Friday 17th April
The showery activity was minimal on Thursday, what was observed on the radar was towards the northwest later in the afternoon, which resulted in a dry, warm and sunny day over Marlborough. As a result the thermometer edged upwards to reach a maximum of 16.4C at 13.34, before more clouds arrived that reduced the sunny periods. However, the high was a welcome 2.1C above average as was the minimum of 9.4C logged at midnight, which was a significant 5.5C above average. In fact the temperature eased upwards in the early hours of Friday resulting in a temperature of 11.1C at 08.00.
Friday arrived without any sunshine, so a dull but relatively bright start that will fade as the morning progresses. The culprit is a cold weather front heading our way with associated cloud ahead of the front, which will cross our region later today producing rain for a period. The radar at 08.00 indicated that the first rain had crossed Cornwall and west Devon and likely to arrive over Marlborough late afternoon.
The high pressure to the southwest will continue to build across the UK on Saturday squashing out any weather fronts. However, later on Saturday, as the centre of the high pressure moves northwards across the country, the wind will back into the north then further into the northeast on Sunday, a cooler direction.
The new position of the high, between the UK and Iceland, will bring the cooler air stream that will result in maxima dropping to near average for April of perhaps just below, also much cooler nights. Sunday and Monday before dawn will see the temperature dip to low single figures. Perhaps gardeners should be ready to protect any tender plants out in the open, also to shield from a modest cold northeasterly breeze that will last well into next week.
The forecast for next week seems to be a generally drier and brighter few days with variable sunshine.
Part two of the Met Office press release of the effect of a possible stronger than normal El Niño event
Crossing important thresholds
Sea surface temperatures across a key region of the central Pacific have been rising steadily in recent months. Observations show that temperatures have crossed important thresholds that are used internationally to identify El Niño conditions.
Satellite measurements also reveal that sea levels in this part of the Pacific are increasing.
Warmer water expands, so rising sea level is another strong indicator that additional heat is building in the ocean. The pace and scale of these changes suggest a well-established warming signal rather than a short-lived fluctuation.
Forecasts based on multiple climate models point towards continued warming through the summer and to the end of the year. What stands out is how closely these forecasts agree with one another. When model projections cluster tightly together, it increases confidence that the overall direction of change is robust.
Grahame Madge, Senior press officer and climate science communicator at the Met Office said: “Other organisations around the world have other definitions and thresholds for what constitutes El Niño conditions, but this will be such a significant event, if it happens, that it will be above all of those thresholds and there will be no doubt that we’re in an El Niño.”
How strong could this event become?
Current projections suggest this El Niño could become a strong event, potentially comparable with some of the most impactful episodes in recent decades. El Niño events often peak towards the end of the year, with maximum influence typically felt between November and February.
There has been discussion in the media about a “super” El Niño. While that term is not officially recognised by the Met Office, there is growing confidence that this event could sit at the upper end of the historical range.
Grahame explained: “A ‘super’ El Niño is not a term we subscribe to, but it does underpin the fact that this is likely to be a significant event. Scientists are telling us that this could be the strongest El Niño event this so far century, comparable to the notable El Niño event in 1998.”
Regional impacts around the world
El Niño reshapes rainfall and temperature patterns across the globe, though impacts vary by region and by season.
Areas close to the Pacific, such as parts of South America, can experience much wetter conditions, while regions including eastern Australia, Indonesia and parts of South-East Asia often become drier and warmer than average. Reduced rainfall in these areas can increase drought risk and raise the likelihood of wildfires.
In parts of Africa, El Niño can shift rainfall patterns, bringing drier conditions to some regions and wetter conditions to others. India can also experience disruptions to the monsoon, which has significant implications for agriculture and water resources.
In North America, El Niño years are often associated with wetter conditions across parts of the southern United States, including California, while also influencing storm tracks further north.
For the UK, the effects of an El Niño event tend to be less discernible. Whilst higher temperatures can be more likely during summer, the impact on the UK’s weather may be stronger during the later winter months being wet and mild.