During the 6 day period between Saturday July 3 and Thursday July 8, a tropical storm traversed the gulf of Mexico which was named Elsa. The storm twice reached hurricane status being a Category 1 storm on the Saffir Simpson Scale. The storm reached Category 1 just to the south of Haiti and the Dominican Republic and again just to the south of Florida prior to landfall.
Throughout its life span, the storm did not organize itself as a fully fledged tropical cyclone with a distinct eye. The storm passed over landmasses or too close to islands which helped to inhibit its development.
The storm maintained peak wind gusts of between 45 knots (83 km/h) to 65 knots (120 km/h) during its life span.
Since making landfall, the storm has tracked north east across the eastern portion of the United States bringing a period of heavy rain (Forecasts of 50 to 100 mm were being made), thunderstorms and moderate to strong winds to locales in its path.
Despite its strength, this was the first storm to reach hurricane status within the Gulf of Mexico for the 2021 Atlantic storm season.
The attached images are from CIMSS, Worldview and the National Weather Service all showing its appearance throughout its lifespan.
In 2009 on the Australia Severe Weather website, I did a detailed thread titled “Hot Weather at Furnace Creek Death Valley - California June / July 2009”. During this period, an intense heatwave gripped the locality as well as most of the South West region of the United States. It was also a time where minimum overnight minimum temperatures of 40C were recorded being one of only two places in the world where such temperature extremes can occur.
This article only relates to the intense heatwave that occurred at that time and describes the topography and why such intense heatwaves often occur here during June to August each year.
Since this article was prepared, there have been other intense heatwaves at this location and surrounding desert regions.
During June 2021, another intense heatwave has gripped this area and on June 17 2021, the weather station at Furnace Creek Death Valley recorded the hottest verified temperature to date for 2021. A maximum temperature of 53.2C or 127.7F was recorded here. This is just shy of the highest ever June temperature of 53.9C.
A temperature of 50.6C also occurred at Palm Springs east of Los Angeles during the same heatwave.
As described in that thread, much of the heat that occurs here relates to the topography and location. The valley sits between the Armogosa Range to the east and the Panamint Mountains to the west where peaks top 3,368 metres at Telescope Peak. The valley at Badwater Basin sits 86 metres below sea level. During the summer months, heat is trapped over long periods and little escapes during the night. The locality is also within an intense rain shadow so that the air that reaches the valley is extremely dry.
The photos attached to the post are taken in June 2007 following a trip into the valley. The photos clearly show why it becomes so hot here and why maximum temperature records are capable of being broken.
Typically, there is no vegetation available, no water and no relief from the incessant heat.
Weather stations have been placed within the valley to record the extremes of weather and 50C days are common during the summer months. The primary station is at Furnace Creek (Greenland Ranch) just to the north of Badwater Basin. On July 10 1913, it is claimed that it reached 56.7C, here (just to the north where I took the photos) which is the highest maximum temperature recorded. Although while it is accepted by the World Meteorological Organisation, it is still in doubt for a number of reasons, one of which it was recorded by an untrained observer and that the observation may be inaccurate.
A look at the National Weather Service forecasts for this region for the next seven days clearly shows that heat advisory warnings and excessive heat alerts are being issued for much of the desert south west of the USA with forecast highs of up to 118F (48C). A look at the forecast for Furnace Creek for Sunday and Monday 27 and 28 June shows that temperatures are expected to reach 123F (51C) and 124F (51C to 52C) at the Furnace Creek Visitor Centre or immediate environs.
Similar alerts are being issued for places such as Palm Springs and anywhere within the eastern deserts of California and western Arizona.
The current heatwave that is occurring is intense even for such locations and such heat will continue throughout July and August which are the typical summer months.
During August 2019, a significant cold outbreak occurred over Southern Australia that brought low level snow falls to the Blue Mountains including Katoomba and Leura as well as elevated areas of the Central Tablelands. My wife and I documented this event and for the first time ever, I saw snowfall at Leura, Katoomba, Blackheath and Mt Victoria.
The three photos attached are taken from this event. Roads were closed due to icy conditions and snow fell to low levels relatively close to Sydney.
There was also a similar event during the winter of 2020 and now another similar event has just occurred. During the period 8 to 11 June 2021, low level snow fell again across the Blue Mountains, the Central Tablelands and even elevated areas of the Northern Tablelands. In addition, the Snowy Mountains saw heavy snow falls to coincide with the start of the ski season.
The snow images seen in the above photos were again replicated at Leura, Katoomba, Blackheath and Mt Victoria. Generally, snow fell above 850 metres in elevation, roads were closed and icy conditions prevailed.
However this event was remarkable in that Sydney (Observatory Hill) saw its coldest day in decades in which the maximum temperature reached 10.3C following a minimum of just 6.7C (10/6/2021). However what is more remarkable is that this temperature occurred under northern winds. Frigid air was circulating around an intense low pressurecell so that the northerly winds had in fact originated from the south.
It reached a maximum of just 8.9C at Horsley Park and 9.5C at Parramatta.
It is suggested in the media that this could have been the coldest day in 37 years while other media reports suggests that it has not been this cold since 1899.
Some old weather records for Sydney have been reviewed and it is determined that the recent cold day is not the coldest ever recorded for the city as there have been colder days. However, cold days where the maximum temperature fails to reach 10C are rare. Sydney has grown over the years and there are records for Sydney Observatory Hill going back to 1859 and hence the coldest winter days have been:-
Maximum 7.7C on the 19 July 1868.
Maximum 9.1C on the 9 August 1872.
Maximum 9.7C on the 13 June 1899.
Maximum 9.5C on the 8 September 1869.
There is suggestion of a very rare cold day on the 28 June 1836 as reported in the Sydney Morning Herald and around 6 am, the temperature was around 38F (Roughly 3.3C) and it began to snow in the morning with the snow lasting a few hours. It is claimed that the maximum temperature reached 50F (Roughly 9C later that day). This cold day occurred 23 years before weather records began. This event is controversial as there are questions as to whether it was soft hail or actual snow and what instruments were being used to record the temperatures. Either way, the 28 June 1836 was a cold day but whether it was actual snow or soft hail will probably never be known.
The cold day Sydney just experienced was not the coldest on record, but it is rare to see such low temperatures given Sydney’s location and its climate.
There is an account of the 1836 event attached to this post and the fact that snow is suggested in the forecast or weather conditions being experienced for Sydney does make it significant.
The coldest maximum temperature that can be found for Richmond is 9.5C on the 13/7/2011. It reached 8.3C on Thursday which would make it a new maximum low for this weather station and colder than the 11.5C recorded as the maximum day temperature for the 27 June 2007. Records only go back to 1994 at this weather station.
Other low maximum day temperatures for Thursday include:-
Horsley Park 8.9C.
Regional and Rural New South Wales (Including)
Albury Airport - 9.8C.
Armidale 5.6C (At Armidale, it reached 7.6C on the 9/6/21 and 9.7C on the 11/6/21).
Cooma 3.2C with a minimum of 0.0C.
Glenn Innes 5.1C.
Goulburn 6.9C with a minimum of -1.7C.
Orange -0.3C to a maximum of 3C.
Oberon -2C to 5.2C.
The same system also brought some significant rain to certain areas. While Sydney received light to moderate falls some of the rainfall that occurred elsewhere was remarkable given location.
An area to the south of the Great Dividing Range but east of Melbourne received some heavy rainfall which resulted in flooding. Flooding was observed around Taralgon as well. Some of the heaviest falls for the 24 hours to the 10 June 2021 include:-
Thompson Yarra Divide - 241 mm.
Licola - 170 mm.
Noojee - 154 mm.
Reeves Knob - 144 mm.
The hilly areas of outer Melbourne’s east received between 50 and 100 mm. In addition to the rain, power was lost and trees were brought down due to wind and a clean up is currently underway.
New South Wales
Perisha Valley - 62 mm (Mostly as snow).
Thredbo - 50 mm (Mostly as snow).
A rain event across parts of the Central West of New South Wales saw good totals of up to 42 mm falling including 42 mm at Dubbo, 40 mm at Barina, 38 mm at Neura and 36 mm at Coonabarabran.
There were instances of wind damage and trees being felled especially across snow affected areas and across southern Victoria. However, the strongest wind gusts occurred at Mt William (The Grampians) where a single gust of 115 km/h occurred. Further, the lighthouse at Wilsons Promontory recorded one windgust of 111 km/h at 2.30 am on the 10/6/2021 and the Puckapunyal West (Defense) weather station recorded a single gust to 111 km/h at 3 am on the same day.
At Mt Buller, peak winds gusts reached between 104 to 107 km/h for the 10/6/2021.
As such, this was a dynamic weather system that has created a wind range of weather that has disrupted large swathes of South East Australia. During Friday, conditions moderated dramatically allowing for a clean up to occur including a gradual warming of daytime temperatures.