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Autumn Forecast
I will start with the usual caveat that seasonal forecasts can and do go wrong. Predicting 5 days ahead is difficult enough – giving an exact forecast for a particular weekend in November right now is impossible. However I can give a guide as to what I am expecting.
My summer forecast was issued on June 3rd and is available for review if you scroll down quite a way - and I have posted on my old blog for easy access - http://jameswinfieldweather.blogspot.co.uk/2014/08/summer-forecast-2014.html.
My headline was for an above average summer in terms of temperatures, but also rainfall. Sunshine at least slightly above average. And the best chance of significant thunderstorms in our area for some years.
Amongst the things that I feel I got right were no month-long heatwave for July but good spells of hot weather - sunshine and temperature predictions for June and July, thunderstorm potential. August was furthest from being accurate, in particular by predicting average rainfall when we received well-above average though at least I stated that the month would be more unsettled in the second half which it has been. And I did have low confidence in my August forecast.
I am happy with the overall accuracy and will look to build in what I have learnt for next summer.
The headline for this autumn is for a dry September and October, often with above-average temperatures. A gradual breakdown to unsettled conditions in November with above average rainfall and an early taste of winter to finish.
September will begin with high pressure over the UK, or drifting to the east. This will bring lots of warm or possibly hot sunshine. There is the potential for it to briefly drift west bringing a cooler flow and perhaps some showers around 7th - 10th September. I then expect high pressure to move back over the UK to bring further warm sunshine for the rest of the month. Depending on the exact position of the high pressure, there could be some chilly nights in the second half of the month. Rainfall to be very low, perhaps as few as 3-4 days with rain falling, mostly from weak weather fronts toppling over areas of high pressure occasionally.
Overall I expect well-above average sunshine amounts, above-average temperatures and below-average rainfall.
I am 90% confident of this outcome.
October has a strong signal for high pressure to be to our east and this has been something that I have been confident about for several months now, which will mean southerly winds and well above-average temperatures at times, especially in the first half of the month.
The second half of the month is most likely to see the Atlantic high come into effect, bringing cooler north-westerly or northerly winds and occasional showers or weak weather fronts, but mostly dry.
Overall I expect above-average sunshine amounts, slightly-above or above average temperatures and below-average rainfall.
I am 70% confident of this outcome - less confident about the second half.
November will see the return of low pressure systems, though I expect the Jetstream to be tracking slightly north of here, say over Scotland so although rainfall will likely be regular, I expect that we will miss the heaviest of the rain. High pressure will likely nudge into the south at times so there will be a couple of 3-4 day drier spells.
I do feel that there is a chance of a brief cold spell towards the end of the month.
Overall I expect slightly below-average sunshine amounts, slightly above-average temperatures and above-average rainfall.
I am 80% confident of this outcome.
Early signs for winter are for a generally mild winter, and a wetter than average winter although there are no signals for it to be as extreme as last winter – in fact high pressure should nudge up from the south-west at times.
However, there are conflicting signals that it could be a very cold and very snow-filled winter, at least for January onwards. Certainly there is a much higher chance of snow this winter than last winter – which is something I stated before last winter. Added on volcanic uncertainty in Iceland and potential effects in the unlikely, but possible, event of a really major eruption and this winter is definitely one to watch.
Thankfully my winter forecast is still 3 months away!
If you have made it this far then it would be appreciated if you could share the forecast and/or invite friends. A lot of love and effort goes into this forecast and they are normally a reasonable indicator of the upcoming season.
Enjoy autumn
— in Reading.I will start with the usual caveat that seasonal forecasts can and do go wrong. Predicting 5 days ahead is difficult enough – giving an exact forecast for a particular weekend in November right now is impossible. However I can give a guide as to what I am expecting.
My summer forecast was issued on June 3rd and is available for review if you scroll down quite a way - and I have posted on my old blog for easy access - http://jameswinfieldweather.blogspot.co.uk/2014/08/summer-forecast-2014.html.
My headline was for an above average summer in terms of temperatures, but also rainfall. Sunshine at least slightly above average. And the best chance of significant thunderstorms in our area for some years.
Amongst the things that I feel I got right were no month-long heatwave for July but good spells of hot weather - sunshine and temperature predictions for June and July, thunderstorm potential. August was furthest from being accurate, in particular by predicting average rainfall when we received well-above average though at least I stated that the month would be more unsettled in the second half which it has been. And I did have low confidence in my August forecast.
I am happy with the overall accuracy and will look to build in what I have learnt for next summer.
The headline for this autumn is for a dry September and October, often with above-average temperatures. A gradual breakdown to unsettled conditions in November with above average rainfall and an early taste of winter to finish.
September will begin with high pressure over the UK, or drifting to the east. This will bring lots of warm or possibly hot sunshine. There is the potential for it to briefly drift west bringing a cooler flow and perhaps some showers around 7th - 10th September. I then expect high pressure to move back over the UK to bring further warm sunshine for the rest of the month. Depending on the exact position of the high pressure, there could be some chilly nights in the second half of the month. Rainfall to be very low, perhaps as few as 3-4 days with rain falling, mostly from weak weather fronts toppling over areas of high pressure occasionally.
Overall I expect well-above average sunshine amounts, above-average temperatures and below-average rainfall.
I am 90% confident of this outcome.
October has a strong signal for high pressure to be to our east and this has been something that I have been confident about for several months now, which will mean southerly winds and well above-average temperatures at times, especially in the first half of the month.
The second half of the month is most likely to see the Atlantic high come into effect, bringing cooler north-westerly or northerly winds and occasional showers or weak weather fronts, but mostly dry.
Overall I expect above-average sunshine amounts, slightly-above or above average temperatures and below-average rainfall.
I am 70% confident of this outcome - less confident about the second half.
November will see the return of low pressure systems, though I expect the Jetstream to be tracking slightly north of here, say over Scotland so although rainfall will likely be regular, I expect that we will miss the heaviest of the rain. High pressure will likely nudge into the south at times so there will be a couple of 3-4 day drier spells.
I do feel that there is a chance of a brief cold spell towards the end of the month.
Overall I expect slightly below-average sunshine amounts, slightly above-average temperatures and above-average rainfall.
I am 80% confident of this outcome.
Early signs for winter are for a generally mild winter, and a wetter than average winter although there are no signals for it to be as extreme as last winter – in fact high pressure should nudge up from the south-west at times.
However, there are conflicting signals that it could be a very cold and very snow-filled winter, at least for January onwards. Certainly there is a much higher chance of snow this winter than last winter – which is something I stated before last winter. Added on volcanic uncertainty in Iceland and potential effects in the unlikely, but possible, event of a really major eruption and this winter is definitely one to watch.
Thankfully my winter forecast is still 3 months away!
If you have made it this far then it would be appreciated if you could share the forecast and/or invite friends. A lot of love and effort goes into this forecast and they are normally a reasonable indicator of the upcoming season.
Enjoy autumn
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