Detailed Relative Humidity Data
| Current | |
| Measure | Value |
| Relative Humidity | 75% |
| Humidity Trend | +8% /hr |
| 24hr Mean Humidity | 71% |
| Wet-Bulb Temperature | 10.4 °C |
| Absolute Humidity | 8.38 gm-3 |
| Air Density | 1243.31 gm-3 |
| Recent Averages and Extremes | ||
| Measure | Today | Yesterday |
| Minimum | 44% 14:43 |
57% 17:04 |
| Maximum | 95% 07:28 |
95% 06:01 |
| Mean | 70% |
82% |
| Averages, Extremes and Records | ||||||||
| Current | Station Lifetime (09-14) | |||||||
| Measure | 7-day | Month | 31-day | Year | 365-day | Overall | April | 23rd Apr |
| Lowest Min |
36% 17th |
34% 16th |
32% 30th |
32% 15th Mar |
22% 15th Jul |
22% 15th Jul 2013 |
26% Day 19, 2011 |
30% 2011 |
| Highest Max |
98% 21st |
98% 21st |
98% 21st |
98% 5th Jan |
98% 21st Apr |
98% 6th Feb 2009 |
98% Day 29, 2012 |
95% 2012 |
| Highest Min |
75% 20th |
84% 7th |
84% 7th |
96% 30th Jan |
97% 12th Dec |
98% 23rd Dec 2009 |
94% Day 17, 2009 |
56% 2012 |
| Lowest Max |
66% 17th |
66% 17th |
66% 17th |
66% 17th Apr |
56% 2nd May |
56% 20th Jul 2010 |
66% Day 21, 2011 |
77% 2010 |
| Lowest Mean |
54% 17th |
54% 17th |
54% 17th |
52% 9th Mar |
39% 2nd May |
39% 2nd May 2013 |
48% Day 21, 2011 |
52% 2011 |
| Highest Mean |
90% 20th |
91% 6th |
91% 6th |
98% 30th Jan |
98% 12th Dec |
98% 23rd Dec 2009 |
96% Day 11, 2009 |
82% 2012 |
| Averages | ||||||||
| Mean | 70% | 68% | 69% | 77% | 75% | 76% | 68% | 63% |
| Mean Minimum |
48% | 49% | 48% | 59% | 58% | 59% | 48% | 41% |
| Mean Maximum |
86% | 86% | 87% | 90% | 90% | 90% | 86% | 86% |
| Past Year Monthly Averages and Extremes (April 2013 - March 2014) | ||||||||||||
| Extremes | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Jan | Feb | Mar |
| Lowest Min |
31% 7th |
26% 2nd |
34% 14th |
22% 15th |
31% 1st |
40% 1st |
52% 10th |
54% 3rd |
52% 5th |
60% 23rd |
46% 26th |
32% 15th |
| Highest Max |
98% 11th |
97% 25th |
97% 22nd |
95% 30th |
98% 25th |
98% 13th |
98% 3rd |
98% 4th |
98% 10th |
98% 5th |
98% 1st |
98% 1st |
| Highest Min |
83% 11th |
80% 29th |
74% 28th |
72% 30th |
74% 24th |
91% 13th |
89% 3rd |
95% 9th |
97% 12th |
96% 30th |
84% 18th |
77% 3rd |
| Lowest Max |
70% 18th |
56% 2nd |
71% 10th |
66% 15th |
71% 10th |
73% 1st |
73% 10th |
83% 30th |
83% 3rd |
86% 7th |
76% 9th |
69% 9th |
| Lowest Mean |
52% 29th |
39% 2nd |
54% 4th |
41% 15th |
53% 10th |
58% 1st |
66% 10th |
71% 3rd |
68% 6th |
78% 9th |
64% 9th |
52% 9th |
| Highest Mean |
93% 11th |
90% 30th |
87% 28th |
85% 30th |
90% 24th |
96% 13th |
95% 16th |
97% 9th |
98% 12th |
98% 30th |
90% 19th |
90% 3rd |
| Averages | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Jan | Feb | Mar |
| Mean | 66% | 67% | 67% | 61% | 67% | 79% | 85% | 85% | 86% | 88% | 77% | 71% |
| Mean Minimum |
45% | 48% | 50% | 42% | 44% | 60% | 70% | 73% | 76% | 76% | 60% | 48% |
| Mean Maximum |
86% | 85% | 84% | 82% | 88% | 93% | 95% | 95% | 93% | 96% | 90% | 89% |
| Past Year Seasonal Averages | |||
| Season | Daily Min | Daily Max | Mean |
| Winter 13/14 | 71% |
93% |
84% |
| Spring 2013 | 47% |
86% |
68% |
| Summer 2013 | 45% |
85% |
65% |
| Autumn 2013 | 68% |
94% |
83% |
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 | April | 31-day | Year | 365-day |
| Least Humid |
51% Ending 19th Jul 2013 |
60% May 2011 |
62% 2011 |
58% Ending 6th May 2011 |
74% 2011 |
73% Ending 4th Apr 2012 |
| Most Humid |
96% Ending 19th Jan 2010 |
92% Dec 2009 |
74% 2009 |
93% Ending 20th Jan 2010 |
77% 2010 |
79% Ending 7th Apr 2010 |
| Lowest Mean Daily-Min |
32% Ending 19th Jul 2013 |
42% Jul 2013 |
44% 2011 |
40% Ending 15th May 2011 |
59% 2011 |
57% Ending 4th Apr 2012 |
| Highest Mean Daily-Min |
91% Ending 19th Jan 2010 |
84% Dec 2009 |
54% 2009 |
86% Ending 20th Jan 2010 |
62% 2010 |
62% Ending 8th Apr 2010 |
| Lowest Mean Daily-Max |
73% Ending 20th Jul 2013 |
80% May 2011 |
80% 2011 |
77% Ending 7th May 2011 |
88% 2011 |
87% Ending 1st Apr 2012 |
| Highest Mean Daily-Max |
98% Ending 17th Jan 2010 |
97% Dec 2009 |
90% 2009 |
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 | 22% 15th Jul 2013 |
56% 20th Jul 2010 |
39% 2nd May 2013 |
| 2 | 24% 8th Sep 2012 |
56% 2nd May 2013 |
41% 15th Jul 2013 |
| 3 | 26% 19th Apr 2011 |
61% 28th Mar 2012 |
43% 20th Jul 2010 |
| 4 | 26% 2nd May 2013 |
62% 6th Jan 2009 |
43% 28th Mar 2012 |
| 5 | 27% 25th May 2011 |
63% 21st Feb 2013 |
45% 17th Jul 2013 |
| 6 | 27% 28th Mar 2012 |
64% 31st Jan 2009 |
46% 25th May 2011 |
| 7 | 28% 28th Jun 2010 |
65% 2nd Feb 2012 |
47% 28th Jun 2010 |
| 8 | 28% 23rd Jul 2012 |
65% 27th May 2013 |
47% 19th Jul 2010 |
| 9 | 29% 27th Jun 2010 |
66% 19th Jul 2010 |
47% 4th Jul 2011 |
| 10 | 29% 3rd May 2011 |
66% 21st Apr 2011 |
47% 27th May 2013 |
| Most Humid Months | |||
| Rank | Min | Max | Mean |
| 1 | 84% Dec 2009 |
97% Dec 2009 |
92% Dec 2009 |
| 2 | 82% Jan 2010 |
96% Feb 2010 |
90% Jan 2010 |
| 3 | 80% Dec 2010 |
96% Jan 2014 |
89% Feb 2010 |
| 4 | 79% Nov 2011 |
95% Jan 2010 |
89% Nov 2011 |
| 5 | 77% Dec 2012 |
95% Oct 2012 |
88% Dec 2010 |
| 6 | 77% Nov 2010 |
95% Nov 2011 |
88% Jan 2014 |
| 7 | 76% Jan 2013 |
95% Oct 2013 |
87% Dec 2012 |
| 8 | 76% Jan 2011 |
95% Nov 2009 |
87% Nov 2010 |
| 9 | 76% Jan 2014 |
95% Nov 2009 |
87% Jan 2013 |
| 10 | 76% Dec 2013 |
94% Nov 2012 |
86% Nov 2009 |
| Least Humid Months | |||
| Rank | Min | Max | Mean |
| 1 | 42% Jul 2013 |
80% May 2011 |
60% May 2011 |
| 2 | 42% May 2011 |
80% Apr 2011 |
61% Jul 2013 |
| 3 | 44% Apr 2011 |
81% Jul 2010 |
62% Apr 2011 |
| 4 | 44% Aug 2013 |
82% Jul 2013 |
63% Jul 2010 |
| 5 | 45% Jul 2010 |
83% Jun 2010 |
66% Apr 2013 |
| 6 | 45% Apr 2013 |
84% Jun 2013 |
66% Apr 2010 |
| 7 | 46% May 2009 |
84% Jul 2011 |
66% Jul 2011 |
| 8 | 46% Apr 2010 |
84% Apr 2010 |
66% Jun 2010 |
| 9 | 47% Aug 2012 |
85% May 2013 |
67% Aug 2013 |
| 10 | 47% Jun 2010 |
85% May 2010 |
67% May 2013 |
| Most Humid Days in April | |||
| Rank | Min | Max | Mean |
| 1 | 94% Day 17, 2009 |
98% Day 29, 2012 |
96% Day 11, 2009 |
| 2 | 93% Day 11, 2009 |
98% Day 11, 2013 |
96% Day 17, 2009 |
| 3 | 92% Day 12, 2009 |
98% Day 14, 2013 |
95% Day 12, 2009 |
| 4 | 85% Day 28, 2012 |
98% Day 21, 2014 |
94% Day 28, 2012 |
| 5 | 84% Day 7, 2014 |
97% Day 11, 2009 |
93% Day 11, 2013 |
| Least Humid Days in April | |||
| Rank | Min | Max | Mean |
| 1 | 26% Day 19, 2011 |
66% Day 21, 2011 |
48% Day 21, 2011 |
| 2 | 30% Day 23, 2011 |
66% Day 17, 2014 |
50% Day 22, 2011 |
| 3 | 31% Day 6, 2011 |
70% Day 21, 2010 |
51% Day 24, 2010 |
| 4 | 31% Day 21, 2011 |
70% Day 18, 2013 |
52% Day 21, 2010 |
| 5 | 31% Day 22, 2011 |
70% Day 11, 2014 |
52% Day 19, 2011 |
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.