Met Office says Spanish plume thunderstorms likely next week
The Met Office has warned that a classic Spanish plume will sweep across the UK, bringing temperatures of 28 °C and severe thunderstorms.
The Met Office has upgraded its outlook for the coming days, warning that a classic “Spanish plume” could sweep across the UK from Monday 31 August. Temperatures are set to climb to 28 °C on Wednesday 2 September, a change that will create the instability needed for the country’s “most explosive weather phenomenon” – widespread thunderstorms with lightning, hail and heavy rain. For commuters, outdoor events and insurers, the shift from a warm, dry spell to potentially hazardous convective weather matters now because the storms are expected to persist for several days, with the most intense bouts forecast for Wednesday and Thursday.
What a Spanish plume looks like
The Met Office describes a Spanish plume as a situation in which warm air travelling north from the Iberian Peninsula meets cooler air moving in from the Atlantic. As the hot air rises into the cooler layer, the atmosphere becomes highly unstable, encouraging the rapid development of thunderclouds. The agency’s own wording calls it “the UK’s most explosive weather phenomenon”. BBC Weather forecasters add that the warm surge will allow “low pressure and frontal systems to approach from the southwest”, further boosting the chance of “thundery outbreaks”.
Media additions
When the plume materialises, the typical mix includes lightning, thunder, hail, downpours that can exceed 45 mm in an hour, and gusty winds that can damage trees and structures. The combination of heat and moisture also means that rain showers can become “widespread and heavy”, according to the Met Office forecast.
Day‑by‑day outlook
| Day | Date | Expected conditions |
|---|---|---|
| Monday | 31 August | Sharp showers likely in the south‑west, early signs of instability. |
| Tuesday | 1 September | Showers and thunderstorms spread northwards; temperatures rise slightly. |
| Wednesday | 2 September | Peak temperature around 28 °C; heavy, scattered thunderstorms; chance of intense downpours. |
| Thursday | 3 September | Continued widespread heavy rain; thunderstorms persist across England and Wales. |
| Friday | 4 September | Unsettled weather remains, though rain intensity eases; temperatures near or above average. |
| Weekend | 5‑6 September | Persistently changeable, with lingering showers and occasional thunder. |
The Met Office notes that the showers will become “increasingly widespread and heavy on Wednesday and Thursday”, while BBC Weather adds that Wednesday may start drier with sunshine before “further scattered hefty showers and thunderstorms” develop later in the day.
Historical perspective
A similar pattern in July 2014 produced more than 62 000 lightning strikes in just five days, with some locations receiving 45 mm of rain in a single hour. That event highlighted how quickly a Spanish plume can transition from isolated showers to an intense, damaging storm system. The current outlook mirrors those past conditions, prompting the Met Office to stress the need for vigilance, especially in regions prone to flash flooding.
Why the forecast matters now
Beyond the immediate risk of lightning and flooding, the temperature spike to 28 °C may temporarily push daily averages into the “near or above average” range for late August, nudging the UK closer to the thresholds that trigger heat‑related health advisories. The combination of heat and storms also raises the likelihood of power outages, as gusty winds can down lines while heavy rain overloads drainage systems.
Emergency services are already monitoring the situation. Local councils across England and Wales have issued reminders to keep sandbags handy and to avoid non‑essential travel during peak thunderstorm periods. For outdoor festivals and sporting events, organisers are being urged to have contingency plans for sudden rain and lightning threats.
What to watch next
- Temperatures: Watch for the 28 °C peak on Wednesday, the highest temperature for the week.
- Lightning risk: Expect a surge in strikes, especially in the south‑west on Monday and expanding northwards by Tuesday.
- Rainfall intensity: Heavy downpours could exceed 45 mm in an hour, raising flash‑flood concerns.
- Wind gusts: Gusty winds may accompany thunderstorms, increasing the chance of structural damage.
- Weekend outlook: While rain intensity should ease, unsettled conditions will likely persist into Saturday 5 September.
Residents are advised to keep an eye on the Weather coverage page for live updates, and to heed any local warnings issued by councils or emergency services.
Sources
Details of the forecast and the science behind the Spanish plume come from the Met Office, as reported by Mirror and the Stoke Sentinel. BBC Weather’s interpretation of the model outcomes is woven throughout the day‑by‑day expectations.
