Quick update Tuesday: This LOW is not now predicted to trouble UK Fri – Sat: it will not be the BLOCKBUSTER we hoped might break through and bring milder conditions. Instead, it’s a near miss to the South as the LOW skirts thru NFrance pushed aside by the Icelandic HIGH building once again to the North of UK. LOW to south WILL drag in more cold / cool easterlies through much of next week; so start of April will be cool but should be not quite so cold as now with daytime Tmax +6-7°C for Reigate. Nights still frosty. Mostly dry, poss of snow showers. No dramatic snow on the charts for Reigate at the moment. Point to note: Hekla volcano in S Iceland is seismically active: heightened eruption possibility. Hekla is not usually a show-stopper for air traffic and winds would blow ash away from Europe!
How and when will this record breaking cold weather end? Models suggest the first week of April will still be cool but not quite as cold as now. The latest UKMO chart for the end of the week shows mild SW winds developing around a huge Atlantic depression and squeezing up against the cold air towards Southern England. The leading edge of fronts pushing up the Channel into southern England could bring snow for a time to the south, and possibly lots of it, as cold air undercuts the warm and forces it up. The snag will be if these fronts stall for a while: the chart shows fronts parallel to isobars which usually means they are slow moving and could stick around, thus increasing any precipitation over areas underneath. Later models also show this LOW slipping to the south of the UK which will drag in more cool Easterlies for the start of April. Too early for details, could change… but this LOW may not be the blockbuster we all hope for to sweep away the cold!