Temperatures to rise across heat-weary NSW
Ben Domensino,
Wednesday February 8, 2017 - 12:03 AEDT
Oppressive heatwave conditions gripping New South Wales this month will intensify across the state at the end of this week.
Much of Eastern Australia has been feeling the effects of a large and stagnant pool of hot air since late January.
The lengthy string of hot days and nights has been caused partially by persistent high pressure systems over the Tasman Sea. These highs have prevented strong southerly changes from penetrating into New South Wales.
Another feature to blame for the recent heat has been the quiet cyclone season to date. Cloud and rain produced in the tropics by the monsoon trough and tropical cyclones at this time of year moves south and helps to erode hot air masses over Australia's mid-latitudes.
This season, there has only been one tropical cyclone in Australian waters and it was relatively weak. According to the Bureau of Meteorology, we are currently experiencing the longest period on record without any severe tropical cyclones forming in the Southern Hemisphere.
So far this month, all central and northern regions in New South Wales have experienced hotter-than-usual conditions during both the days and nights. Some locations in the state's north have exceeded 40 degrees for the last 11 days straight.
Walgett's run of days over 40 degrees reached 10 on Tuesday, bringing their tally for summer to 26. The town could increase this number to 31 days by the start of next week, which would be the highest number of days over 40 in summer for 65 years. The record is 39 days from 1951/52.
Bourke is expected to reach 16 days straight above 40 degrees on Sunday, making it their longest stretch this hot since 1939. The current record is 22 days in a row from 1896.
Temperatures are set to climb during the next few days as northwesterly winds develop ahead of a pair of cold fronts, which will cross Tasmania and Victoria on Thursday and the weekend.
The mercury will reach the low to mid forties for most areas west of the ranges on Friday and could get to 47 degrees in the Upper Western District on Sunday, which is 12 above average. Many coastal areas will also reach into the forties on the weekend as heatwave conditions grip the entire state once again.
Sydney has already endured a record-matching nine days over 35 degrees and have 12 on the board by Sunday. This new record would be an impressive feat considering the city's historical record spans 158 years.
Western Sydney could break single and multi-day heat records at the end of this week.
Richmond is forecast to reach 43 degrees on Friday and Saturday and 41 on Sunday. This would bring their tally of days above 43 to seven this season, smashing the old record of two days from 1958, 1979 and 2003.
There is a chance that Sunday could be hotter than the forecasts, giving Richmond and Penrith a chance to have three days over 42 degrees for the first time in observed history. Data at these sites goes back to 1953 and 1995 respectively.
Single-day February heat records to watch on the weekend will be 43.7 degrees at Richmond (from 1977), 43.3 degrees in Bankstown (from 1977), 42.6 degrees at Sydney Airport (from 1980) and 42.1 degrees in the city (from 1926).
Looking ahead, one of the strongest southerly changes since mid-January will drop temperatures across New South Wales early next week, allowing places like Bourke to have their first day below 40 degrees in more than two weeks. Sydney will drop back to the mid-twenties by Monday.
- Weatherzone
© Weatherzone
2017