The Met Office has issued a thunderstorm warning for a large part of Wales as the period of settled weather comes to an abrupt end. The forecasting agency warns of “frequent lightning, gusty winds, potentially some large hail, as well as brief spells of heavy rain”. A yellow warning is in place on Friday from noon until 8pm.
According to the Met Office, “A few thundery showers may be present across southern and southeast England early on Friday, but from the middle of the day, they are expected to develop more widely within the warning area.” The warning adds: “Whilst some places will remain dry, where thundery showers do occur, they will bring frequent lightning, gusty winds, potentially some large hail.” As much as 15 to 25 mm of rain could fall within an hour, with a very small chance of 30-40 mm falling in three hours. Showers are expected to ease and fade during Friday evening.
The areas covered by the weather warning are: Blaenau Gwent; Bridgend; Caerphilly; Cardiff; Carmarthenshire; Ceredigion; Merthyr Tydfil; Monmouthshire; Neath Port Talbot; Newport; Pembrokeshire; Powys; Rhondda Cynon Taf; Swansea; Torfaen; Vale of Glamorgan.
Before that, Thursday will be warm and sunny after a cloudy and murky start to the day. The forecast for Wales says: “Cloudy and perhaps misty for many at first, though the cloud will soon lift and break to leave warm sunny spells into the afternoon. Breezy, especially around hills, at times. Maximum temperature 21 °C.”
Friday will see another cloudy start with sunny spells breaking through, but there will be a risk of scattered showers later, these possibly turning heavy and thundery. The Met Office outlook for Wales for Saturday to Monday says: “Mostly unsettled over the weekend and next week with heavy, possibly thundery showers and longer spells of rain at times, mixed with sunnier intervals. Feeling warm and humid.”