Dutch top 10 storms

According to the Royal Netherlands Meteorological Institute [KNMI or Koninklijk Nederlands Meteorologisch Instituut] the top ten storms that have affected the Netherlands in recent years are:

  1. January 25, 1990
  2. January 3, 1976
  3. April 2, 1973
  4. November 13, 1972
  5. November 27, 1983
  6. October 27, 2002
  7. February 26, 1990
  8. February 1, 1983
  9. December 24, 1977
  10. January 16, 1974

They don’t say how far they go back but I bet they stop before the 31st of January 1953. They do describe how they work out the magnitude of the storms in their list though, and rather gratifyingly they use the same simple method that I came up with! All that they do is add all the mean speeds from a network of their observing stations and take the average over the duration of the storm. The problem that I found with this method is – defining the exact start and end of a storm – i.e. when do you start and stop counting. Anyway I do seem to have SYNOP data for 9 out of the 10 storms (#4 occurred before the start of my SYNOP records) so here are plotted charts for each of them in what should be descending order:

Synops for Thu, 25 Jan 1990 at 1800 UTC

#1

Synops for Sat, 3 Jan 1976 at 0000 UTC

#2

Synops for Mon, 2 Apr 1973 at 1800 UTC

#3

Synops for Sun, 27 Nov 1983 at 0600 UTC

#5

Synops for Sun, 27 Oct 2002 at 1200 UTC

#6

Synops for Mon, 26 Feb 1990 at 1200 UTC

#7

Synops for Tue, 1 Feb 1983 at 1200 UTC

#8

Synops for Sat, 24 Dec 1977 at 1200 UTC

#9

Synops for Thu, 17 Jan 1974 at 0000 UTC

#10

As you can see they all seem to follow a very similar scenario. A low tracks across the central North Sea and on into Denmark or northern Germany, surface winds strengthen to gale force from the south or southwest, before veering to the west or northwest. It’s so different from the British Isles because we are an Island and are far more exposed than the Dutch are to storms from a variety of quarters.

Spotlight on Lusa

The weather station with the WMO designator 03037 has been in the news a lot this week. The station is situated on Lusa on the Isle of Skye, and I thought that I’d just look in a bit more detail at it. Here’s the big picture of where you can find Lusa.

03037 - Lusa (Skye) courtesy of Google Maps.

courtesy of Google Maps.

And here it is in a bit more detail…

03037 - Lusa (Skye)

courtesy of Google Maps.

The blue circle marks a 30 metre radius from the enclosure so this site could be just far enough way to be classified as class 1, but why the Met Office couldn’t have sited just up the road at the Broadford airstrip beats me, but there is obviously a very good reason why not. It’s probably called Lusa because of a small collection of houses close by, and the fact that it lies close to the little bay of Ob Lusa, which if you Google it will find is where you can find cold water coral (never say this site is just all about boring weather), I guess that Ob is Gaelic for bay.

Lusa (courtesy of Ordnance Survey and Bing Maps)

Lusa (courtesy of Ordnance Survey and Bing Maps)

It’s easy to see why this week in the easterly flow this site has been the warmest in the UK on at least two consecutive days, not only because of its location on the west coast of Scotland, but also because its downwind of the Northwest Highlands and the Kylerhea hills (just a few kilometres to the ESE), of which the largest is Sgùrr na Coinnich (739 metres). Interesting Glen Arroch lies to the southeast of Lusa which probably defines the predominant wind for the station. Anyway here’s the thermograph of hourly temperatures for the last two weeks for Lusa. On the 9th of May the 06-18 maximum was 26.7°C and yesterday (the 10th)  it was 25.6°C.

03037 Lusa (Skye) 18 AMSL 27 April-10 May 2016

03037 Lusa (Skye) 18 AMSL 27 April-10 May 2016

The wind, as you can see from the plotted hourly observations for the last few days, was crucial. At times the E’NE flow did veer a little more to the NE, and brought a reduction in the temperature, but for most of the time the gradient was strong enough to keep the sea breeze at bay and maintain a strong easterly component.

03037 Lusa (Skye) [08 May 2016 - 11 May 2016]

03037 Lusa (Skye) [08 May 2016 – 11 May 2016]

It’s interesting to note that in the cold spell, which occurred less than two weeks ago, there was a good snow cover on a lot of the western isles including Skye. You can see that the automatic weather station was having a bit of deciding on the exact weather type during the 28th of April. I cannot doubt that with these temperatures there was a fair amount of wet snow around on the morning of the 28th of April.

03037 Lusa (Skye) [27 Apr 2016 - 01 May 2016]

03037 Lusa (Skye) [27 Apr 2016 – 01 May 2016]

If it could snow on the island of Tiree I’m sure it did the same on a coastal site in Skye. Have a look at the following image and observations from Tiree, it’s not that unusual an occurrence but not that common in recent years.

Tiree on the morning of 28 April 2016 (courtesy of lifeontiree.wordpress.com)

Tiree on the morning of 28 April 2016 (courtesy of lifeontiree.wordpress.com)

03100 Tiree [27 Apr 2016 - 01 May 2016]

03100 Tiree [27 Apr 2016 – 01 May 2016]

And finally here are a couple of plotted charts to compare the contrast between the 28th of April and recent days.

Synops for Thu, 28 Apr 2016 at 0600 UTC

Synops for Thu, 28 Apr 2016 at 0600 UTC

Synops for Mon, 9 May 2016 at 1200 UTC

Synops for Mon, 9 May 2016 at 1200 UTC

The true measure of warmth

Maximum Temperature Anomaly [06-18] UTC on Monday, 9 May 2016

Maximum Temperature Anomaly [06-18] UTC on Monday, 9 May 2016

Yesterday, Lusa in Skye was not only the warmest place by actual temperature, it was also the warmest by anomaly – the difference between the actual maximum and the average maximum for the 9th of May – and that was a massive +13.0°C. In comparison the 27.1°C maximum on the previous day (8th) at Northolt in London was only +9.4°C above average.

There were some interesting variations around the Moray Firth yesterday as regards temperature too, the maximum at Lossiemouth was only 17.0°C but just along the coast a few miles further west the maximum was 25.2°C at Kinloss.

9 May 2016 - Maximum [06-18] anomalies

9 May 2016 – Maximum [06-18] anomalies

It’s all to do with sea breezes and whether you are exposed to one or not, in this case the gradient at Kinloss remained SE’ly, rather than E’NE as it was just along the coast beyond Burghead.

Synops for Mon, 9 May 2016 at 1500 UTC

Synops for Mon, 9 May 2016 at 1500 UTC

Sea Ice news

The following is a message from the NSIDC:

May 6, 2016

Daily sea ice extent updates resume with provisional data

NSIDC has obtained data from the DMSP F-18 satellite and is in the process of intercalibrating the F-18 data with F-17 data. Intercalibration addresses differences between the series of sensors, in order to provide a long-term, consistent sea ice record. While this work continues, we are displaying the uncalibrated F-18 data in the daily extent image. The daily time series graph shows F-17 data through March 31, and F-18 data from April 1 forward. Initial evaluation of the uncalibrated F-18 data indicates reasonable agreement with F-17, but the data should be considered provisional and quantitative comparisons with other data should not be done at this time.

Because these are provisional data, the Sea Ice Index has not been updated and continues to display only F-17 data through March 31. We expect to make the F-18 data available in Charctic soon.

For general information on the intercalibration of sensors, see the documentation for Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS Passive Microwave Data. This documentation will be updated when the intercalibration to F-18 is complete.

Likewise the Arctic and Antarctic comparison charts that I maintain have also not been updated since March 31.

Warmest 8th of May since 1878

Warmest Central England Temperature for the 8th of May

Warmest Central England Temperature for the 8th of May

Provisionally yesterday – Sunday the 8th of May 2016 – was the warmest 8th of May in Central England since at least 1878. The maximum temperature anomaly was +10°C warmer than the 1961-1990 long-term average for that day and was a full 2°C warmer than the previous warmest that occurred in 2008. The mean temperature was the highest since at least 1772 at 18.0°C and exceeded the previous highest mean of 1867 by 1.1°C. Quite an exceptionally warm day for early May.

03772 London Heathrow - United Kingdom 24 AMSL 2 May-8 May 2016

03772 London Heathrow – United Kingdom 24 AMSL 2 May-8 May 2016

It would have been nice to see Mercury but…

9 May 2016 1445 UTC (courtesy of NASA)

It would have been nice to see Mercury transiting across the face of the sun but typically for this part of the world the cloud wasn’t playing ball (again).

9 May 2016 1445 UTC (courtesy of NASA)

9 May 2016 1445 UTC (courtesy of NASA)

I’ve been a little busy but I’m back now…

work in progress

I did try to give up blogging for a number of weeks, but it’s proved to be impossible, so I have bitten the bullet, and invested in 12 months hosting with FVSHosting and repurchased my xmetman.com URL so that I can host my very own xmetman WordPress site.

I found that I just need an internet presence where I can express myself and display my creations on, even if no one reads the blogs that I write, it will still provide me with an outlet and a reason for all the weather and climate programs that I’ve written over the years.

There are a few advantages to owning your own blog rather than the free one from WordPress. For one thing you can embed your own JavaScript into your posts and pages, as well as installing from a much larger collection of widgets. So that’s why, at least for first few months, this site is strictly work-in-progress and a little on the experimental side. So please stick with me as I try out some of the new possibilities that are now opened to me, normal service will be restored eventually…