By Eric Leister, AccuWeather meteorologist
June 20,2017, 8:20:12AM,EDT
The hottest air of the year settled across parts of the United Kingdom early this week, and some areas will not get relief until late in the week.
Temperatures reached 32 C (90 F) in London on Monday, the earliest occurrence of such heat since 2005 when the mercury reached 32.8 C (91 F) on 19 June.
While the heat peaked for some locations on Monday, dangerous heat will remain across southern England into Wednesday with daily high temperatures between 27 and 33 C (80 and 91 F).
Wednesday could set the bar as the hottest day of the year so far in the U.K.
Along with the heat, high levels of humidity will make it feel even hotter creating dangerous conditions for the elderly and children and increasing the risk for dehydration, heat exhaustion and heat stroke.
Anyone attending the first day of Glastonbury on Wednesday can expect hot and humid conditions with a mixture of clouds and sunshine. The high is expected to be near 30 C (86 F).
Cooler and less humid air will arrive on Thursday with further cooling expected from Friday into the weekend.
Along with the change to lower temperatures, there will be a threat for some rainfall on Saturday and Sunday.
Attendees of Royal Ascot 2017 can expect to deal with hot and humid weather through Thursday before a shift to cooler weather on Friday and Saturday. A shower could briefly dampen festivities on Saturday.
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While southern parts of the U.K. will have to wait until at least Thursday for cooler air to arrive, some relief was felt across northern Wales and northern England on Tuesday.
Another round of heat and humidity is expected on Wednesday with highs near 27 C (80 F) in the warmest locations of northern Wales and northern England.
This surge of heat and humidity will be accompanied by the threat for severe thunderstorms Wednesday afternoon from the Midlands into Northern England.
Temperatures will then fall several degrees each day from Thursday through Saturday as more seasonable air settles over the region.