Has been down to +0.7C with ground frost out of the wind, milky bright sky now and 2.3C
I note sunrise today was 06:12 and sunset will be 18:12 - so why isn't i equinox today?
Apologies for being off topic here, but today is what is known as the equilux when the lengths of the day and night are exactly equal according how we define the official times of sunrise and sunset.
The official definition of sunrise and sunset is when the top of the Sun's disk touches the horizon, allowing for atmospheric refraction which bends the sun's rays slightly, thus causing these events to occur at a slightly different time from what would otherwise be the case. That definition can be simplified by stating that the official time of sunrise and sunset is when the centre of the Sun's disk is about 0.833° below the horizon (i.e. when the Sun's altitude is -0.833°).
This means that the official time of sunrise actually occurs slightly earlier than when it would otherwise occur if we defined that as the exact time when the centre of the Sun's disk was exactly on the horizon without allowing for atmospheric refraction, with the official time of sunset occurring slightly later than what would otherwise be the case.
However, the exact moment when the overhead Sun crosses the Equator which is exact moment of both Equinoxes is when the day and night are equal, only if we go by the times of sunrise and sunset as being when the centre of the Sun's disk crosses the horizon, without allowing for atmospheric refraction. In the case of the vernal Equinox which is when the overhead Sun crosses into the Northern hemisphere, that will occur on this coming Wednesday (20 March 2019) at 9:58pm. Since the time when the centre of the Sun's disk is on the horizon without allowing for atmospheric refraction occur slightly earlier than the official time of sunrise and slightly later than the official time of sunset, this means that the days will actually be slightly longer than the nights on the actual day of the Equinox according to how the official times of sunrise and sunset are defined.
This article will explain that quite well (and probably a lot clearly than what I have attempted to do here).
The north of Edinburgh, usually always missing out on snow events which occur not just within the rest of Scotland or the UK, but also within the rest of Edinburgh.