I’ll fully admit before I start that a inter-comparison between the ECMWF based forecast presentation from MeteoGroup and that of the Met Office’s with their own model data on a day of reasonably benign weather like today is a little bit over the top.
The ECMWF model does have a finger of showers running down the east coast but Simon King doesn’t (or forgets) to mention them in this particular broadcast at 12 am, even though he’s under no obvious time pressure (fig 1). The MeteoGroup graphics showed little or no low cloud across the southeast of England, which prompted him to say “a bit of cloud feeding into central areas, but either side of that we’ll continue with the sunshine into the afternoon” (fig 2). So nothings changed with the presenters, they believe the NWP in the graphics rather than check the latest observations, weather radar and visible satellite image. It’s as much the presenters fault as it is MeteoGroup and they now all work for the BBC and not them.
In the forecast video on the Met Office web site, Aidan McGivern does mention the showers which seem to be more obvious on the Met Office model, but then puts his foot right in it by adding that classic cliché ‘high pressure in charge’ (fig 3).
This visible image reveals how the BBC graphics have underdone the amount of low cloud across the southeast, the Met Office seem to have done better in its distribution (fig 4).
As for the light showers that are aligned along the weak cold front, both models have underplayed them, the Met Office seem to have made slightly more of them (fig 5).
In the forecast for this lunchtime, I think the Met office and their model did enough to just edged it over the BBC. Next time I do an inter-comparison between the two, I’ll have to choose a day with a bit more weather.
A melting snowman must be one of the saddest sights to any of you snow lovers out there, and especially so to any of you in southwest England, where we only see snow lying every six or seven years or so. This particular snowman was created on Sunday by children and adults alike, but looks to be in a pretty terminal state late this morning, and will be lucky to see the afternoon out! I’ve been watching it as its slumped over from my study winter, and it seemed to be calling me to go up and take its photo for posterity, which I’ve duly done!
Punxsutawney Phil is the name of the groundhog in Punxsutawney, Pennsylvania, who on the 2nd of February this year, saw his own shadow and duly shot back down his hole again knowing full well that there were still six more weeks of Winter to come (fig 1).
A quick glance at the percentiles from the daily temperatures from Central England since then (fig 2), proves that Phil was absolutely right to bolt back down his hole, and miraculously for no reason other than pure chance, his forecast was correct for us even on the other side of the Atlantic.
I am reliably informed that the spring vernal equinox will occur at precisely 1615 UTC today this 20th day of March 2018, but the weather is in a fickle mood at the moment, and spring, well at least the start of it, looks like it will be a cold affair in our part of the world. The Met Office in their extended outlook till the middle of April (fig 1) is being its usual unequivocal self about the possibility.
In line with that outlook, the GFS model for April 1st (fig 2) is forecasting a northerly outbreak which is not at all unusual for spring across the British Isles.
Cold springs are somewhat of a rare commodity these days, and the last one to produce negative anomalies in Central England was back in 2013 (fig 3), and in the last 30 year there have only been three cold springs (2013, 1996 and 1991).
Despite the last record couple of cold days in Central England, I reckon that the average number of degree days between the winter solstice and the vernal equinox was exceeded on the 14th of March this year (fig 1).
This normally would make the first day of spring around a week early, but because springs have been occurring earlier on average (20 days earlier than in 1772 and now around the 11th of March each year), 2018 was around three days late this year, it was also the latest spring to have occurred since 2013.
I personally think that using degree days like this is a crude but effective way of coming up with a date for the start of spring, let me know if you have a better idea.
Yesterday, the 18th of March 2018 was the coldest for that particular day in March since 1853. That’s according to the latest provisional Central England mean temperatures released from the Met Office (fig 1). The maximum for Sunday was 0.6°C and the minimum -2.2°C, and the mean of -0.8°C, was almost 6.6°C lower than the 1961-1990 long-term average of 5.8°C.
Only four other years have reported negative mean temperatures for the 18th of March (fig 2 & 3) in the daily mean CET series that started in 1772, they were 1900, 1853, 1814 and 1812.
Don’t forget that you can keep an eye on the latest daily CET values here
Looking at the observations for yesterday and the reported 06 to 18 UTC maximum temperature (fig 4), many stations across central England and Wales had sub-zero maximums, in fact at a number of stations, the temperature has remained below zero the whole weekend, which just two days from the vernal equinox is highly unusual.
I think the thermograph for the last few days from Rothamsted in Hertfordshire gives a good account of how quickly the cold snap set in last Friday, and just how cold the last 48 hours have been across the country (fig 5).
A slightly premature press release from the Met Office regarding the latest cold spell and today’s snow (fig 1). Maybe it would have been better waiting for tomorrow to release it, in light of the fact that it’s still snowing across large parts of Devon and Cornwall (fig 2).