With temperature anomaly -2,9°C from long-term average is the first May week in Central England /https://www.metoffice.gov.uk/hadobs/hadcet/cet_info_mean.html/ the coldest in all-time history, since records began (1659).
During the first May week gradually appeared in the UK snowing /https://mkweather.com/scotland-and-northern-england-under-the-snow-in-may-exceptionally-cold-spring-2021-continues// or severe frosts /https://mkweather.com/third-may-night-in-the-uk-with-6c-all-time-may-temperature-record-for-northern-ireland-should-be-broken// up to -6°C during the nights.
Extremely cold weather, with snowing and monthly temperature records for May is reported from large parts of northern and western Europe /https://mkweather.com/finland-hit-severe-snowstorm-with-30cm-of-fresh-snow-oulu-only-3-days-above-10c-since-winter-year-without-spring/; https://mkweather.com/snowing-in-the-netherlands-on-7-may-extremely-rare-snowstorm/; https://mkweather.com/snowing-in-potsdam-berlin-germany-in-may-after-50-years/; https://mkweather.com/scotland-and-northern-england-under-the-snow-in-may-exceptionally-cold-spring-2021-continues// and /https://mkweather.com/frosts-ground-frosts-and-monthly-records-in-the-spain-northwestern-spain-30c-andalusia-46c/; https://mkweather.com/france-extreme-frosts-are-back-monthly-may-temperature-records-overcame/; https://mkweather.com/germany-monthly-records-for-may//..
According to ESRL composites for early May 2021, we should notice large cold anomaly in 850 hPa below -5°C from Ireland, the UK northern France, Benelux to Germany, Denmark, Czechia, Poland, Baltic states, eastern Sweden, Finland and northern European Russia, with maximum above Benelux and southern Finland, up to -8°C.
Negative anomalies in H850 (geopotential at 850 hPa level) are very strong from the UK to Sankt Petersburg region.
Negative temperature anomalies in 2 meters are evident from NE Portugal to Ural region, Russia, the strongest in NW Spain, Pyrenees, eastern France, Central England, Benelux, Germany, western Alps, southern Scandinavia, Poland, Czechia, Baltic states and northern half of European Russia.
Composites of Meridional and Zonal Wind parameters are showing negative anomalies in region between Iceland, British Islands and Scandinavia, while mid-latitudes were more windy.
Average temperatures from the first week of May 2021 are in Central England lower than average temperatures in March 2021 and only +1,9°C higher than in February 2021.
Long-term outlooks for northwestern Europe are cold /https://mkweather.com/may-2021-in-europe-long-rounds-with-severe-storms-and-2-heatwaves-in-outlook/; https://mkweather.com/245c-in-iceland-signalizes-extremely-cold-conditions-until-early-summer-2021-in-n-w-europe-year-without-spring/; https://mkweather.com/summer-2021-forecast-for-europe-hot-and-dry-pattern-as-leading-heatwaves-drought//.
According to ECMWF outputs, cold weather should in British Islands, parts of Scandinavia and NW coasts of Europe persists until the mid-June 2021.
Snowing in elevations below 1000 MASL in Scotland in June won´t be surprise this year, thanks to La nina /https://mkweather.com/global-temperatures-dramatically-went-down-the-sharpest-jump-since-1990s-la-nina//.
Source of composites: Daily Climate Composites: NOAA Physical Sciences Laboratory
Source: https://www.metoffice.gov.uk/hadobs/hadcet/cet_info_mean.html