Thursday, 1 March 2007 - Monthly Climate Summary for Tasmania - Product code IDCKGC17R0

Tasmania in February 2007:
Very warm and mostly dry – but locally very wet

Summary

February 2007 was an exceptionally warm month in Tasmania, with several records broken. It was also quite dry – except in those places in the northeast and southeast affected by the several heavy showers and thunderstorms that developed through the month.

A separate summary has also been prepared for the whole of summer 2006/07.

Details

Hot spells: The second half of the month brought long periods of very warm temperatures. For example, Launceston reported fifteen days in a row over 26°C, and an unprecedented nine straight days reaching 28°C. Launceston had a total of eleven days reaching 28°C; in a normal February this occurs on about four days.
As is often the case, Hobart's temperatures were more varied than Launceston's. But Hobart did have three days in a row reaching 31°C, and a highest temperature of 35.2°C (although Dover's 36.8°C was the hottest in the state). Such a hot spell in Hobart has happened in only twice in February since 1896, and only nine times all up – most recently in December 1994.

Very few cold days: As well as some very warm days, there were very few especially cool days. Hobart's coldest day reached 16.8°C; in a normal February there are about four days that don't reach 17°C. At Bushy Park in the Derwent Valley, every day reached 22.8°C or higher (at Cressy and Ouse every day reached 22.4°C or higher); these are the first times in Tasmania where a station has had every day in a month above 22 °C.

Record warm days: With lots of warm days, several hot ones, and very few cool ones it is not surprising that some sites (including Launceston and Strathgordon) had their highest February mean daily maximum temperature on record. Averaged across the month, maximum temperatures were over 3°C above normal in the west and the northern Midlands, about 2°C above normal along the north coast, but close to normal along the east coast.

Very mild nights: Mild nights were very common through the month. After a cold first morning where a few places dropped below freezing, there were very few cool nights. For example, Launceston had sixteen nights (including an unprecedented twelve in a row) where the temperature did not drop below 15°C; there is normally only about five such mild nights in February. Hobart had twelve nights above 15°C against a February normal of around four. Burnie had a record six nights where the temperature did not drop below 20°C.
Minimum temperatures averaged across the month were above normal, by about 1°C in the south but by over 3°C in the northeast third of the state. Many sites in the north and east (including Launceston, Burnie and Swansea) had their  highest February mean daily minimum temperature on record, or their highest since 1972. Flinders Island Airport, Marrawah and Wynyard had their warmest February night on record.

Not much rain...: With only one major cold front crossing the state during the month, rainfall was well down on normal in most areas. Most sites in the western highlands had their lowest February rainfall on record.  Mount Read, often the wettest spot in the state, received only 30 mm for the whole month. Several sites in the far northwest received less than 10 mm, and Smithton got less than 5 mm for the month. 

...but some local very heavy falls: Several times during the month there were very heavy – but very localised – showers and thunderstorms. On the 10th, thunderstorms gave up to 50 mm to some spots in the northeast. On the 16th, it was the southeast that saw the biggest storms, with falls around 20 mm reported, and more thunderstorms were seen on the 17th and the 18th. The 22nd brought more thunderstorms to the north and northeast; Mount Barrow received 75 mm. There were more storms in the southeast on the 24th, and the month ended with local heavy rain in the northeast, including 80 mm in 24 hours at Gray. These storms mostly delivered their rain in just a few hours but to only small areas; flash flooding was reported as a result. A few sites in the northeast had their wettest February for many years

Persistent ridging and few fronts: There were high pressure systems sitting to the east and south of Tasmania for much of February. These prevented cold fronts and low pressure systems from crossing the state (with the notable exception of one on the 19th), so there statewide rain was rare. The highs also directed warm air over Tasmania, bringing the recurrent warm days and the mild nights. Wind were often easterly, pushing temperatures especially high in the western half. Sometimes the air was warm, humid and unstable, allowing thunderstorms to develop, particularly in the northeast and the southeast. 

Further information

Ian Barnes-Keoghan or Tom Delfatti
Tasmania and Antarctica Climate Services Centre
Bureau of Meteorology
Phone (03) 6221 2043
Email climate.tas@bom.gov.au

Extremes

Hottest day
Highest temperature
36.8°C at Dover on the 18th
Warmest days on average
Highest mean daily maximum temperature
27.6°C at Ouse and Cressy
Coolest days on average
Lowest mean daily maximum temperature
15.9°C at Mount Wellington
Coldest day
Lowest daily maximum temperature
8.2°C at Mount Wellington on the 11th
Coldest night
Lowest temperature
−1.5°C at Liawenee on the 1st
Coolest nights on average
Lowest mean daily minimum temperature
7.3°C at Mount Wellington
Warmest nights on average
Highest mean daily minimum temperature
17.0°C at Burnie
Warmest night
Highest daily minimum temperature
21.4°C at Flinders Island Airport on the 18th
Wettest overall
Highest total rainfall
223.2 mm at Gray (Craigie-Lea)
Driest overall
Lowest total rainfall
4.8 mm at Smithton Aerodrome
Wettest day
Highest daily rainfall
80.4 mm at Gray (Craigie-Lea) on the 28th
Highest wind gust
115 km/h at Hogan Island on the 10th

Records


Record lowest total February rainfall
Total rainfall
for February 2007 (mm)
Previous lowest
for February
Years of
record
Normal for
February
Maatsuyker Island Lighthouse 10.0 13.7 in 1901 116 70.1
Waratah (Mount Road) 10.2 14.5 in 1912 105 93.1
Lake Margaret Power Station 34.6 41.3 in 1956 63 141.3
Savage River Mine 12.2 16.0 in 1991 39 78.8
Strathgordon Village 15.8 43.1 in 1975 39 108.7
Zeehan (West Coast Pioneers Museum) 17.8 32.4 in 1983 39 99.7
Port Davey (Melaleuca) 13.6 34.4 in 1956 38 120.8
Marrawah 7.2 8.2 in 1983 37 43.5


Lowest total February rainfall for at least 20 years
Total rainfall
for February 2007 (mm)
Most recent lower
for February
Years since
lower
Normal for
February
Cape Sorell 11.4 10.9 in 1916 66 68.5
Macquarie Island 47.4 45.0 in 1966 41 84.9
Cape Bruny Lighthouse 16.2 15.0 in 1981 26 56.5




Highest total February rainfall for at least 20 years
Total rainfall
for February 2007 (mm)
Most recent higher
for February
Years since
higher
Normal for
February
Pyengana (Forest Lodge Road) 156.4 200.3 in 1969 38 62.9
Gray (Craigie-Lea) 223.2 283.3 in 1971 35 78.7
Lady Barron (Franklin Parade) 57.2 116.8 in 1978 28 39.6
Cape Barren Island School 80.6 96.5 in 1978 26 36.7




Record highest February mean daily maximum temperature
Mean daily maximum
temperature
for February 2007 (°C)
Previous highest
for February
Years of
record
Normal for
February
Launceston Airport Comparison 26.5 26.2 in 2001 68 23.1
Strathgordon Village 23.9 23.7 in 1971 38 19.5
Marrawah 24.0 23.4 in 1983 35 20.7
Launceston (Ti Tree Bend) 27.3 26.5 in 2000 24 24.3
Tarraleah Village 23.4 22.9 in 2000 23 19.7
Wynyard Airport 23.4 22.8 in 2001 22 21.3

Highest February mean daily maximum temperature for at least 20 years
Mean daily maximum
temperature
for February 2007 (°C)
Most recent higher
for February
Years since
higher
Normal for
February
Maatsuyker Island Lighthouse 19.5 20.1 in 1972 35 17.2


Record highest February temperature
Highest temperature
in February 2007 (°C)
Previous highest
for February
Years of
record
Normal for
February
Geeveston (Cemetery Road) 36.6 on the 18th 36.5 on the 25th in 1995 22 22.0




Record highest February mean daily minimum temperature
Mean daily minimum
temperature
for February 2007 (°C)
Previous highest
for February
Years of
record
Normal for
February
Launceston Airport Comparison 13.2 12.9 in 1956 68 10.3
Burnie (Round Hill) 17.0 16.2 in 1956 58 13.1
Swansea Post Office 14.7 14.3 in 1999 51 11.7
Eddystone Point 16.7 16.1 in 1971 50 14.1
Flinders Island Airport 16.1 15.4 in 1999 44 13.6
Scottsdale (West Minstone Road) 14.5 13.3 in 2000 35 11.0
Bicheno (Council Depot) 15.3 = 15.3 in 1972 33 12.9
Launceston (Ti Tree Bend) 15.0 13.7 in 1999 24 11.9
Scamander 15.8 14.3 in 2001 23 12.7
Wynyard Airport 15.0 13.5 in 1999 22 11.2
Fingal (Legge Street) 12.6 12.5 in 1999 21 9.8


Highest February mean daily minimum temperature for at least 20 years
Mean daily minimum
temperature
for February 2007 (°C)
Most recent higher
for February
Years since
higher
Normal for
February
Cape Bruny Lighthouse 14.0 14.7 in 1972 35 11.7
Maatsuyker Island Lighthouse 13.0 14.0 in 1972 34 11.0
Bicheno (Council Depot) 15.3 15.3 in 1972 25 12.9



Record highest February daily minimum temperature
Highest daily minimum
temperature
in February 2007 (°C)
Previous highest
for February
Years of
record
Normal for
February
Flinders Island Airport 21.4 on the 18th = 21.4 on the 8th in 1975 45 13.6
Marrawah 20.6 on the 18th 19.8 on the 3rd in 2001 36 12.3
Wynyard Airport 20.2 on the 22nd 20.0 on the 24th in 1967 21 11.2


Summaries

In the following table, some key sites have been highlighted to make them easier to find.


Summary statistics for February 2007
Maximum temperatures
for February
(°C)
Minimum temperatures
for February
(°C)
Rainfall
for February
(millimetres)
Mean for
February
2007
Diff
from
normal
Highest for
February
2007
Mean for
February
2007
Diff
from
normal
Lowest for
February
2007
Total for
February
2007
Normal
for
February
Rank of
February
2007
Fraction of
February
normal
Northern (district 91)
Bridport 23.8 +1.6 27.9 22nd 15.7 +2.6 10.9 8th 39.0 30.4 normal 128%
Burnie 23.1 +2.0 25.7 16th 17.0 +3.9 12.4 3rd 15.6 45.8 low 34%
Cape Grim BAPS 21.9 +2.4 28.0 17th 15.0 +1.3 9.5 1st 13.2 34.4 low 38%
Cressy Research Station 27.6 34.8 17th 13.1 3.4 1st 6.2
Devonport Airport 23.3 +2.0 27.2 22nd 15.6 +3.3 10.3 1st 18.2 36.4 normal 50%
Launceston 27.3 +2.9 32.3 17th 15.0 +3.1 8.4 1st 48.6 28.4 high 171%
Launceston Airport 27.4 34.0 17th 13.4 7.2 1st 21.8
Launceston Airport Comparison 26.5 +3.4 33.1 17th 13.2 +2.9 7.2 1st 23.4 38.7 normal 60%
Low Head 22.4 +1.5 25.9 22nd 16.1 +1.7 11.3 1st 23.2 23.9 normal 97%
Luncheon Hill 24.9 +4.1 32.3 17th 13.0 +2.3 6.8 1st 12.0 57.3 very low 21%
Marrawah 24.0 +3.3 30.9 17th 14.2 +1.9 8.2 7th 7.2 43.5 lowest 17%
Powranna 27.1 +3.1 34.1 17th 13.3 +2.7 4.5 1st 36.1 33.7 normal 107%
Scottsdale 24.9 +1.9 30.1 17th 14.5 +3.5 9.0 1st 77.0 39.8 high 193%
Sheffield School Farm 24.6 +3.5 31.6 17th 13.3 +2.8 8.1 1st 17.6 35.5 low 50%
Smithton Aerodrome 24.3 +2.7 27.7 17th 14.0 +2.6 5.0 1st 4.8 33.6 lowest 14%
Wynyard Airport 23.4 +2.1 26.1 17th 15.0 +3.8 8.9 1st 13.2 49.0 low 27%
East Coast (district 92)
Bicheno 22.1 +0.7 24.6 17th 15.3 +2.4 10.3 7th 41.8 56.7 normal 74%
Eddystone Point 23.2 +2.1 27.0 16th 16.7 +2.6 12.9 8th 45.8 46.2 normal 99%
Fingal 24.0 +1.1 34.6 17th 12.6 +2.7 6.7 7th 44.0 40.1 normal 110%
Friendly Beaches 23.0 0 31.1 17th 15.1 +1.9 11.0 7th 37.6 46.4 normal 81%
Lake Leake 20.0 +1.0 31.2 17th 10.0 +1.8 2.4 1st 20.4 45.7 low 45%
Maria Island 22.1 28.3 18th 15.5 12.2 7th 11.8
Orford 22.0 0 30.5 18th 14.0 +2.0 7.9 1st 17.2 44.7 low 38%
Scamander 21.2 −0.6 24.9 14th 15.8 +3.1 9.9 7th 58.0 34.9 high 166%
St Helens Aerodrome 21.9 27.7 17th 15.5 9.5 7th 70.0
Swan Island 21.8 26.9 17th 16.8 12.7 7th 42.6
Swansea Post Office 22.5 +0.3 30.3 17th 14.7 +2.9 9.2 2nd 23.4 42.3 normal 55%
Midlands (district 93)
Ross 27.0 +2.9 35.8 17th 12.9 +2.4 3.9 1st 13.2 36.4 low 36%
Southeast (district 94)
Bull Bay 22.3 +1.0 34.8 18th 13.7 +1.1 8.4 1st 37.2 41.5 normal 90%
Campania 25.1 36.2 18th 13.4 4.0 1st 30.6
Cape Bruny 21.8 +2.2 36.1 18th 13.9 +1.6 10.3 1st 11.6 61.8 lowest 19%
Cape Bruny Lighthouse 20.8 +2.3 35.0 18th 14.0 +2.4 10.8 1st 16.2 56.5 very low 29%
Dover 22.2 +1.6 36.8 18th 11.3 +0.9 4.9 1st 12.0 51.1 very low 23%
Geeveston 24.1 +2.1 36.6 18th 11.6 +1.9 3.2 1st 23.8 48.9 low 49%
Grove Comparison 24.7 +2.3 35.5 18th 11.2 +1.8 2.4 1st 52.4 46.4 high 113%
Grove 24.7 35.4 16th 10.6 1.4 1st 51.8
Hobart 22.8 +1.1 35.2 18th 14.4 +2.4 7.3 1st 24.4 39.9 normal 61%
Hobart Airport 23.6 +1.3 35.9 18th 14.3 +2.3 6.6 1st 35.8 36.0 normal 99%
Maatsuyker Island Lighthouse 19.5 +2.3 31.8 16th 13.0 +1.9 10.0 1st 10.0 70.1 lowest 14%
Melton Mowbray 25.2 +1.6 34.6 17th 12.2 +2.0 3.4 1st 49.2 34.6 high 142%
Mount Wellington 15.9 +2.2 25.4 17th 7.3 +2.0 0.3 1st 90.2 79.9 high 113%
Tasman Island 18.5 28.0 17th 13.2 8.5 1st 29.8
Tunnack Fire Station 23.0 +1.5 33.2 17th 10.9 +1.9 1.0 1st 23.0 43.5 normal 53%
Derwent Valley (district 95)
Bushy Park 26.9 +3.1 36.2 18th 11.3 +1.3 2.4 1st
Maydena Post Office 25.8 +3.6 35.0 16th 10.3 +1.4 2.0 1st 13.6 63.4 lowest 21%
Moogara 23.2 +3.5 32.5 18th 10.6 +2.0 3.5 1st 20.2 49.0 low 41%
Ouse Fire Station 27.6 36.6 17th 11.4 1.2 1st 28.4
Tarraleah Village 23.4 +3.7 31.9 17th 8.7 +1.7 −0.1 1st 15.8 60.4 very low 26%
Central Plateau (district 96)
Lake St Clair National Park 22.8 +3.7 31.0 17th 7.8 +1.8 0.0 1st 33.8 80.8 low 42%
Liawenee 21.0 29.1 17th 7.5 −1.5 1st 17.2
West Coast (district 97)
Hartz Mountain 21.1 +3.7 32.6 18th 9.1 +1.7 2.4 1st 24.0 59.9 low 40%
Mount Read 19.0 +5.2 27.0 17th 8.6 +2.6 1.9 6th 29.8 166.3 lowest 18%
Scotts Peak Dam 25.1 35.3 16th 11.1 5.2 1st 10.8
Strahan Aerodrome 24.6 +3.4 35.7 18th 11.9 +0.8 4.9 1st 17.6 63.7 low 28%
Strathgordon Village 23.9 +4.4 33.2 18th 11.0 +1.4 4.6 1st 15.8 108.7 lowest 15%
Warra 21.7 32.4 18th 10.2 2.5 1st 14.4
King Island (district 98)
King Island Airport 23.3 +2.4 34.4 18th 14.3 +1.4 4.1 1st 49.6 31.2 high 159%
Flinders Island (district 99)
Flinders Island Airport 24.8 +2.2 31.8 17th 16.1 +2.5 5.4 1st 49.4 38.9 normal 127%
Hogan Island 22.6 29.2 17th 16.9 12.6 1st 46.6
Macquarie Island (district 300)
Macquarie Island 8.4 −0.3 11.9 3rd 5.6 +0.3 3.3 9th 47.4 84.9 very low 56%


Notes

This statement has been prepared based on information available at 11 am on Thursday 1 March 2007. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

Normals are long-term means based on observations from all available years of record, which vary widely from site to site. They are not shown for sites with less than 10 years of record, as they cannot then be calculated reliably.
The median is sometimes more representative than the mean of "normal" rain.

The Rank indicates how rainfall this time compares with the climate record for the site, based on the decile ranking (very low rainfall is in decile 1, low in decile 2 or 3, normal in decile 4 to 7, high in decile 8 or 9 and very high is in decile 10).
The Fraction of normal shows how much rain has fallen this time as a percentage of the long-term mean.

Further information

Ian Barnes-Keoghan or Tom Delfatti
Tasmania and Antarctica Climate Services Centre
Bureau of Meteorology
Phone (03) 6221 2043
Email climate.tas@bom.gov.au