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If Wishes made Weather

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  1. If Wishes made Weather
    Looks like both the average and gust wind speeds at our local MO station (Andrewsfield) are exceeding the MO predictions and are nearer the numbers forecast on XCWeather who I believe use GFS? Currently showing 38 mph average and 58 mph gusts. MO going for 30 and 53.
  2. If Wishes made Weather
    Wild night here. I have either just seen a bit of lightning, or its some power line arcing.
  3. If Wishes made Weather
    I would suggest that Stansted observations are a little higher than the MO forecast.
  4. If Wishes made Weather
    It’s interesting this area of higher winds that are being shown on the models for the area around the Wash, but also stretching down across the Gog-Magog hills and away more south-westerly towards the Severn. It’s visible on all of the charts I can see, but the MO are not showing higher windspeeds for places in this area. For example: Cambridge at 54mph, Andrewsfield at 54mph, St Neots 50mph, Ely 52 and so forth. All the models - even those giving ground speeds and not 10m speeds - are higher. Time will tell I suppose.
  5. If Wishes made Weather
    Yep - I’ve been concerned about this sort of ‘it’s only 5mph difference’ thing as when wind speeds are high, it represents a very significant difference in force. Also, at the macro level, when we have different models showing differences in wind-speeds of 15mph (55 to 70), then it shows how differently they apportion energy in the atmosphere.
  6. If Wishes made Weather
    It’s a generational thing. My lad sent me a link to this Dark predictions thing. I was slightly amused, but not at my lad who is in university studying maths …
  7. If Wishes made Weather
    As far as I can see, all models to one degree or another are showing this belt of stronger inland winds between the Severn and the Wash. Notable for the places that would be affected. Here the GFS showing up to 120kmh at 10m height. MO app at various places throughout this area showing 55mph ground level and appears to be the lowest. As noted by Snowshine above, the move to an amber alert at just be one of certainty in the predicted area.
  8. If Wishes made Weather
    I would suggest that the point of ‘impact’ is probably what concerns most people, rather than the measurable element of the weather itself. This makes the warning system a little complex. For me then there are two salient points. Firstly, the degree of deviation from what is normal for your particular area. So here in East Hertfordshire houses, garden fences and other built environment elements are less stable than a stone roofed and walled farmhouse in upland places. Hence, less windspeed here has more impact (as well as a greater population to be impacted than, say, Dartmoor). Secondly is the range of possible maximum gust speeds currently being forecast. The MO app for my location is the lowest at present stating 53 mph. Arpege suggests around 70 mph. The difference between the two matters because the energy in the 70 mph gust is more than twice (perhaps nearly three times) that of the 53 mph gust and the effect of this 17 mph difference would then be really substantial. I don’t recall seeing a 70 mph gust anywhere near here for the past 10 years or more - though if anyone has access to historical data it would be interesting to know.
  9. If Wishes made Weather
    Excelllent post. I note also that the Arpege is up there with the Icon at winds quite exceptional for inland southern parts:
  10. If Wishes made Weather
    As noted in an excellent detailed post by JordanS in the storm Isha thread, for our region, things have been a tad ‘upgraded’ for parts of our region. Generally, 10m wind gusts can be expected to be up to the 110kph / 68 mph mark. Here from the WRF: The MO showing slightly lower around the 100 kph / 62 mph mark as here: The Arpege though ups the anti by indicating 120 kph / 75 mph gusts inland: This difference between the two extremes here seems fairly small here at 13 mph, but it matters because there is something like a cubic relationship between wind speed and energy involved. So, even at the lower indicated speed here I would suggest that there will be quite significant impacts from this storm such as we haven’t seen for perhaps 10 years or more. At the upper end of the estimates, exceptional for inland southern UK.
  11. If Wishes made Weather
    The 0z suite confirms the MO position of the worsening of this storm. Looking like gusts of 75 mph inland are now reasonable to expect across swathes of the country including the south eastern quadrant. Add 10 mph to this for areas with altitude or costal or otherwise exposure. Don’t forget that the increase in energy that the energy in wind increases proportionally to its speed, but not at a 1 to 1 ratio, its more than that. Roughly, in terms of energy output on turbine blades wind speed has an approximately cubic relationship. For the purposes of ‘impact’ then when imagining the damage that a storm can do, a 5mph estimated increase in the speed of gusts from, say, 60 to 65 mph has a much greater effect than from 50 to 55 mph. Much more energy is involved now and I cannot imagine anything other than almost blanket amber warnings being issued soon.
  12. If Wishes made Weather
    18z GFS and all that, but this is a chart that we don’t see often - 80 mph for inland areas.
  13. If Wishes made Weather
    If the forecasts are about correct for what actually happens then this will have a high impact across inland and lowland areas in the south east as they only rarely see these sort of wind speeds. Overhead line pickup railways always fair badly - especially in built up areas - as rubbish that is lying around like plastic sheeting gets wrapped around the wires. Certainly on the rail line from here to London there is 10 miles or so where it passes through industrial and suburban north London where the trackside contains a constant stream of rubbish, fences are dilapidated and so forth. As the MO include impact in their warning system rather than just weather conditions I would expect an Amber warning for the south east at some point.
  14. If Wishes made Weather
    As far as I can see so far, the 12z suite continues the theme and strength of the winds. I wonder if the MO are keeping their powder dry by showing western areas only so far, and then expanding areas and severity of the warnings on Saturday or so?
  15. If Wishes made Weather
    … and worryingly, the GFS 6z suggests that the Yorks south will see winds which haven’t been seen for years inland. GFS 6z though so maybe not to be understood so much as a hard prediction, more like something that is possible. The other 6z offerings are similar to the 0z suites - 60 to 70 mph.
  16. If Wishes made Weather
    Icon and MetOffice continue to indicate 60 to 70 mph (100 - 110 kph) gusts in their raw output this morning for the first system Sunday to Monday.
  17. If Wishes made Weather
    Impressive looking system this for Sunday. The minimum 10m gust speeds being shown on the UKMO and GFS for any place in the UK except for an area around the Moray Firth is 60mph with many areas in excess of that. Rather than the strongest winds being reserved for an area of the southern quadrant around the core of the low pressure system, in this case the strong winds are being modelled right along the frontal line which is orientated NE-SW and will cross the country during a period of around 12 hours on Sunday with Northern Ireland being impacted first, and East Anglia and Kent last.
  18. If Wishes made Weather
    It looks like there is the possibility of a belt of 60(ish) mph gusts across the northern Home Counties early evening. For all of you in costal or more upland areas this would clearly be a regular occurrence, but in the areas highlighted by the amber warning and shown quite nicely on various models this is notable. Undoubtably there will be some disruption later on - weak fences, trees in waterlogged ground, bins, rubbish etc blowing around.
  19. If Wishes made Weather
    18z GFS puts anywhere in the south and east of the Wash to IoW in line for 100 kph gusts by 4am. Worse for coasts. That would be disruptive in a part of the country that does not normally see these sort of winds.
  20. If Wishes made Weather
    I think that there is something in this. To call something a disaster is to quantify it in purely human terms. Weather events can be determined ‘extreme’ when they are a certain position away from a norm for a given place - for example a wind speed >3x greater than average. This (meta and possibly quantum physics aside) will simply occur irrespective of humans observing or feeling any effect. It becomes a disaster when the human created environment is adversely affected or lives are damaged or lost.
  21. If Wishes made Weather
    It has just gone through here - like a very mild tornado.
  22. If Wishes made Weather
    Very impressive squall run through. Like a mild tornado.
  23. If Wishes made Weather
    I have just checked the fire department twitter ‘live’ feeds across the new red zone, and none of them except Bedfordshire have been updated with any wording at all overnight.
  24. If Wishes made Weather
    MetO model is now showing the ‘sting jet’ feature/possibility a little further south than other models. As Marky notes this matches the red alert zone:
  25. If Wishes made Weather
    I am right under that and not all that amused. Arome is showing a similar thing as the system pulls away: and the ICON is simply horrendous.
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