gusts are formed.
I do not know whether or not the Met Office has changed its gust algorithm. I suspect that they have not and that what we have been seeing is a consequence of the very unstable weather conditions with deep convection. Strong gusts in vigorous convection occur in two ways. First, hail or heavy rain, literally, drags air down. That air spreads out as it hits the ground. The heavier the hail or rain, the stronger the gusts. A second mechanism is the overturning of air in vigorous convection. Air that was at 3 or 4 km above the earth is brought down with those speeds. In both cases, what happens at the surface is not greatly related to the pressure gradient, ie the wind strength at the surface between gusts. This is what happens in so-called “super cells” of “downbursts.”
I think that there is some hyperbole here. Even if the gust algorithms are wrong it is hardly a reason to junk the whole system.Yes there are alsoways some risks of gusts. But it is a waste of expensive super computers to have a next day forecast for weeks on end with wind forecast such as 6-8 mph gusting 20-26 mph.
As noted, I could print that on a laminated sheet of paper and use that as a daily forecast and be accurate 80% of the time. But equally no use to man or beast - certainly not a sailor considering whether to venture out.
My (imperfect) memory tells me that, for aviation and marine forecast purposes, gusts are defined as sudden increases in wind lasting 3 seconds.
Computer weather output, whether in GRIB format or provided in some form of app, is the basis for all marine, aviation and other forecasts issued for both our safety and to help us organise our lives. In the case of aviation, airlines worldwide use the same forecast information from either NOAA or the Met Office depending on the flight area. In the marine world use of forecasts is less prescriptive. However, wherever you are, there are forecasts issued under the GMDSS. The name says it all.
Not sure where these are from, but today is a bit exceptional - certainly pretty gusty in Tiree today - but exceptional enough to be a named storm Ashley
They won’t be interested. They are the experts and instead of listening to a valid point they will instead spend their time explaining that you don’t understand how weather forecasting works. They’ll explain that your narrow data set for a specific point is invalid (they’d do this regardless how large your dataset is).
I simply used Meteociel - Observations des rafales de vent en Royaume-Uni en temps réel and chose a few locations at random. Many gust/average speed ratios were not exceptional enough were large enough to make some assertions in earlier posts invalid. In other words, gust speeds exceeding twice the eversge wind are not rare.
How do you know that they did not happen? I can accept that you did not experience them.
I suggest that you you look at the Meteociel site or the XCWeather list of actuals.
I have given the link before. Meteociel - Observations des rafales de vent en Royaume-Uni en temps réel. You can try XCWeather as another source of actuals. The data are as reported from stations reporting to WMO standards and taken directly fro the WorldWideWesthrr channels.Not sure where these are from, but today is a bit exceptional - certainly pretty gusty in Tiree today - but exceptional enough to be a named storm Ashley
Bit different from the weeks in summer when this was first noticed.
Well, I do not know your background. Mine includes weather observing networks, instrumentation and observing standards. Instrumentation and definitions (including wind, of course) have evolved to meet user needs, including aviation as a main driver and definer of needs along with shipping in general, and leisure sailing in particular, as other important customers.
We are seeing clime change happening. Of that there is no doubt. Cleverer people than me were saying that well before I was and even longer before Trump displayed his abysmal lack of knowledge.
I fully believe that climate change is real and is being experienced daily by people whether they believe in it or not.
The majority fought strongly against that actually, climate change took a generation to be accepted by most experts, which is kind of what I said.
Even in Antarctica, where the effects of climate change are strongest, it was not possible to state with statistical certainty that the average annual temperature was increasing and that it was caused by climate change until the late 90s or early 2000s (not sure exactly when!). Pretty much all of us in the Antarctic business (so to speak) were pretty certain of it (I have two papers at least on the topic that indicated long-term change; colleagues published many more that pointed to changing climate - but not at the necessary level of statistical certainty) and we could certainly say that the temperature was rising, but because of the relatively short times series (we only had temperature records back to the 40s) it wasn't possible to say it couldn't happen by chance until the late 90s. As I say, we were all pretty much convinced of it on a variety of grounds, but nothing that we could say was outside the possible natural range. Even convincing anecdotal evidence is just that - anecdotal. Of course, as I worked for a government organization, we had to be conservative in our statements.
Maybe another way of looking at it is that it took a generation's worth of data to irrefutably show that there was a trend and not just randomness. I do question the implications of this, and your previous post (to which I responded) that all experts are only interested in preserving the status quo until retirement. That being the case, which generation of experts do we believe and which status quo do we choose to accept?
