A tornado alert has been issued for the South West. From Cornwall to Gloucestershire, the yellow severe weather warning covers most of the region as well as the south east and Norfolk.
The weather warning was issued by severe weather watchers TORRO, the Tornado and Storm Research Organisation. Its warning says severe thunderstorms could hit part of the southern part of England. TORRO, founded in 1974, keeps records of tornadoes, large hail and severe storms across Britain and Ireland, as well as issuing forecasts when there is a risk of severe storms.
On its website, TORRO defines a severe thunderstorm as producing one or more tornadoes and / or waterspouts, hail with diameter of at least 20mm as well as non-tornadic winds gusting to 55mph.
TORRO’s tornado alert map shows north and south east Cornwall affected by the yellow warning for severe weather along with Devon, Somerset, Bristol and Gloucestershire as well as Dorset and Wiltshire.
On the forecast for the rest of today and into tomorrow, TORRO said: “A shortwave trough will move east north east this afternoon/evening, accompanied by areas of showery rain, some convective in nature.
“One or more small-scale circulations may evolve, although model guidance differs somewhat on the exact morphology. Gusty winds, hail (perhaps up to 1cm diameter), and occasional cloud to ground lightning may accompany the stronger cores.”
They added: “Additionally, isolated tornadoes are possible, especially if any mesolows form. Any such mesolows would produce a more focussed risk corridor for gusty winds and occasional tornadoes.”
Mesolows are highly localised area of low pressure. According to TORRO, the UK experiences about 36 tornados every year.