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Detailed Humidity Data

Current/Latest

MeasureValue
Relative Humidity 84%
Rel. Humidity Trend -1% /hr
24hr Average RH 69%
Yesterday Average RH 69%
Week Average RH 73%
Month Average RH 74%
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Dew Point 8.7 °C
Dew Point Trend +0.0 °C /hr
24hr Avg Dew Point 7.7 °C
Yesterday Avg Dew Point 8.6 °C
Week Avg Dew Point 12.9 °C
Month Avg Dew Point 11.5 °C
--- ---
Wet-Bulb Temperature 10.0 °C
Absolute Humidity 6.1 kgm-3
Air Density 1.24 kgm-3

Current Day/Month/Year Records

MeasureValueTime/Date
Min RH Today 77% 00:00
Max RH Today 85% 05:13
Min RH Yesterday 53% 18:16
Max RH Yesterday 88% 02:02
Min RH This Month 34% Day 2
Max RH This Month 97% Day 3
Min RH This Year 24% 23rd June
Max RH This Year 98% Occurs regularly
--- --- ---
Min Dew Point Today 7.6 °C 01:37
Max Dew Point Today 8.7 °C 06:41
Min Dew Point Yesterday 5.8 °C 12:00
Max Dew Point Yesterday 16.1 °C 02:02
Min Dew Point This Month 5.2 °C Day 13
Max Dew Point This Month 17.7 °C Day 11
Min Dew Point This Year -9.3 °C 28th Feb
Max Dew Point This Year 20.9 °C 27th July

All-time Records

MeasureValueTime/Date
Lowest Relative Humidity 24% 23rd June 2018
Highest Relative Humidity 98% Occurs regularly
Lowest RH Daily Mean 39% 2nd May 2013
Highest RH Daily Mean 98% Several instances
Lowest RH Monthly Mean 60% May 2011
Highest RH Monthly Mean 92% Dec 2009
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Lowest Dew Point -9.3 °C 28th Feb 2018
Highest Dew Point 20.9 °C 27th July 2018
Lowest Dew Point Daily Mean -9.7 °C 2nd Feb 2012
Highest Dew Point Daily Mean 19.2 °C 12th May 2016
Lowest Dew Point Monthly Mean -0.5 °C Dec 2010
Highest Dew Point Monthly Mean 13.5 °C July 2018

Note 1: Valid humidity records began in February 2009
Note 2: 98% is the physical limit of the hygrometer (measuring RH); in reality this tends to means 100% saturation of the air

NB: Daily dew point max/mins for the current year (and all other years on record) can be viewed here.
Relative humidity max/mins are here

A note on the different measures of humidity:
The Dew Point (or frost point if the temperature is < 0.0 °Cis the saturation temperature of a parcel of air, i.e. the point at which water condenses out. It is the temperature at which an object would need to be for dew to form on it (dew forms because certain objects - like cars - cool more rapidly than the air, enabling them to reach the dew point). It is directly proportional to the specific humidity, and very well correlated to the absolute humidity. In everyday terms, high dew points are more uncomfortable as sweating is less effective.
Relative Humidity, on the other hand, is rather more abstract and has a very technical definition: the ratio of the partial pressure of water vapour in the air to the saturated vapour pressure of that water. The saturated vapour pressure is proportional to the air temperature, and the partial pressure indicates how much water vapour the air contains, so at a given temperature, the RH is entirely dependent on this partial pressure, making the RH useful in determining the extent to which the air is water-saturated. For example: When it rains the relative humidity will increase, but the dew point may not, as the temperature will usually fall as well. If the dew point is the same when the RH increases, the air has the same amount of water but it is cooler, so it is more saturated, as less water vapour can exist in cooler air.
Simply (and concisely!): Dew point is a rough measure of how much water vapour is physically in the air; relative humidity is just a measure of the degree to which the air is full of water vapour (i.e. its saturation). One is an absolute measure, the other is relative.