Wet bulb temperatures offer valuable insights into atmospheric moisture and human comfort levels.

It plays a vital role in climate monitoring and helps explain the impact of humidity on daily life.

One of the most traditional and widely used measures of humidity is the wet bulb temperature.

The Met Office say: “This value provides insight into how saturated the air is and is essential for calculating other humidity-related variables such as relative humidity and dew point temperature.”

What is a wet bulb temperature?

Measured using a thermometer wrapped in a damp muslin wick, wet bulb temperature represents the lowest temperature achievable through evaporative cooling.

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The reading drops as water evaporates from the wick, drawing heat from the thermometer. This cooling continues until the air becomes saturated and can absorb no more moisture.

On foggy mornings or in fully saturated air, wet bulb temperature matches the dry bulb temperature—the actual air temperature.

In all other conditions, the wet bulb reading is lower.

The underlying principle is simple: evaporation requires energy.

Water vapour draws heat from the surrounding air and thermometer, leading to a cooler reading.

The larger the gap between dry bulb and wet bulb temperatures, the drier the air.

When there is no difference, the air is fully saturated and evaporation stops.

Traditionally, wet bulb temperature is measured using a psychrometer—an instrument with paired dry and wet bulb thermometers.

However, most modern weather stations no longer use this classic setup.

“Instead, they rely on two separate thermometers housed in a Stevenson screen: one dry bulb (measuring air temperature) and one wet bulb (wrapped in a moist wick connected to a water reservoir).”

Air moves over both thermometers, allowing evaporation from the wet bulb and resulting in evaporative cooling.

The dry bulb remains unchanged.

The temperature difference helps meteorologists calculate relative humidity and other important humidity metrics.

Modern technology has introduced capacitive sensors to the process.

These sensors measure humidity by detecting voltage changes caused by varying amounts of water vapour in the air.

Readings are then converted into relative humidity or dew point values, providing an automated and more precise method of measurement.

Wet bulb temperature is closely tied to other indicators, such as dew point temperature—the point at which air becomes saturated and moisture begins to condense.

On cool mornings, this is seen as dew forming on grass.

If the dew point or wet bulb temperature equals the air temperature, relative humidity is 100 per cent.

Both values are critical for understanding atmospheric moisture.

They enable meteorologists to assess the likelihood of rain, fog, or heat stress for people and animals.

The Met Office added: “Wet bulb temperature remains a fundamental tool in meteorology for assessing humidity and its effects on weather, climate, and human health.

“Whether measured using traditional psychrometers or advanced sensors, it provides valuable insights into atmospheric conditions.

“By understanding and monitoring wet bulb temperatures, the Met Office continues to deliver accurate forecasts and support public safety across a wide range of sectors.”

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The reception, held at the Oxfordshire base, brought together serving personnel, RAF representatives, and community leaders for a blend of ceremony and refined hospitality.

Guests gathered outside the Officers’ Mess as the Band of the RAF Regiment set the tone with a musical performance beneath the summer evening sky.

The ceremonial proceedings began with a display from the Ceremonial Flight, led by Flight Lieutenant Matt Thornton, followed by a General Salute.

Two 28 (AC) Squadron Chinook aircraft performed a low-level flypast, drawing all eyes skyward.

The event was attended by a range of dignitaries, including the Mayor of Wallingford, Vincent Cervoni, and representatives from parish and county councils, schools, and local organisations.

Following the ceremony, guests enjoyed drinks and canapés on the terrace before addresses from Station Commander Wing Commander Alice Tierney and Commander Air Wing Wing Commander Johnny Longland.

As the evening drew to a close, His Majesty’s Representative, the Deputy Lieutenant, departed, signalling the end of the formal proceedings.

The Officers’ Mess bell was rung at 8pm to mark the handover between the outgoing and incoming President of the Mess Committee – Squadron Leader Rawson to Squadron Leader Welch.

It also marked the final reception in service uniform for WO Evans.

The event was organised by a team led by Project Officer Flight Lieutenant Charles Ihe, whose attention to detail was widely praised.

The students, from the Falkland Islands Community School, are settling into life at Burford School, one of the oldest schools in the country.

Staff have praised the ‘excellent first impression’ they have made so far, noting how quickly the group has unpacked and familiarised themselves with the routines of the boarding house.

The school noted: “The buildings and setting have made a particularly strong impression.

“The Year 10 arts students wish to express our sincere gratitude to the individuals and companies whose generous sponsorship and support made this opportunity possible.”

Burford School, founded in 1571 by the townsmen of Burford with merchant Simon Wysdom at their helm, initially offered an education to the sons of the ordinary men of Burford, charging four pence for enrolment and a further eight pence for schooling per year.

The school began taking girls in 1924, thanks to the generosity of Elmslie John Horniman, and has now grown to just over 1,500 students.

Today, its community includes 100 boarders from the surrounding region and abroad.

Although the school no longer operates its once-successful farm, it continues to maintain a ‘strong rural feel’.

More than 450 years after its founding, Burford School remains, in its own words, ‘popular and successful’.

Both staff and students said they are ‘immensely proud’ to be part of Burford School.