Detailed Relative Humidity Data
| Current | |
| Measure | Value |
| Relative Humidity | 64% |
| Humidity Trend | -4% /hr |
| 24hr Mean Humidity | 85% |
| Wet-Bulb Temperature | 13.5 °C |
| Absolute Humidity | 9.47 gm-3 |
| Air Density | 1212.10 gm-3 |
| Recent Averages and Extremes | ||
| Measure | Today | Yesterday |
| Minimum | 65% 15:16 |
55% 16:21 |
| Maximum | 96% 07:17 |
95% 06:32 |
| Mean | 87% |
82% |
| Averages, Extremes and Records | ||||||||
| Current | Station Lifetime (09-19) | |||||||
| Measure | 7-day | Month | 31-day | Year | 365-day | Overall | May | 19th May |
| Lowest Min |
33% 13th |
33% 13th |
29% 22nd |
29% 21st Apr |
24% 23rd Jun |
21% 25th Mar 2017 |
26% Day 2, 2013 |
31% 2014 |
| Highest Max |
96% Today |
96% 9th |
96% Today |
97% 14th Feb |
98% 25th Dec |
98% 6th Feb 2009 |
98% Day 2, 2014 |
96% Today |
| Highest Min |
71% 17th |
71% 17th |
71% 17th |
90% 24th Jan |
95% 15th Oct |
98% 23rd Dec 2009 |
91% Day 28, 2014 |
65% Today |
| Lowest Max |
87% 14th |
76% 6th |
76% 6th |
76% 6th May |
63% 2nd Jul |
56% 20th Jul 2010 |
56% Day 2, 2013 |
77% 2015 |
| Lowest Mean |
61% 14th |
60% 7th |
52% 21st |
52% 21st Apr |
43% 2nd Jul |
39% 2nd May 2013 |
39% Day 2, 2013 |
54% 2014 |
| Highest Mean |
87% Today |
87% Today |
87% Today |
93% 24th Jan |
96% 15th Oct |
98% 23rd Dec 2009 |
96% Day 28, 2014 |
87% Today |
| Averages | ||||||||
| Mean | 72% | 73% | 70% | 78% | 77% | 75% | 68% | 70% |
| Mean Minimum |
49% | 51% | 49% | 62% | 60% | 59% | 48% | 47% |
| Mean Maximum |
91% | 91% | 88% | 90% | 90% | 89% | 86% | 89% |
| Past Year Monthly Averages and Extremes (May 2018 - April 2019) | ||||||||||||
| Extremes | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Jan | Feb | Mar | Apr |
| Lowest Min |
28% 7th |
24% 23rd |
27% 2nd |
28% 6th |
29% 27th |
46% 1st |
60% 8th |
63% 12th |
54% 28th |
32% 25th |
40% 10th |
29% 21st |
| Highest Max |
97% 31st |
94% 4th |
95% 14th |
96% 26th |
97% 3rd |
98% 16th |
98% 6th |
98% 5th |
96% 25th |
97% 14th |
97% 10th |
95% 9th |
| Highest Min |
85% 29th |
74% 4th |
69% 29th |
70% 22nd |
77% 22nd |
95% 15th |
93% 16th |
89% 5th |
90% 24th |
88% 1st |
80% 6th |
84% 7th |
| Lowest Max |
73% 15th |
70% 24th |
63% 2nd |
78% 8th |
83% 14th |
79% 13th |
85% 3rd |
86% 14th |
81% 14th |
85% 26th |
79% 28th |
77% 23rd |
| Lowest Mean |
54% 7th |
51% 25th |
43% 2nd |
56% 6th |
62% 27th |
66% 1st |
77% 3rd |
76% 14th |
73% 28th |
66% 25th |
66% 11th |
52% 21st |
| Highest Mean |
92% 29th |
86% 4th |
84% 29th |
90% 26th |
87% 12th |
96% 15th |
95% 16th |
94% 27th |
93% 24th |
93% 1st |
86% 3rd |
90% 7th |
| Averages | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Jan | Feb | Mar | Apr |
| Mean | 71% | 68% | 62% | 72% | 73% | 81% | 87% | 87% | 83% | 82% | 77% | 72% |
| Mean Minimum |
50% | 47% | 41% | 52% | 52% | 67% | 77% | 79% | 74% | 67% | 60% | 52% |
| Mean Maximum |
90% | 87% | 85% | 89% | 90% | 92% | 94% | 93% | 90% | 93% | 89% | 87% |
| Past Year Seasonal Averages | |||
| Season | Daily Min | Daily Max | Mean |
| Winter 18/19 | 73% |
92% |
84% |
| Spring 2018 | 54% |
89% |
73% |
| Summer 2018 | 47% |
87% |
68% |
| Autumn 2018 | 65% |
92% |
80% |
View daily tables of
min /
max /
mean
Humidity data for the past year
View monthly tables of
min /
max /
mean
Humidity data for all months in the station history.
| Record Period Averages | ||||||
| Measure | 7-day | Month | May | 31-day | Year | 365-day |
| Least Humid |
50% Ending 9th May 2016 |
60% May 2011 |
60% 2011 |
58% Ending 6th May 2011 |
73% 2016 |
71% Ending 17th Jul 2017 |
| Most Humid |
96% Ending 27th Nov 2014 |
92% Dec 2009 |
73% Current |
93% Ending 20th Jan 2010 |
78% 2019 |
79% Ending 7th Apr 2010 |
| Lowest Mean Daily-Min |
32% Ending 19th Jul 2013 |
41% Jul 2018 |
42% 2011 |
37% Ending 21st Jul 2018 |
57% 2015 |
56% Ending 11th Jul 2015 |
| Highest Mean Daily-Min |
92% Ending 27th Nov 2014 |
84% Dec 2009 |
54% 2012 |
86% Ending 20th Jan 2010 |
62% 2010 |
62% Ending 20th Jun 2018 |
| Lowest Mean Daily-Max |
73% Ending 25th Apr 2017 |
76% Apr 2017 |
80% 2011 |
76% Ending 30th Apr 2017 |
85% 2016 |
82% Ending 2nd Sep 2017 |
| Highest Mean Daily-Max |
98% Ending 17th Jan 2010 |
97% Dec 2009 |
91% Current |
97% Ending 28th Dec 2009 |
91% 2009 |
92% Ending 1st Mar 2010 |
Ranked Historical Humidity Data
| Most Humid Days | |||
| Rank | Min | Max | Mean |
| 1 | 98% 23rd Dec 2009 |
98% 6th Feb 2009 |
98% 23rd Dec 2009 |
| 2 | 98% 24th Dec 2009 |
98% 9th Feb 2009 |
98% 24th Dec 2009 |
| 3 | 98% 30th Dec 2009 |
98% 10th Feb 2009 |
98% 30th Dec 2009 |
| 4 | 98% 14th Jan 2010 |
98% 13th Feb 2009 |
98% 14th Jan 2010 |
| 5 | 98% 15th Jan 2010 |
98% 7th Aug 2009 |
98% 15th Jan 2010 |
| 6 | 98% 29th Dec 2010 |
98% 8th Aug 2009 |
98% 29th Dec 2010 |
| 7 | 98% 22nd Oct 2012 |
98% 15th Sep 2009 |
98% 30th Dec 2010 |
| 8 | 98% 23rd Oct 2012 |
98% 16th Sep 2009 |
98% 20th Nov 2011 |
| 9 | 98% 11th Feb 2013 |
98% 7th Oct 2009 |
98% 21st Nov 2011 |
| 10 | 98% 8th Mar 2013 |
98% 10th Oct 2009 |
98% 22nd Oct 2012 |
| Least Humid Days | |||
| Rank | Min | Max | Mean |
| 1 | 21% 25th Mar 2017 |
56% 20th Jul 2010 |
39% 2nd May 2013 |
| 2 | 22% 15th Jul 2013 |
56% 2nd May 2013 |
41% 5th May 2016 |
| 3 | 22% 18th Jul 2016 |
61% 28th Mar 2012 |
41% 15th Jul 2013 |
| 4 | 24% 8th Sep 2012 |
62% 6th Jan 2009 |
43% 20th Jul 2010 |
| 5 | 24% 30th Jun 2015 |
63% 21st Feb 2013 |
43% 28th Mar 2012 |
| 6 | 24% 10th Jul 2015 |
63% 2nd Jul 2018 |
43% 2nd Jul 2018 |
| 7 | 24% 19th Jul 2015 |
64% 31st Jan 2009 |
44% 10th Jul 2015 |
| 8 | 24% 23rd Jun 2018 |
65% 2nd Feb 2012 |
44% 1st Jul 2015 |
| 9 | 25% 19th Apr 2018 |
65% 27th May 2013 |
45% 17th Jul 2013 |
| 10 | 25% 25th Jun 2018 |
65% 1st Jul 2015 |
45% 30th Jun 2015 |
| Most Humid Months | |||
| Rank | Min | Max | Mean |
| 1 | 84% Dec 2009 |
97% Dec 2009 |
92% Dec 2009 |
| 2 | 82% Jan 2010 |
96% Nov 2014 |
90% Nov 2014 |
| 3 | 81% Nov 2014 |
96% Feb 2010 |
90% Jan 2010 |
| 4 | 80% Dec 2010 |
96% Jan 2014 |
89% Feb 2010 |
| 5 | 79% Dec 2017 |
95% Jan 2010 |
89% Nov 2011 |
| 6 | 79% Dec 2018 |
95% Oct 2012 |
88% Dec 2010 |
| 7 | 79% Nov 2011 |
95% Nov 2011 |
88% Jan 2014 |
| 8 | 77% Dec 2012 |
95% Oct 2013 |
88% Dec 2017 |
| 9 | 77% Nov 2010 |
95% Nov 2009 |
87% Dec 2018 |
| 10 | 77% Nov 2018 |
95% Nov 2009 |
87% Dec 2012 |
| Least Humid Months | |||
| Rank | Min | Max | Mean |
| 1 | 41% Jul 2018 |
76% Apr 2017 |
60% May 2011 |
| 2 | 42% Jul 2013 |
79% Jun 2017 |
60% Apr 2017 |
| 3 | 42% May 2011 |
80% May 2011 |
61% Jun 2015 |
| 4 | 42% Jun 2015 |
80% Apr 2011 |
61% Jul 2013 |
| 5 | 43% Jul 2014 |
80% Apr 2011 |
62% Apr 2011 |
| 6 | 43% Jul 2015 |
80% Jun 2015 |
62% Jul 2018 |
| 7 | 44% Jun 2014 |
80% Jul 2017 |
63% Jul 2015 |
| 8 | 44% Apr 2015 |
81% Jul 2010 |
63% Jul 2010 |
| 9 | 44% May 2015 |
82% Jul 2015 |
63% Jun 2017 |
| 10 | 44% Apr 2011 |
82% Dec 2016 |
64% May 2015 |
| Most Humid Days in May | |||
| Rank | Min | Max | Mean |
| 1 | 91% Day 28, 2014 |
98% Day 2, 2014 |
96% Day 28, 2014 |
| 2 | 90% Day 3, 2012 |
98% Day 28, 2014 |
94% Day 27, 2014 |
| 3 | 89% Day 27, 2014 |
97% Day 1, 2012 |
92% Day 29, 2018 |
| 4 | 85% Day 29, 2018 |
97% Day 10, 2012 |
92% Day 3, 2012 |
| 5 | 83% Day 10, 2012 |
97% Day 25, 2013 |
92% Day 10, 2012 |
| Least Humid Days in May | |||
| Rank | Min | Max | Mean |
| 1 | 26% Day 2, 2013 |
56% Day 2, 2013 |
39% Day 2, 2013 |
| 2 | 27% Day 25, 2011 |
65% Day 27, 2013 |
41% Day 5, 2016 |
| 3 | 27% Day 8, 2016 |
66% Day 1, 2011 |
45% Day 8, 2016 |
| 4 | 28% Day 5, 2016 |
67% Day 20, 2011 |
46% Day 25, 2011 |
| 5 | 28% Day 7, 2018 |
67% Day 5, 2016 |
47% Day 27, 2013 |
Notes:
- Valid humidity records began in February 2009
- All figures, unless specified, relate to the period midnight-midnight, this being when daily extremes are reset
- 98% is the physical limit of the hygrometer (measuring RH); in reality this tends to means 100% saturation of the air. This value is achieved fairly frequently, any record with this value is just the first instance it occurred in the relevant timeframe.
The different measures of humidity:
The Dew Point (or frost point if the temperature is < 0.0 °C
is 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.