Met office advisor update - warnings issued

Here is an update to the weather we expect to see in the next few days as we see a change from the current, hot conditions to something cooler and more unsettled.

Headline:

Heavy showers and thunderstorms are expected to develop over the next few days which could lead to difficult driving conditions, disruption to transport, power outages and surface water flooding.

Warnings Issued:

• Yellow THUNDERSTORM Warning (Very Low Likelihood of Medium Impacts) valid 1600 on Thursday 25th June to 0900 on Friday 26th June 2020 (Hampshire, Sussex, Surrey, southern Thames Valley and small part of SW Kent).
• Yellow THUNDERSTORM Warning (Very Low Likelihood of Medium Impacts) valid 1200 on Friday 26th June to 0600 on Saturday 27th June 2020 (Surrey, central and northern parts of the Thames Valley and just touching into northeast Surrey and East Sussex) .

Today / tomorrow:

Fine, dry, sunny and very warm today and tomorrow with temperatures rising to the high-20s to low-30s Celsius. Coastal areas will see slightly lower temperatures as sea breezes develop but it will still be very warm. Tomorrow will see slightly lower temperatures in eastern areas too as a slightly stronger, easterly wind develops.

In line with the PHE/NHS Heatwave Plan, the Met Office have issued a Level-2 Heat-Health watch for SE England indicating a 70% risk of meeting trigger temperatures. It currently looks like temperatures will not widely reach the trigger (i.e. 2 days of 31 Celsius with a night of 16 in between) but it will be close and it is possible a few locations could just meet the criteria.

Thursday night / Friday:

After a generally dry evening, heavy showers and thunderstorms are expected to move from the southwest overnight, possibly bringing some torrential downpours in places. These showers could give 30-40 mm of rain in less than 2 hours and will be accompanied by lightning and hail. Theses showers will gradually move northeast overnight but south-western areas of SE England will be at the greatest risk overnight and at first on Friday morning.

The overnight showers and thunderstorms are currently expected to ease for a time on Friday morning before reinvigorating again as temperatures rise. By this time the risk transfers further northeast with the risk much lower across Hampshire and West Sussex. These showers could give 30-50 mm of rain in an hour, accompanied by hail and lightning. The showers are expected to clear to the northeast late afternoon and evening. The temperature will remain in the high-20s or low-30s on Friday.

The Met Office have issued a Yellow THUNDERSTORM Warnings (Very Low Likelihood of Medium Impacts) to cover the potential impacts from the heavy showers and thunderstorms on Thursday night (southern and western areas) and during the day on Friday (northern and eastern areas). Impacts could include difficult driving conditions, disruption to transport, power outages and property damage due to lightning strikes, and flooding of isolated homes and businesses from surface water flooding. The Flood Guidance Statement is Yellow to cover the same risk areas.

Saturday / Sunday:

Generally rather unsettled on Saturday with showers or longer spells of rain, isolated heavy with thunderstorms. Remaining unsettled on Sunday but with only light showers or rain in places. Temperatures rising into the low-20s Celsius.

Please keep up to date with the latest Met Office forecast details on Met Office website.