All eyes on York after worst September storm since 1981

Wednesday 26 September 2012, 15:02

Paul Hudson Paul Hudson

The deepest area of low pressure in September since 1981 has caused many of Yorkshire's rivers to burst their banks - although the rain was not quite intense enough to cause serious flooding of property like in the autumn of 2000.



Cumulatively since the rain started falling on Sunday evening, to when it stopped during the early hours of this morning, Ravensthorpe in Richmondshire has had the highest rainfall in the country with 131mm (over 5 inches).

At Leeming, 100mm (4 inches) of rain has been recorded in the same time period. This is almost double what would normally be expected in the whole of September (Average 52mm).

Furthermore, the station recorded its wettest September day, with 76mm falling in the 24hours to 10am on Tuesday morning. Weather data has been collected at the RAF station since 1945.

All eyes are now on the River Ouse catchment, whose tributaries are the Rivers Derwent, Aire, Don, Wharfe, Rother, Nidd, Swale, Ure and Foss, all of which have been high in the last 24 hours.

The Environment agency currently has 2112 properties on flood warning along the length of the Ouse catchment.

Current forecasts suggest the river will peak at midnight in York at no higher than 4.7 metres above normal. It is currently flowing at 4.5 metres above normal.

This would be higher than the peak in January 2008 of 4.5 metres above normal, but quite a bit lower than the record which was set in November 2000 of 5.4 metres above normal.

It will give comfort to the residents of York that during that record breaking river level, the main flood defences, including the Foss barrier, held.

Follow me on twitter @Hudsonweather

Comments

Jump to comments pagination
 
  • rate this
    0

    Comment number 1.

    The amount of rainfall has probably had an impact on the tourist economy this summer many events had reduced capacity all summer. October race event could do with some sunshine at the knavesmire

  • rate this
    0

    Comment number 2.

    The daily England & Wales rainfall on September 19th, 1981, was 25.04 mm, but I am not sure if that was related to the previous deepest area of low pressure mentioned above. There were four other days with over 10mm of rain but none of them were contiguous, either with the 19th or other day of over 10mm, so it must have been quite a stormy month.
    Sorry the figure of 43.23mm which I quoted in the previous thread, was actually on the 25th of August 1986, not September.

  • rate this
    0

    Comment number 3.

    Yet another freakish low bringing monumental rain. The most intense in Sept. since 1981. Not that long ago so nothing very unusual - I feel sure many sceptics will say.

    Maybe - if seen in isolation. But rather more unsettling in the context of exceptional rainfall and a long sequence of unusually disturbed weather starting in April. And this itself following on from an exceptional prolonged dry period. Don't forget the record heat/drought simultaneously occuring in America and elsewhere as well of course.

    Sceptics are hoping and trying to convince us that it must be caused (in some yet to be explained way) by the sun. Perhaps it is.

    On the other hand - what a coincidence it seems to be happening in line with warnings about man made climate change - imperfect models or not.

  • rate this
    0

    Comment number 4.

    Comparing one year to multi decadel warnings is probably unwise!

    'In the future plants in the UK will be affected by climate change in a number of ways:

    Increased carbon dioxide levels will increase rates of plant growth and perhaps development (bud burst, flowering and leaf fall)
    Changes in temperatures are expected to bring an earlier onset of growth in spring and a longer growing season
    Mild winters may reduce the yield of fruit trees, because colder temperatures are needed to break the buds
    Increased temperatures will aid the growth of more plants from warmer parts of the world
    Higher temperatures and decreased summer rainfall will cause stress, especially in plants with extensive, shallow, fibrous root systems
    Annual moisture content of soils is likely to decrease by 10-20% across the UK by the 2080s, with substantial reductions (of 20-50%) in soil moisture possible in the summer by the 2080s
    Fungal diseases will thrive with the wet winter conditions.'

    http://www.metoffice.gov.uk/climate-change/guide/impacts/horticulture

  • rate this
    0

    Comment number 5.

    #3. - jkiller56 wrote:
    "But rather more unsettling in the context of exceptional rainfall and a long sequence of unusually disturbed weather starting in April. And this itself following on from an exceptional prolonged dry period. Don't forget the record heat/drought simultaneously occuring in America and elsewhere as well of course."
    Whatever happened to "It's weather, not climate"! Oh, I'm sorry, that only applies when the weather appears to contradict "climate change" theory.

    "On the other hand - what a coincidence it seems to be happening in line with warnings about man made climate change - imperfect models or not."
    Yes, coincidence. Confirmation bias pure and simple.
    It is true that we appear to be going through a period of more "extreme" weather, but that is only part of the natural variability in weather. This only seems "extreme", compared to 20-50 years ago, which is as long as most people's memories go back. Rainfall was probably equally "extreme" in the 1920's and 1870's as it is now. The highest annual rainfall on record in Engalnd & Wales was 1285mm in 1872 and extreme rainfall is correlated with high annual rainfall.
    It is true that heavy rainfall is having more effect now but that is mainly due to increased areas of conurbation and the effect that has on drainage. There is more flooding, due to greater roof space, and more land covered in tarmac and concrete, which causes faster run-off into rivers and drainage systems. Large parts of the areas affected by recent flooding, didn't exist 50 years ago. There are simply MORE PEOPLE now to be affected by flooding.
    I agree that it would be easy to be seduced by recent weather into believing that it is something abnormal, if you are ignorant of past weather patterns.
    Some extracts from Whitaker's Almanac of 1897, referring to September 1896:
    "The weather was EXCESSIVELY wet and overcast. Sunshine was UNPRECEDENTLY deficient. Cyclonic storms passed over the kingdom rapidly, without SCARCELY ANY INTERMISSION, between the 22nd and the 27th, but with very DESTRUCTIVE VIOLENCE." There are also reports of rainfall figures of over 1 inch (25mm), in a number of locations during the month. And 1896 was actually in the middle of a period of relatively LOW annual rainfall - actually one of the lowest 10 year averages in the HadUKP series, so things would have been worse in the 1870's. The only reason I quote from this edition of WA, is that it is the oldest I have.

  • rate this
    0

    Comment number 6.

    #4. ukpahonta wrote:
    "Comparing one year to multi decadel warnings is probably unwise!"

    Of course, the official MO prediction was that "climate change" would cause lower summer rainfall and higher rainfall in the winter. Yet recently we had a "drought" caused by LOW winter rainfall, which was ended by HIGH summer rainfall.
    Of course to the biased, the fact that the MO predictions were WRONG is actually evidence of "climate chaos", not the incompetence of the MO.

    As the proponents of "climate change" used to keep telling us, "weather is NOT climate".

  • rate this
    0

    Comment number 7.

    jkiller - easy mistake to make, I'll sort it for you.

    The consensus are hoping and trying to convince us that it must be caused (in some yet to be explained way) by CO2. Perhaps it is.

  • rate this
    0

    Comment number 8.

    QV (and other data watcher/gatherers)
    Saw this yesterday. It may be 'old news' to you, but just in case you didn't already know . . .

    Randall Hoven posts: I knew NASA would occasionally update its estimates, even its historical estimates. I found that unsettling when I first heard about it. But I thought such re-estimates were rare, and transparent. There is absolutely no transparency here. If I had not kept a copy of the data taken off NASA’s web site two months ago, I would not have known it had changed.

    http://wattsupwiththat.com/2012/09/26/nasa-giss-caught-changing-past-data-again-violates-data-quality-act/#more-71520

    Steven Mosher explained: Nasa does not change the data of the past.
GISSTEMP is a computer program that estimates the global “average “temperature of the past and present. It relies on inputs made available by other sources, GHCN, and SCAR. There are ongoing projects to improve the coverage and quality of the incoming data sources. that means the input data can and will change on a monthly basis. Since the past is an estimate made relative to a 1951-1980 baseline period changes can and will ripple through the system. To put it simply. we don’t know the temperature of the past. We estimate it based on the data that is available. When that data changes, the estimate will change.

  • rate this
    0

    Comment number 9.

    The issue of concern is why did this low pressure just come up from the south wander over us and then do an about turn and head south again. In September 1981 the low probably headed off to Shetland and beyond. Hence the complete disparity in rainfall figures. Yes there was a kink in the jet stream for the umpteenth time this year. But why? I heard Paul Hudson on Radio Leeds expressing his concern that there does seem to be something wrong. Well we know the Arctic has about half the summer ice cover it had a mere 33 years ago so it is not functioning the same way. Think of the rotating tank experiment and the Rossby waves. You need a cold pole to make this work. I strongly suggest that greenhouse gas emissions have compromised the Arctic's ability to function in that way.

  • rate this
    0

    Comment number 10.

    9. Adrian Buckland wrote:

    "I strongly suggest that greenhouse gas emissions have compromised the Arctic's ability to function in that way."

    Arctic sea ice has set a new 'daily minimum extent' record every single day for the past 50 days, and has been below the previous record minimum extent level (set in 2007) for the past 34 consecutive days: http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

    It's looking probable that Arctic sea ice extent will stay below the level of the 2007 extent minimum right through September 2012. Since the end of the melt season on 16th September, Arctic temperatures have been well above average, as they were throughout much of last winter.

    The theory you allude to above, and previously discussed by Paul Hudson, is that the reduced temperature differential between Arctic and mid latitude air mass has caused the jetsream to slow and become more wayward. If this theory is right, then we may see some pretty bizarre and sustained weather across the Northern Hemisphere throughout the winter.

  • rate this
    0

    Comment number 11.

    5. QuaesoVeritas wrote:

    "Yes, coincidence. Confirmation bias pure and simple."

    When you consider the Arctic sea ice melt, continued ice sheet melt in Greenland and Antarctica, rising sea levels, increasing ocean heat content and record high land and coastal water temperatures across the US... etc.

    These coincidences are stacking up a bit, are they not?

  • rate this
    0

    Comment number 12.

    #11. - newdwr54 wrote:
    "These coincidences are stacking up a bit, are they not?"
    How many coincidences does there have to be before they are not coincidences?

  • rate this
    0

    Comment number 13.

    #10. - newdwr54 wrote:
    "If this theory is right, then we may see some pretty bizarre and sustained weather across the Northern Hemisphere throughout the winter."
    I agree that there will be "sustained weather" this winter.
    What is your definition of "bizarre weather"?

  • rate this
    0

    Comment number 14.

    Re 8: Steven Mosher's explanation is correct.

    It is striking that it takes one of the commenters to set the record straight. Shouldn't the blog owner, Anthony Watts, be the one educating his readers about how surface temperature records? Especially considering that's his area of interest.

    Instead we see him permitting an ignorance based attack to be hosted on his blog which wrongly attacks the science and scientists working on producing surface temperature records and spreads misinformation about them to the public.

    But perhaps that was the idea?

  • rate this
    0

    Comment number 15.

    #9. - Adrian Buckland wrote:
    "The issue of concern is why did this low pressure just come up from the south wander over us and then do an about turn and head south again. "
    I wonder why you think that such a thing needs an explanation.
    This is just the random movement of areas of different pressure in the atmosphere.
    No particular explanation is necessary.

  • rate this
    0

    Comment number 16.

    Re 11.
    I need more data to draw any conclusions. Fortunately (for this purpose) the arctic sea ice minimum will probably get even lower in coming years. I eagerly await to see what will happen *popcorn*, especially if it does reach zero.

  • rate this
    0

    Comment number 17.

    #10. - newdwr54 wrote:

    "It's looking probable that Arctic sea ice extent will stay below the level of the 2007 extent minimum right through September 2012."

    Would you like to have a little "notional" bet on that?

    I think it might just creep above in October, possibly temporarily.

  • rate this
    0

    Comment number 18.

    11: is not Antarctic sea ice at record or near record extent?

  • rate this
    0

    Comment number 19.

    @ 14 Quake

    "Re 8: Steven Mosher's explanation is correct."

    Really?

    "To put it simply. we don’t know the temperature of the past."

    Really?

  • rate this
    0

    Comment number 20.

    19: I hope that's a joke and you haven't quotemined that sentence out of context.

 

Page 1 of 4

This entry is now closed for comments

Share this page

More Posts

Previous
Yorkshire at risk from renewed flooding

Monday 24 September 2012, 15:19

Next
Regional and global climate update

Thursday 4 October 2012, 17:10

About this Blog

Hello, I’m Paul Hudson, weather presenter and climate correspondent for BBC Look North in Yorkshire and Lincolnshire. 

Blog Updates

Stay updated with the latest posts from the blog.

Subscribe using:

What are feeds?

About Paul

I worked as a forecaster with the Met Office for nearly 15 years locally and at the international unit, after graduating with first class honours in Geophysics and Planetary physics at the University of Newcastle upon Tyne in 1992. I then joined the BBC in October 2007, where I divide my time between forecasting and reporting on stories about climate change and its implications for people's everyday lives.

BBC Local

Get the latest news, sport, weather, travel and features from your local area.

Archive posts

For Paul's previous blogs, please click here: http://www.bbc.co.uk/blogs/paulhudson/archives.shtml