Insight
Why is it not beginning to look like Christmas in Northern Ireland?
It is the last month of meteorological autumn but there is just no sign of any cold weather and there is the potential to break November weather records.
Over the next few days temperatures are expected to be similar to the temperatures we would experience in May, somewhere between 15°C to 17°C. So it is likely that the current warmest Armistice Day 15.9°C on 11 November in 2015 will be broken.
Overnight temperatures are also anomalously high. The highest minimum temperature ever recorded was 13.9°C on 21 November 1947. This means that if 14°C is recorded overnight, this will become a new minimum temperature record.
Whether records are broken or not, I am sure that you would agree it really doesn’t feel like November.
Why is it so mild?
The jet stream the boundary between cold air from the Arctic and warm air from the equator. If we are to the south of the jet stream, this implies we are in milder or warm air, usually associated with a higher humidity.
Since October, the jet stream has on a few occasions become stuck in a ‘trough’ position. This means the jet stream is not moving from west to east, but moving from south to north, allowing warm and humid air from much further afield to reach Northern Ireland.
In this case the air is coming from the Azores in the middle of the Atlantic. As long as the jet stream remains in this position, there will be a constant supply of unseasonably mild weather.
Is there any cold weather on the way?
The forecast for the rest of November is for a mobile weather pattern. This means the the jet stream will continue to drive weather systems across the Atlantic in our direction with a likelihood that the main wind direction will be westerly or south-westerly meaning we will continue to experience a very mild November.
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