Understanding the ways of water is key for meteorologists
Throughout the atmosphere, water in the form of vapour is intermixed with the other gas molecules that make up the air.
The physical processes of condensation (or desublimation/deposition of this water vapour, if the temperature of the air is cooled below 0C (32F)), at constant pressure, give rise to most of the visible weather phenomena: clouds, rain, snow, hoar frost, and dew are examples. For this reason, a thorough understanding of the atmospheric water vapour is fundamental for meteorological purposes.
Water vapour cannot be smelt, seen or tasted.
For anygiven temperature, at constant pressure, air holds only a fixed amount of water vapour. This is expressed as the weight present in a given volume of air, typically grams per cubic metre.
Meteorologists call this very important measurement the "absolute humidity" of the atmosphere. For warmer air, the more moisture it can hold, the cooler the air, the less.
There is a limit to the amount of water vapour that a given volume of air can hold at a constant pressure. When this limiting threshold is reached the air is said to be "saturated".
In general, the air is not saturated; it contains only a fraction of the the quantity of water vapour it has the capacity to hold. This fraction is expressed as a percentage called the "relative humidity" (RH).
For example, air at 10C (50F), if saturated, contains 9.4g of water vapour per cubic metre, and its relative humidity is 100 per cent. However, if it contains only half this amount, 4.7g per cubic metre, the RH is 50 per cent.
When the RH is low, the air is described as "dry", and typically feels brisk and invigorating; if the RH is high, the air is moist or damp; in summer it feels sultry or oppressive, in winter, muggy or raw.
If a parcel of unsaturated air with a known temperature is cooled at constant pressure it will eventually reach a temperature at which it will be saturated. Further cooling will result in the condensation or desublimation/deposition of the excess water vapour.
The temperature that condensation occurs is called the "dew point".
However, in the case of desublimation, where the temperature of the water vapour present in the air is below 0C and is said to exist in a metasable or supercooled state, the term "frost point" is used to describe the manifestation of a hoar frost when saturation occurs.
The frost point is always higher than the dew point.
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Before the introduction of electronic hygrometers it was usual for Stevenson screens to contain a specific type of hygrometer, known as a psychrometer, to measure measure atmospheric humidity.
The device consists of two thermometers. One has a dry bulb, while the bulb of the other is kept moist by being wrapped in wet fabric.
The rate at which the water evaporates from the wet-bulb, that indicates the level of humidity in the air, is betrayed by how fast the bulb cools.
RH can then be found by comparing the readings from the wet-bulb thermometer with those from the dry bulb thermometer. This difference, with the aid of humidity tables, can also be used to determine the water vapour content (absolute humidity), and the dew point.
June 2025 was Wick's warmest since that of 2023.
Closer examination of the burgh's archive for June avouched that is presently the third warmest in a series commencing from 1910.
Wick's precipitation record for June 2025 revealed that it was the wettest since that of 2017, and is currently the third wettest in a series stretching back to 1910.
Wick's mean air temperature for June 2025 was 13.09C (55.56F). The long term average, in terms of the averaging period 1991-2020, is 11.25C (52.25F).
Wick's average daily maximum air temperature for June 2025 was 16.53C (61.75F). The long term average for this parameter, in terms of the current 30 year averaging period, is 14.28C (57.7F). Highest daily maximum was 21C (69.8F), recorded on June 30. Lowest daily maximum was was 12.3C (54.1F), observed on June 7.
The town's average daily minimum air temperature for the month was 9.65C (49.37F), 1.44C higher than the current long term average for June. Highest daily minimum air temperature was 13.7C (56.7F), witnessed on June 28. Lowest daily minimum air temperature was 4.3C (39.7F), noted on June 8.
The lowest temperature recorded at 5cm over the grass was 1.7C (35.1F).
Precipitation occurred on 30 dates. The total amount recorded for the month 102.6mm (4.04 inches), or 185.5 per cent of the current long term average quantity for the month. Wettest day was June 14. The total amount recorded for the 24 hour period commencing 9am (GMT) was 38.4mm (1.51 inches).
June 2025 experienced no "days of gale". However, wind velocities reached or surpassed gale force 8 (39mph/33.9knots) on six dates.
The strongest wind velocity was observed during the hour ending 2pm (GMT) on June 3 when a force 6-7 west-south-west wind gusted up to 51.8mph/45knots, severe gale force 9 on the Beaufort scale.
Electrical storms affected the town on June 22.
Noctilucent clouds were observed on June 29 and 30.