One Very Acurate Forecast

[chapmanraven]

This was published in the Harborough Mail in October 2008, its spot on for the snow we have just had. Thought some of you may find it interesting I have added the link to the Harborough Mail web site.

Weather tips from Joyce

Published Date: 16 October 2008

LOCAL amateur weather forecaster Joyce Dunkley of Little Bowden, has produced her forecast for the autumn/winter, based on observations taken at the autumn equinox.

She has warned of a cold winter, with the worst of the weather in the New Year, when there could be spells of heavy snow.

December will bring a cold, but mainly dry, few weeks but it should be milder around Christmas.

Miss Dunkley correctly forecast a misty start to October, dry and a few sunny days, but we should be prepared for high winds in the last two weeks.

November will be an unusually bright month, cold but dry with a few misty days and an odd frost.

There will be a cold and windy start to January with a little sun and frosts, turning even colder with a strong chance of snow after the 20th.

February will be the worst month of the winter, cold and windy with heavy snow for the first two weeks. March will be changeable with the possibility of snow showers.

The full article contains 176 words and appears in Harborough Mail newspaper.

Page 1 of 1

* Last Updated: 14 October 2008 12:35 PM

* Source: Harborough Mail

* Location: Market Harborough

Here's the link to the web page.

oops missed off the link to Harborough Mail

http://www.harboroughmail.co.uk/news/Weath...oyce.4591503.jp

[Tom D]

It's a very brief description, anyone can say that it'll be cold and windy in February. She may have forecast a misty start to October but she evidently didn't predict the snow the south got in late October.

And that forecast for March is even more vague!

My forecast for June 2009 is some sunshine but the possibility of some rain

[johnholmes]

why is it some people always want to knock?

[Timmead]

In fairness Feb was the only partially correct forecast. November cold and sunny! October windy! Snow for late Jan! Mild Christmas! You get the message. Probabilistically, 'Joyce' was likely to get something right. Thus the fact that she got everything else wrong (especially nearer the forecast time!) provides strong evidence for a very poor forecast. So indeed, interesting that some will get sucked into thinking the forecast was any better than the one I could have picked out of a hat.

[Guest]

The weather does follow a loose pattern every year, pretty well, somtimes there are exceptions but this is what we get on average according to MetCheck:

From To Usual Weather Confidence Weather

8 Feb 16 Feb This period usually sees the years highest frequency of high pressure across the UK and is usually the coldest period of the year. A good period to head off to the Alps for some ski-ing 56%

21 Feb 25 Feb A 'Northerly Blast' is quite common during this period as low pressure crosses the UK and snowfall affects many areas. 42%

26 Feb 9 Mar A stormy and cool period usually dominates this period bringing occasional Northerly outbreaks followed by wet and windy weather as storms move in from the Atlantic and settle over Norway. 88%

10 Mar 22 Mar A settled period as the first of the Spring anticyclonesaffects the UK. As daylight hours are longer this period can sometimes see very mild weather during the day but hard frosts at night. 55%

23 Mar 31 Mar March usually ends on a stormy note and starts the first of the 4 Northerly Spells which last through April and into early May bringing the traditional showers. 67%

10 Apr 19 Apr This is probably the most relaible of the Northerly showery outbreaks for the entire year. Low pressure to the East brings cold showers to many areas with snow possible in Scotland. 71%

23 Apr 16 May Again, a cool period usually, however the Atlantic starts to quieten down and winds from the North or East are very common whilst Westerlies are rare. 67%

17 May 31 May This period is known as the fore-monsoon, traditionally dry and warm with high pressure over the UK and continent. 88%

1 Jun 4 Jun The first wave of the 'European Summer Monsoon' as low pressure moves in from the West bringing cooler weather and heavy slow moving showers. 77%

10 Jun 14 Jun The second wave of the 'European Summer Monsoon' bringing more wet and windy weather, between the periods expect better weather as the Azores high begins to expand. 77%

18 Jun 27 Jun The third and final wave of the 'European Summer Monsoon' brings more wet and windy weather to the UK with further heavy showers. 77%

10 Jul 22 Jul A traditional warm period for the UK, the first of the 'Phew, whatta scorcher!' headlines hits the press as the Azores high builds and extends over the UK. 50%

23 Jul 27 Jul Spanish plumes and stagnant areas of low pressure are very common during this period bringing heavy thunderstorms. 77%

31 Jul 8 Aug Again, a potentially thundery period of the year but this is the period where the hottest day of the year is likely to occur. 50%

16 Aug 30 Aug Summer starts to fade as the first of the Autumn storms arrives bringing cooler, unsettled weather to many areas, high pressure may hang on in the South for a while longer. 67%

1 Sep 17 Sep The 'Old Wives Summer' begins as high pressure crosses the UK en route to Siberia bringing a period of 3 or 4 fine days followed by showers. 87%

18 Sep 24 Sep The Atlantic starts to return more Autumn storms during this period, the period around 23rd/24th is liable to gales. 60%

5 Oct 12 Oct Again, a wet and windy period of the year bringing more Autumn gales to the UK. 67%

16 Oct 20 Oct A traditionally settled period as high pressure builds and crosses the UK. 67%

24 Oct 13 Nov This period is known as the 'Autumn Rains or Continental Trains' as the period starts wet and windy with gales from 26th-29th however high pressure sometimes builds from the East on the 30th. 100%

14 Nov 24 Nov A traditionally settled period as high pressure settles over the UK bringing quiet, foggy weather to the UK. 65%

25 Nov 10 Dec A wet and windy period of the year usually as cyclonic systems move in from the Atlantic, the two most stormy periods are 25th - 29th November and 6th - 12th December. 98%

18 Dec 24 Dec The pre-Christmas period brings the winter solstice and also a traditionally quiet and frosty period of the year as high pressure dominates the weather. Gales still possible in Northern areas. 56%

25 Dec 31 Dec One of the most traditional periods of the year where in many years the Atlantic brings gales and heavy rain/sleet or snow back to the UK during the festive week. 83%

5 Jan 17 Jan A traditionally wet and windy period of the year as the Atlantic begins to become more active, however storm systems affect mainly western areas. 87%

18 Jan 24 Jan Dry and frosty as high pressure begins to affect the UK, Easterly winds are quite common during this time. 87%

24 Jan 3 Feb This period is notorious for gales and severe gales to affect the UK with snowfall a high risk to many areas. 85%

So I wonder if this lady has anything specific to forecast for the summer?

[Roger J Smith]

One thing this thread demonstrates too, is that we need to have a numerical basis for any LRF, otherwise it becomes a case of subjective interpretation that can have defenders saying "this was pretty close" and detractors saying "no it was way off" with no real way to decide the issue. The main elements of a seasonal forecast would be the three monthly temperature anomalies, the overall seasonal anomaly, and the three monthly precip anomalies and seasonal anomaly. If you could also get specific statements about sunshine hours and any verifiable statements about storm dates, severity etc, then you have something to compare with reality. If you just say, I think this will be a mild spring, almost anyone might be impressed or put off by it just on a whim.

As to the interesting list of what climatologists call "singularities" (recurrent themes in annual weather) I think many have looked into this and found some based on departures from random distribution.

One well known singularity is the so-called Ice Saints days of May 11 to 13. I forget all the details of the term "ice saints" but the fact was noted in the Middle Ages that around May 11 to 13, there was a tendency for a frosty return to late winter conditions in Europe, so I suppose the daily saints were thought of as the ice saints. Now we need to realize that the calendar was shifted in Europe in 1582 so it would depend on whether that belief arose before or after 1582, whether to apply this to May 11 to 13 nowadays, or otherwise, to May 21 to 23.

From what I've seen of British weather, I think these singularities apply:

late November to early March -- much snow in Fantasy Island

mid-March to late May -- summer

June to August -- can be tolerable, as long as RJ Smith not on holiday in the UK, if so, cold with rain

September to mid November -- succession of deep lows at T+144 bringing fear to many, eventually drizzling on Iceland.

[Nick H]

The weather does follow a loose pattern every year, pretty well, somtimes there are exceptions but this is what we get on average according to MetCheck:

...

17 May 31 May This period is known as the fore-monsoon, traditionally dry and warm with high pressure over the UK and continent. 88%

The last week in May actually shows a cooling, for the south east at least, and is often wet and windy.

As for Ms Dunkley's forecast, I wouldn't say it was that accurate. The start of January wasn't especially windy, there was more than "a little sun", it didn't turn even colder, and there wasn't snow after the 20th.

November was also inaccurate: it might have been dry (but not exceptionally so), it certainly wasn't abnormally cold and it was rather dull.

Edited February 11, 2009 by Nick H

[chapmanraven]

She said heavey snow first to weeks in Feb and thats what we got. For me thats pretty acurate considering it was forecast last october. Yes I agreed the rest is pretty sketchy, but she usually gets major events right. Don't forget she only has a few lines, a couple of times a year in the local news paper. She may well be able to give a more detailed forecast, with only a sideline in a local paper to go on, that is only supposition.

Anyway as I originally said I thought it was interesting, I didn't say it was gospel.