Wet December weather in Wick is not extreme according to records
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Weather Watch by Keith Banks
Isobars and isotherms are lines on weather maps, that represent patterns of equal pressure and temperature respectively. They detail how pressure and temperature are changing, and therefore provide valuable overviews of the large-scale weather regimes developing across a region.
Isobars and isotherms make it easier for meteorologists to interpret and analyse weather maps and help make predictions about the type of weather conditions that are likely to be experienced.
Isobars, lines of constant pressure on a weather chart, are used to identify the positions of areas of low and high pressure, marked L and H on a weather map.
In general, the areas of lowest pressure are where precipitation is most likely to occur.
The areas of high pressure are usually associated with fine, clear and sunny weather. Where the isobars are packed closely together, conditions are windy.
Elongated areas of low pressure are called "troughs", and the extentions or tongues of the areas of high pressure are called "ridges".
Isotherms are lines of constant or equal temperature. Meteorologists use isotherms to highlight areas that have different temperatures.
Typically, isothermal weather maps employ a selection of colours that are used to show the range of temperatures that are affecting a particular region. The purpose of these colour-shaded maps is to show, at a glance, the areas that are the most warm from those that are cooler.
In brief, isobars and isotherms allow meteorologists to view and to assess large-scale evolving weather processes much more easily and effectively than just looking at the raw data.
A review of Wick's archive for mean air temperature for December showed that December 2020 was the most mild since that of 2018, and that it is the 26th mildest in a series starting in 1910.
December 2020 was also the royal burgh's most wet since that of 2017. However, closer scrutiny of the series showed that it is currently the 50th driest since 1910.
December 2020 did not witness any "days of gale".
Wick's mean air temperature for December 2020 was 5.19C (41.34F). The long-term average for December, in terms of the averaging period 1981-2010, is 4.0C (39.20F).
Wick's average maximum daytime air temperature for December 2020 was 6.93C (44.47F), against an average of 6.60C (43.88F).
The highest maximum air temperature was 10.5C (50.9F), on December 18. The lowest maximum was 2.4C (36.3F), recorded on December 28.
Wick's average overnight minimum air temperature for December 2020 was 3.45C (38.21F), while the long-term average for the month is currently 1.40C (34.52F).
The highest overnight minimum air temperature for the month was 8.3C (46.9F), on December 19.
There were nine air frosts.
The lowest ambient air temperature for the month was minus 3.9C (25.0F), noted on December 4.
The temperature fell to 0.0C (32.0F), or lower, at 5cm over the grass, on 12 dates. The lowest temperature recorded over the grass was minus 6.4C (20.5F), on December 4.
Precipitation was measurable on 28 dates.
The total for the month was 71.2mm (2.80 inches), or 94.7 per cent of the long-term average amount for December. The wettest day was December 7. The total for the 24-hour recording period commencing 9am (GMT), for that date, was 19.6mm (0.77in).
Wind velocities reached or exceeded gale force 8 (39.0mph/33.9knots), on five dates. The windiest day was December 13, when a force 7 south-easterly wind gusted up to 51.8mph/45.0knots, during the hour ending 8pm.
Snow was visible over the grass at dawn on December 24 and 29.
