July 2009 Print

My July

Temperature: With a mean temperature for the month of 5.5C, this July was the coldest since 2004 and just below the average for the past 9 years of 5.6C. The warmest day was the 31st with 19.3C, the second warmed July day I've recorded. My record is 19.6C on the 26th and 27th July 2007. Coldest temperature was -3.9C on the 14th, the coldest temperature this year to date. The coldest July temperature I've recorded is -6.9C on 3rd July 2001. There were 3 days where the temperature was at or over 15C, right on my July average of 3. There were 11 days where the minimum temperature was at or below 0 equal to my July average. July 2001 holds my record for 23 days where the minimum temperature was at or below 0. [Frost days corrected 1 Aug 2010]

Wind: (Records from 2001) The monthly wind run of 2784km is 79% of my July average of 3505km and the least windy July I've recorded. July 2008 the windiest with 4724km, 134% of average. The 7th recorded just 9km of wind run, the 4th lowest wind run recorded to date this year and the lowest for a July day.

Rainfall: July had 40.4mm of rain over 11 days, 58% of the average of 70mm over 12 days and was the 4th driest I've recorded. The driest was 2000 with 18.8mm over 15 days, the wettest, 2008 with 195.4mm over 18 days.

Barometer: (Records from 2006) The average pressure for the month was below the average of 1013.8 hPa with 1007.7 hPa. The lowest pressure was recorded on the 23rd, 984.2 hPa. The lowest minimum pressure for July I've recorded. The highest pressure was 1028.7, the lowest maximum for July.

July 2009 Summary
Temperature
Mean 5.5 C
Mean Maximum 10.2 C
Mean Minimum 1.4 C
Maximum High 19.3 C (31st)
Maximum Low 8.1 C (23rd)
Minimum High 6.6 C (3rd)
Minimum Low -3.9 C (14th)
Wind Speed and Direction
Maximum Gust 51 km/h (24th)
Mean 3.9 km/h
Wind Run 2784 km
Max Daily Windrun 250 km (24th)
Prevailing Direction East Nth East
Barometer
Maximum 1028.7 hPa (9th)
Minimum 984.2 hPa (23rd)
Mean 1007.7 hPa
Max Daily Change +26.0 hPa (24th)
Rainfall
Days with Measured Rainfall (Greater than 0.2mm) 11
Max Daily Rainfall 12.4 mm (2nd)
Monthly Rainfall 40.4 mm
Humidity
Maximum 92 % (Several Days)
Minimum 35 % (22nd)

July Daily Observations
Temperature Wind Rainfall Barometer
Date Min Max Mean Mean
(Km/h)		 Gust
(Km/h)		 Run (km) Prevailing Dir 10 Minute Max (mm) Total (mm) Min (hPa) Max (hPa) Change (hPa)
1 3.3 7.8 4.8 1.2 14 28 West Sth West 0.2 2.6 1014.3 1016.8 -2.5
Overcast with morning drizzle and light rain. Light breezes.
2 2.1 7.8 5.3 6.2 38 144 East Nth East 1.4 12.4 1006.1 1014.4 -8.3
Cloud increasing in the morning with some light rain. Ran from evening with NE winds.
3 2.4 6.6 4.8 5.9 29 136 West Sth West 0.4 7.6 994.1 1006.9 -12.8
Showers clearing by dawn, overcast with southerly winds.
4 3.7 8.7 6.1 8.0 33 185 West Sth West 0.2 0.6 995.0 996.8 +1.8
Cloud breaking for a time in the morning but remaining overcast for much of the day. Light rain in the evening.
5 2.6 8.1 5.7 0.8 20 18 East Sth East 0.2 0.4 995.4 1001.2 +5.8
Overcast with showers early morning and a few spots of rain during the day. Light easterly winds.
6 2.2 7.7 4.9 3.3 24 75 East Nth East 0.2 0.6 1001.1 1004.1 +3.0
Overcast with NE breezes, showers in the evening.
7 1.7 7.9 4.7 0.4 9 9 East Nth East 0.4 6.6 1004.4 1017.1 +12.7
Showers clearing mid morning. Overcast for most of the day but cloud breaking and clearing from late afternoon. Light breezes.
8 0.0 8.9 4.7 1.8 19 40 West Sth West 0.2 0.2 1017.1 1025.3 +8.2
Early morning shower. Cloud clearing to a sunny day with light southerly breezes.
9 -0.1 10.9 5.2 1.7 21 38 South Sth West 0 0 1025.1 1028.7 +3.6
Sunny with light breezes, frosty evening.
10 0.4 9.7 5.3 1.0 14 23 West Sth West 0 0 1024.3 1027.5 -3.2
Morning cloud clearing late morning to a sunny day with light breezes.
11 -1.0 10.3 3.7 1.2 12 29 West Sth West 0.2 0.8 1018.4 1024.4 -6.0
Morning frost. Few clouds but mostly clear and sunny with light southerly breezes.
12 1.5 7.2 4.0 3.6 29 84 West Sth West 0.2 1.6 1015.5 1018.5 -3.7
Sunny for a time in the morning. Cloud increasing with showers and cold southerly winds.
13 -0.7 6.7 2.9 2.1 19 48 East Nth East 0.2 0.4 1005.6 1016.4 -10.8
Early morning showers then a frost made roads and foot paths slippery. Overcast with high cloud for mush of the day, clearing in the evening. NE breeze.
14 -3.9 9.0 2.1 1.5 15 35 East Nth East 0 0 996.6 1005.5 -8.9
Frost. High cloud with weak sun, cloud increasing later in the afternoon. Light NE breezes. Lowest temperature of the year to date and colder then 2008's lowest temperature of -3.5C.
15 0.2 7.6 4.4 4.1 26 94 West Sth West 0 0 997.0 1009.7 +12.7
Early light showers. Overcast with a cool southerly breeze.
16 4.1 7.2 5.5 1.3 14 31 West Sth West 0 0 1008.6 1014.1 +5.5
Overcast with light southerly breezes.
17 3.1 10.2 6.3 4.4 24 100 East Nth East 0.2 0.2 1001.7 1013.1 -11.4
Morning cloud with a late shower. Cloud breaking in the afternoon and sunny for a time. Light NE winds turning southerly in the afternoon.
18 1.1 9.8 4.1 2.1 31 49 East Nth East 0.2 0.2 985.0 1002.0 -17.0
Morning fog lifting about midday. Clear and sunny afternoon with light NE breezes. Late southerly change.
19 -1.1 9.8 5.5 5.9 36 135 South Sth West 0 0 988.4 1003.8 +15.4
Morning cloud clearing to a sunny day with cool southerly wind.
20 -3.3 10.7 3.6 3.6 20 83 East Nth East 0 0 1004.2 1014.2 +10.0
Morning frost, clear and sunny with light NE wind.
21 3.6 16.1 8.1 6.4 49 148 East Nth East 0 0 991.5 1012.1 -20.6
Mostly overcast with NE winds turning nor'west in the afternoon with a few light showers. Strong southerly change at night.
22 0.0 16.0 7.1 3.9 35 91 West Nth West 0 0 995.7 1003.1 +7.4
Morning frost. Clear and sunny with mild nor'west winds in the afternoon.
23 8.1 14.0 10.4 5.4 41 125 East Nth East 0 0 984.2 1001.4 -17.2
Overcast with high cloud, north to NE winds. A southerly change late evening.
24 2.7 9.4 5.8 10.8 51 250 South Sth West 0.8 5.4 991.1 1017.1 +26.0
Squally showers in the morning, some with hail. Cold southerly winds easing in the afternoon and cloud breaking in the evening.
25 -2.3 10.7 4.3 2.9 21 68 East Nth East 0 0 1017.3 1020.7 +3.4
Morning frost, clear and sunny with a cool NE breeze.
26 -1.1 10.8 4.0 2.5 19 58 East Nth East 0 0 1017.3 1019.8 +2.5
Morning frost, some thin high cloud but mostly sunny with NE breezes.
27 -3.8 9.2 3.3 5.5 30 126 East Nth East 0 0 1012.6 1019.6 -7.0
Good frost, second coldest morning of the year to date. Mostly sunny with some thin high cloud at times. NE wind picking up in the evening.
28 5.8 10.8 8.1 8.5 26 196 East Nth East 0 0 1002.6 1012.8 -10.2
Overcast with NE wind.
29 1.6 12.9 7.1 4.1 22 94 East Nth East 0 0 999.7 1008.4 -8.7
Clear and sunny morning, cloud increasing in the afternoon. North to NE winds.
30 4.4 13.1 7.9 3.8 26 89 East Nth East 0 0 997.9 1004.3 +6.4
Mostly sunny, high cloud increasing late afternoon. Light NE winds.
31 5.4 19.3 11.2 6.0 41 138 East Nth East 0 0 995.0 1002.8 -7.8
Gusty nor'west winds in the afternoon with mild temperatures. The second warmest July day in my records behind 19.6C on July 27th 2007.
July 2009 Temperature Graph July 2009 Wind Dir Graph July 2009 Wind Dir % Graph July 2009 Wind Speed Graph July 2009 Rainfall Graph July 2009 Barograph July 2009 Humidity Graph
 

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