I was looking forward to getting some snow out of this cold spell. I analysed the charts and it was looking quite good for Ulster.
I honestly expected a covering out of this.
Tuesday, today was progged to have 516dam, -8c 850pha and 300m freezing levels which should surely yield snow at sea level, even at the coast.
Instead, what we have got is 2/3c at sea level, slightly negative dew points but positive wet bulb. So showers are sleety and barely of snow.
The only lying snow of note is above 300m, everything below that level is of a slushy mess.
The cold spell a few weeks ago, which was of -6c 850pha produced sea level snow cover with warmer atmospheric conditions. So why is this cold spell so marginal?
I study all of this and I am fairly interested in it. I can’t establish why colder atmospheric conditions would yield more marginal conditions for snow. Surely a freezing level at 300m would guarantee sea level snow?
Is the atmosphere warmer than predicted?
One thing I notice is that the dew points rise within the shower and drop afterwards. Could this be limiting snowfall?