Mild air returns to Deeside

After some pretty sharp frosts this last week, mild air has now returned to  the north of Scotland and particularly Deeside today, with temperatures getting  up to at least 12°C late this morning.

thermograph-for-03080-aboyne-00-utc-on-23-nov-15-utc-on-26-nov-2016

Not just quite as mild on the other side of the Cairngorm mountains on Speyside though.

thermograph-for-03063-aviemore-00-utc-on-23-nov-15-utc-on-26-nov-2016

The north south divide

Here is a plotted chart of the minimum overnight [18-06] temperature anomalies from this morning’s 0600 UTC SYNOP reports. An amazing contrast between the anticyclonic north and the windy south, with minimum anomalies ranging from as low as -11°C in the Highlands of Scotland, to +5°C along the coast of southeast England.

2016-11-24_132128

Recent global temperature anomalies

The relative warm temperatures across the pole are well illustrated in this anomaly chart for the week 4 November to 10 November 2016, as is the very cold Scandinavia and NE Russia. Unusually the temperatures across the central Atlantic are well above average despite the SST still being below average.

global-4-nov-10-nov-2016-anomalies

It’s no wonder that the Arctic sea ice is still tracking -19.5% below average for the 11th of November.

latest-arctic-sea-ice-11-nov

The Antarctic also shows some large positive anomalies in the interior and the Ross Sea for the first 10 days of November. Treat these contours with some caution because I’ve only just started to contour on a spherical projection and as you can see there are certain oddities on the edge of the globe!

1-nov-10-nov-2016-anomalies

 

Mild in the SW

air-temperature-c-1300-utc-on-sat-12-nov-2016

It’s very mild in the southwest of England at the moment behind the warm front/occlusion/occlusion.

air-temperature-c-1300-utc-on-saturday-12-november-2016-in-wmo-block-03-highest-air-temperature-c

The exceptional warm start to September

If you think that we’ve had in warm here in the UK during the first 14 days of September then it’s been very much warmer over central Europe with anomalies as high as +6°C. I  just wonder if the extreme warm anomalies that occurred over Russia during August, which were as high as +8°C for the entire month, have somehow retrogressed and migrated westwards.

air-temperature-anomaly-01-sep-to-14-sep-2016

The pressure patterns gives us the reason. The Icelandic low is misplaced, a little further southwest and 11 hPa deeper than usual, whilst a belt of high pressure stretched from the Azores to Poland with pressure anomalies of +4 in the southern Baltic Sea. This produced a conveyor belt of tropical maritime southwesterly for most of northwest Europe, but sunny, very warm or hot anticyclonic conditions for much of central Europe.

mean-sea-level-pressure-1-sep-14-sep-2016 mean-sea-level-pressure-anomalies-1-sep-14-sep-2016

 

 

13 September 2016 – Heat

The 13th of September 2016 apart from being our wedding anniversary, was quite an exceptional day temperature wise across a lot of  western Europe and eastern England. I always apply my own home grown rules when looking at maximum temperature anomalies.

  • -1 to +1 Near average
  • +1 to +4 Warm (or mild depending on the season)
  • +4 to +8 Very Warm (or exceptionally mild)
  • +8 – +12 Hot
  • >+12 Very Hot

The 13th was hot in a large area from the southeast way up to the northeast of England. There were some coastal exceptions but generally inland anomalies were above +10°C and in the top five SYNOP stations maximum anomalies exceeded +12°C.

maximum-temperature-anomaly-06-18-utc-on-tuesday-13-september-2016

Maximum temperature anomalies 06-18 UTC on Tuesday 13 September 2016

Here is the ranked list of hottest places. The highest 34.4°C occurred at Gravesend and made it the warmest September day since the infamous 35.6°C at Bawtry in 1906, there is some talk regarding its validity, but I’ll have a more detailed look at the observations from their in another article.  I remember Bawtry well because it was there I had my initial interview with the Met Office in June 1970.

maximum-temperature-c-0600-1800-utc-on-tuesday-13-september-2016-in-wmo-block-03-highest-maximum-temperature-c

Meanwhile in the more western parts thundery showers were tacking south north producing some severe thunderstorms and heavy rain, but more about that in another article – so much to do and so little time.

August Temperatures

Air Temperature Anomalies 01 Aug to 31 Aug 2016

Air Temperature Anomalies 01 Aug to 31 Aug 2016

I must admit that I never realised just how warm it had been over central Russia in August, a monthly anomaly of +8°C is something quite special. Other than that their were negative temperature anomalies over the Balkans (-2), Scandinavia (-1), North Africa (-1)  and of course the central Atlantic(-1).

Ten degree anomaly days – revisited

I wrote an article a couple of weeks ago about days that were either 10°C warmer or cooler than the long-term average and argued that these were days that could be truly be classified as very hot or very cold. I’ve just downloaded the recent reanalysis gridded (2.5° x 2.5°) surface temperature data for July, and thought that I would post a couple of screenshots from my application for the 19th of July 2016. They show the anomalies for 12 & 18 UTC derived from the 1948-2014 long-term grid point values and I think illustrate the point about classifying extremes.

1800 UTC Air Temperature Anomalies on Tue, 19 July 2016

1800 UTC Air Temperature Anomalies on Tue, 19 July 2016

June 2016: N hemisphere temperature anomalies

Air Temperature Anomalies 01 Jun to 30 Jun 2016

Surface Air Temperature Anomalies 1st – 30th June 2016

It’s the first time in a long time that surface temperature anomalies seem to be back to normal in the Barents sea region of the Arctic. The chart below is for temperatures and anomalies since the start of the year at 80N 40E, which is right in the middle of the Barents Sea between Svalbard and Franz Josef Land. The anomaly values of +20°C or more for much of the Winter look like something out of the film “The day after tomorrow” I know (but in reverse – sudden warming and not sudden cooling), but as far as I can see my application is doing its job and they are correct, and as I said temperatures there seem to have returned to normal since the end of April.

Mean Air Temperature & Anomalies for 1 January - 30 June 2016 [80.000 N 40.000 E]

Mean Air Temperature & Anomalies for 1 January – 30 June 2016 [80.000 N 40.000 E]

Elsewhere warm air dominated, particularly over central Russia (+8), the bulk of North America (+4) and large parts of Europe (+2), but the western North Atlantic ocean is still slightly on the cold side (-1). I’ve added labels for the various extremes to help you read the contours, which are more than a little convoluted this month. Below is a chart of air temperature anomalies since the start of the year have in the mid-Atlantic, at 50N 25W to be precise. As you can see it’s been predominantly cold throughout, with some short warmer weeks.

Mean Air Temperature & Anomalies for 1 January - 30 June 2016 [55.000 N 25.000 W]

Mean Air Temperature & Anomalies for 1 January – 30 June 2016 [55.0 N 25.0 W]

And because the gridded data is also six hourly, I can look back at spot values for any particular hour or day, here is the 1800 UTC on the 30th of June showing how quickly things can change in the very short-term.

1800 UTC Air Temperature Anomalies on Thu, 30 June 2016