SSEN's Weather Watch for July 2017
A quick look back at June, courtesy of the Met Office, reveals it was a warm and wet month; England experienced its equal second warmest June on record (since 1910) and Scotland had its equal-wettest June (shared with 1938).
Our forecast for July sees the month having three different types of weather pattern. We expect the weather to become hotter during the first week as a pulse of hot air drifts north from France to cover England and Wales. It won’t last too long and probably will fail to reach Scotland and Northern Ireland. Temperatures are likely to peak at 27-30C in the London area on Thursday 6 and Friday 7 July. The hot and humid air will bring a high risk of thunderstorms to parts of England on Thursday 6 July – a combination of thunderstorms moving across from the English Channel and others growing rapidly overhead in response to the unstable air. Southern, central and eastern England will be in the firing line and, although not a widespread event, localised impacts could include intense downpours and flash flooding.
A change of wind direction will then bring one to two weeks of weather coming in from the nearby Atlantic Ocean – a westerly flow will certainly limit the risk of heatwaves and thunderstorms, and instead fresher air will cover the UK and Ireland for quite some time.
The map on the main page image shows the average positions of the high and low pressure systems for the five days starting 14 July. Low pressure will be dominant near Iceland as the high pressure remains near the Azores. In mid July, this weather pattern would bring widespread below average temperatures to Europe, with the exception of Spain, Italy and Greece. Some wet and windy interludes are likely, notably across Scotland – with most rain falling near the west coast, as active weather fronts head east. Sunshine levels are expected to be below average for the time of year.
The weather for the last week of the month should become settled with more frequent spells of high pressure – hopefully this will ensure some very pleasant summer weather as temperatures and sunshine levels return to average or above average.
Finally, an above average Atlantic hurricane season is most likely this year (June to November), as predicted by NOAA (in the graphic above), mostly due to above average sea surface temperatures across the tropical Atlantic Ocean and the Caribbean Sea, as well as favourable wind conditions for tropical storm development.
For more weather information you can follow our senior meteorologist, Simon Cardy on twitter @weather_king