Reigate is in an interesting location regarding the much anticipated snow tomorrow! Whilst we will not experience anything like the metres of snow winter storm Nemo has delivered to Boston today, by Sunday evening Reigate is forecast to be on the edge of some exciting snowy weather to the north and east and in a superb position to watch events unfold as we sit on the battle front between warm (rain) and cold (snow) air! It is due to rain most of the day on Sunday and turn to snow in the evening, initially and most significantly, over the North Downs. Small gains in altitude could make a difference in whether you see snow or sleet or rain tomorrow: it’s that close!
The LOW bringing all the uncertainty in the forecast is due to slip SE during tomorrow. It has warm air wedged between fronts to the south and west where precipitation will certainly fall as rain, some of it heavy. On the leading edge of the advancing warm front, winds will turn increasingly Easterly during Sunday and drag in progressively colder air, especially over night into Monday morning. This drop in temperature on Sunday afternoon is what will change any rain into snow /sleet. By Sunday evening the warm front is due to be near Reigate but forecasts suggest it will stall and then slip south enhancing those cold easterlies but, at the same time, moving away the heaviest precipitation overnight which will peter out early Monday morning. Temperatures will be above freezing throughout the day but only around 2 or 3°C, cold enough for evaporative cooling to create some local snowfall in heavy rain (see post yesterday). Winds increasing to 30mph gusts in the afternoon will make it all feel thoroughly unpleasant. Whilst rain and sleet are MOST likely all day, the zero-degree / freezing altitude decreases dramatically further north and east from Reigate. Snow is therefore possible on the North Downs as even small increases in altitude locally could potentially add significant accumulations if we are positioned on the leading edge of the front for a period of time. There is also a risk of snow settling lower down during Sunday afternoon and evening but temperatures are such that sleet seems most likely. Total rainfall for the day is forecast to be up to 10mm so it will be a wet day regardless of how much snow falls. Any snow falling in the evening could accumulate 2 or 3cm of snow, especially on the Downs. So, to summarise, Reigate tomorrow is due to be increasingly wet and breezy as the day progresses, temperatures 3ºC, falling to 1ºC overnight to Monday. Heaviest rain will be in the late afternoon / evening (6pm onwards) and this might turn sleety / snowy, especially over the Downs. The forecast is full of uncertainty but, whatever turns out, do enjoy being in a pivotal meteological location tomorrow! Meanwhile, scattered wintry showers are developing over our region this evening (Saturday).