News of rumoured extreme low pressure. 940mb.
SWBKCB, basically the problem on take-off is that the aeroplane will try to weathercock into wind before it is travelling fast enough for the rudder to be effective - so the pilot will need to rely upon nosewheel steering early in the take-off roll - and that has limited authority as speed increases. The skill comes in transferring smoothly from nosewheel steering to rudder during the take-off roll.
For that reason, I always chose a full power take-off in strong crosswinds to minimise the time on the runway.
Another problem is that the into-wind wing will try to lift in a strong cross-wind; this can be worse in swept wing aeroplanes if the pilot needs to use a lot of rudder quickly in the downwind direction to counteract an unexpected gust causing weathercocking. So in conventional aircraft, a significant amount of into-wind control column deflexion is also needed, which will change as the aircraft acclerates.
All-in-all, there will be a fair bit of fancy footwork and skilled coordination going on during a crosswind take-off! Then, when the aeroplane becomes airborne, the pilot has to turn the aircaft into wind to maintain the required track as well as coping with turbulence before the autopilot can be safely engaged. Perhaps more of a challenge in conventional aircraft than in 'fly-by-wire' Airbus aircraft whose flight control computers assist the pilot extremely well as soon as the aircraft becomes airborne and the 'control law' blends from 'ground' to 'normal' flight in the first 5 seconds of flight.
However, the crosswind limit takes into account handling by an 'average' pilot - so you can rest assured that if the wind is less than the limit, conditions will be more demanding than on calm days, but not impossibly so.
I note that there are already differing opinions on various met websites regarding the threat posed by tomorrow's weather - fingers crossed that the lurid picture being painted by the BBC will turn out to be somewhat exaggerated!
For that reason, I always chose a full power take-off in strong crosswinds to minimise the time on the runway.
Another problem is that the into-wind wing will try to lift in a strong cross-wind; this can be worse in swept wing aeroplanes if the pilot needs to use a lot of rudder quickly in the downwind direction to counteract an unexpected gust causing weathercocking. So in conventional aircraft, a significant amount of into-wind control column deflexion is also needed, which will change as the aircraft acclerates.
All-in-all, there will be a fair bit of fancy footwork and skilled coordination going on during a crosswind take-off! Then, when the aeroplane becomes airborne, the pilot has to turn the aircaft into wind to maintain the required track as well as coping with turbulence before the autopilot can be safely engaged. Perhaps more of a challenge in conventional aircraft than in 'fly-by-wire' Airbus aircraft whose flight control computers assist the pilot extremely well as soon as the aircraft becomes airborne and the 'control law' blends from 'ground' to 'normal' flight in the first 5 seconds of flight.
However, the crosswind limit takes into account handling by an 'average' pilot - so you can rest assured that if the wind is less than the limit, conditions will be more demanding than on calm days, but not impossibly so.
I note that there are already differing opinions on various met websites regarding the threat posed by tomorrow's weather - fingers crossed that the lurid picture being painted by the BBC will turn out to be somewhat exaggerated!
Last edited by BEagle; 9th Mar 2008 at 10:40.
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TAF
TAF EGLL 090850Z 091019 24010KT 9999 SCT035 PROB30 TEMPO 1016 5000 +SHRA BKN020CB=
TAF AMD EGLL 090742Z 091212 25010KT 9999 SCT025 TEMPO 1219 7000 SHRA PROB30 TEMPO 1218 4000 +SHRA BKN014CB BECMG 2201 18010KT BECMG 0104 16022G35KT 7000 RA BKN014 TEMPO 0408 16035G55KT 4000 +RA BECMG 0710 21020G32KT 9999 NSW SCT025 TEMPO 0812 21028G48KT 4000 +RA PROB30 TEMPO 0812 TS BKN020CB=
Should make it sporty for the early morning arrivals!!!!
TAF EGLL 090850Z 091019 24010KT 9999 SCT035 PROB30 TEMPO 1016 5000 +SHRA BKN020CB=
TAF AMD EGLL 090742Z 091212 25010KT 9999 SCT025 TEMPO 1219 7000 SHRA PROB30 TEMPO 1218 4000 +SHRA BKN014CB BECMG 2201 18010KT BECMG 0104 16022G35KT 7000 RA BKN014 TEMPO 0408 16035G55KT 4000 +RA BECMG 0710 21020G32KT 9999 NSW SCT025 TEMPO 0812 21028G48KT 4000 +RA PROB30 TEMPO 0812 TS BKN020CB=
Should make it sporty for the early morning arrivals!!!!
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Well it will hit us tonight here on the western coast of Ireland. So I will give you breathless minute by minute reports of the drama and destruction. I'm looking forward to heading down to a point overlooking Galway bay at high tide. It is always a spectacle. It's an even better spectacle from inside a coffee shop on the prom.
It's a beautiful day here so far, mild and sunny, despite all the showers showing up on radar. We are just getting sprinkled occasionally.
The calm before the storm
I do think the British met office and the BBC weather people are overplaying it a bit. The old 'Don't worry there won't be a hurricane' comment is ingrained in the folk memory of the forecasters. So they make sure to build it up every time something more than a zephyr stirs the leaves on the trees.
In contrast the Irish met office are practically laid back about it. This is their latest:
That's it???? Becoming very wet and very windy? It's always like that round here.
It's a beautiful day here so far, mild and sunny, despite all the showers showing up on radar. We are just getting sprinkled occasionally.
The calm before the storm
I do think the British met office and the BBC weather people are overplaying it a bit. The old 'Don't worry there won't be a hurricane' comment is ingrained in the folk memory of the forecasters. So they make sure to build it up every time something more than a zephyr stirs the leaves on the trees.
In contrast the Irish met office are practically laid back about it. This is their latest:
Today
Most of the showers today will be over the western half of the country, with hail, thunder and sleet mixed in. Otherwise the day will be bright and fairly sunny, but rather cold and breezy with highest temperatuers of 7 to 9C.
Tonight
Becoming very wet and very windy this evening and tonight. Lowest temperatures of 4 to 7C.
Tomorrow
Further outbreaks of heavy rain tomorrow and still very windy.
Most of the showers today will be over the western half of the country, with hail, thunder and sleet mixed in. Otherwise the day will be bright and fairly sunny, but rather cold and breezy with highest temperatuers of 7 to 9C.
Tonight
Becoming very wet and very windy this evening and tonight. Lowest temperatures of 4 to 7C.
Tomorrow
Further outbreaks of heavy rain tomorrow and still very windy.
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What you have to remember here is that since the farse of 87 the british media and met office have always over-played any weather situation that is out of the norm, beit fog, snow, wind or rain.
The way they get away with this is that they tell joe public to batten down the hatches as on this occasion damaging winds will hit the U.K. When these damaging gusts hit and basically rattle a few crisp packets on the floor everydoby gives a big sigh of relief that nobody gets hurt and travel caos is kept to a minimum.
meanwhile anybody in the Industry has already looked at the tafs and realised how much of a over ramp this is...for example......
EGCC 091018Z 091818 21010KT 9999 FEW025 BECMG 2124 18020G30KT
BECMG 0003 15032G45KT TEMPO 0207 4000 RA BKN010 BECMG 0709
20012KT BECMG 1113 12015G25KT TEMPO 1118 3000 +SHRA BKN012CB
BECMG 1417 30015G25KT=
so gusting 45 kts for a 7 ish hour period......aint that bad...but saying that, it is across the runway and with rain forecast...might be interesting with the effect of olympic house at EGCC......but still nowhere near as bad as the hurricane like winds that the BBC are saying will relocate me from Manchester to Hull overnight !!!
The way they get away with this is that they tell joe public to batten down the hatches as on this occasion damaging winds will hit the U.K. When these damaging gusts hit and basically rattle a few crisp packets on the floor everydoby gives a big sigh of relief that nobody gets hurt and travel caos is kept to a minimum.
meanwhile anybody in the Industry has already looked at the tafs and realised how much of a over ramp this is...for example......
EGCC 091018Z 091818 21010KT 9999 FEW025 BECMG 2124 18020G30KT
BECMG 0003 15032G45KT TEMPO 0207 4000 RA BKN010 BECMG 0709
20012KT BECMG 1113 12015G25KT TEMPO 1118 3000 +SHRA BKN012CB
BECMG 1417 30015G25KT=
so gusting 45 kts for a 7 ish hour period......aint that bad...but saying that, it is across the runway and with rain forecast...might be interesting with the effect of olympic house at EGCC......but still nowhere near as bad as the hurricane like winds that the BBC are saying will relocate me from Manchester to Hull overnight !!!
Weather guessers are still weather guessers - they just make more inspired guesses these days!
Bring back beetles and fir cones!
I shall see whether the cows are lying down later today....
Bring back beetles and fir cones!
I shall see whether the cows are lying down later today....
More bang for your buck
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PKPF68-77 The problem is that every time we get a severe weather warning and all we get is a few gusts that do little harm the more likely we are to then start to ignore them as being the usual over the top hype so that when they really do mean it we all don't take any notice of it.
As I see the situation at the moment, it's the western part of the UK that is going to get strong winds, the Eastern side is just going to be a normal windy winters day.
In fact Wed appears to be worse for the East than Monday does.
As I see the situation at the moment, it's the western part of the UK that is going to get strong winds, the Eastern side is just going to be a normal windy winters day.
In fact Wed appears to be worse for the East than Monday does.
More bang for your buck
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G G check the EGKK 091818
For those who haven't found this site It's very useful, just hover the mouse over the arrow of interest and it gives current wind speed, left click and it gives winds for the next 5 days for that location.
http://www.xcweather.co.uk/
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presume this means no cancellations across Irish Sea?
Presume your professional opinion is that there will be no disruption for flights across the Irish Sea tomorrow. Minor event on in Cheltenham called the races!!! Should make it interesting for the rotorheads though!!
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Well, you can see it developing now in this animation (Sunday 6pm), rather impressive cyclogenesis,
http://www.sat24.com/frame.php?html=zoom&xas=87&yas=85
AFAIK this is the only close to realtime MSLP analysis chart for the N Atlantic - plotted metars, ship and buoy reports, (there's a time lag on the MO ones):
http://meteocentre.com/analyse/map.p...ng=en&map=AtlN
http://www.sat24.com/frame.php?html=zoom&xas=87&yas=85
AFAIK this is the only close to realtime MSLP analysis chart for the N Atlantic - plotted metars, ship and buoy reports, (there's a time lag on the MO ones):
http://meteocentre.com/analyse/map.p...ng=en&map=AtlN
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25 years ago based in Shetland the regional setting was 927 mb which was fun as the altimeters only wound down to 945 mb. Scatsa ATC used the old airforce QNE method to overcome this, (well Wally was ex Lancasters WW2). The water in Lerwick harbour was 1 metre higher than normal. Everything was so still it was eiry. Not to worry the next day the low began to fill and we were back to the normal............................gales.....lowest pressure I have come accross
OK , pundits ... so what is your forecast for the southern North Sea , tuesday evening , between Rotterdam and Hull . One is on the ferry to The Island , that night .
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all is revealed at
www.xcweather.co.uk/
No wind over 30 mph between midday and midnight, at a buoy off Harwich. Cant get into the Dutch end of your trip!
www.xcweather.co.uk/
No wind over 30 mph between midday and midnight, at a buoy off Harwich. Cant get into the Dutch end of your trip!