Rumbles rock the country from sky and earth

What a wild 24 hours of weather!

Let's start off with 8.17am yesterday when a magnitude 5 earthquake shook WA's Goldfields, 10km southwest of Kargoolie. According to Geoscience Australia, we experience earthquakes of this magnitude in our country around once a year, but because they often occur in unpopulated regions they largely go unnoticed. That certainly wasn't the case in Kargoolie yesterday when food toppled off supermarkets shelves, and roofs turned to rubble in just ten terrifying seconds. The quake also forced the closure of Australia's larget gold mine, the Super Pit.

90% of all earthquakes occur on tectonic plate boundaries due to the movement of plates against eachother, so considering that Australia is situated smack bang in the middle of the Indo- Australia plate, this sort of earthquake comes as a shock. But fault lines within tectonic plates often cause such tremors, infact Geoscience Australia has measured around 20 small earthquakes in Australia in just the last month alone!

From rumbles in the earth to rumbles in the sky, severe storms barrelled across South Australia and Victoria yesterday bringing flash flooding thanks to large rain totals. Andamooka was hit by its second major storm in just two weeks with 38mm, while south-eastern suburbs in Melbourne such as Lyndhurst received 47mm. Today scattered showers and storms are possible in SA northeast of Coober Pedy to Port Augusta to Renmark, as well as central and eastern parts of Victoria. Some storms could be severe but are unlikely to be as volatile as yesterday.

Fire and Ice: Icelandic volcano closes European airports

The second Icelandic volcanic eruption in a month has catapulted tonnes off ash into the atmosphere. High altitude westerly winds have spread the ash plume as far as 1000km from the volcano itself closing major airports across Europe- and leaving thousands of travellers stranded.

The atmosphere is broken up into various levels depending on their temperature profiles. The troposphere is the first 10km of the atmosphere and this is where all our weather happens. The next level is the stratosphere, a stable layer with very little weather. The boundary between these two layers is known as the tropopause and large aircraft usually fly just above this boundary since the absence of "weather" provides calm conditions and little turbulence.

When a volcano erupts, it often spews up a huge amount of ash with such great force that tiny particles reach as far as the stratosphere. Even if the ash isn't visible, this poses a problem for aircraft as it can enter the engines and cause damage, electrical failures and faulty instrument readings. This is the primary reason why many airports across Europe have closed today.

Volcanic eruptions can also have a significant impact on the short-term climate. A large amount of ash in the atmosphere can effectively act as a barrier against solar radiation leading to a period of cooling. The most recent example of this is the 1991 eruption of Mount Pinatubo in the Phillipines- it's ash cloud dropped the average temperature by 0.4-0.5 degrees.

Autumn sets in across much of the country

If you've dusted off the uggies this week, then you're probably not alone with most of the country experiencing well below average temperatures and their coldest mornings in months this week. A strong cold front crossed the southeastern states over the weekend leaving cold Antarctic air in its wake- and shivering Aussies! This morning, Cooma Airport in NSW got down to a chilly -5.7 degrees while Canberra experienced a frosty start getting down to just below 1 degree. The cold, southerly air reached as far north as southern inland QLD with parts of the Darling Downs and Maranoa and Warrego districts waking up to single digits.

Southwest WA have also had an icy taste of Autumn but it has been the opposite of the crisp, clear skies across the southeastern states. A low pressure system spiralling off the southwest coast has been churning in cold air, heavy showers and damaging winds, keeping SES crews very busy overnight. A severe weather warning for locally damaging winds and abnormally high tides still stands for the Southwest and adjacent parts of the Lower West districts, including Mandurah, Bunbury and Busselton. From yesterday up until midday local time, Busselton had picked up almost 50mm of rain. Conditions will begin to ease this afternoon.

Record rain floods inland South Australia

The heaviest rain in a generation has left many towns across inland South Australia flooded. Roxby Downs averages 12mm of rain for the whole month of April, but this morning, 86mm pelted the town in a matter of hours, including 13mm in 10 minutes! This was its heaviest rain in 13 years. Other massive 24 hour rain totals to 9am this morning incude:

- Andamooka 85mm – heaviest in 21 years, April record (site started 1965)
- Leigh Creek 67mm to 9am and still pouring!
- Woomera 34mm - heaviest rain in 16 months
- Tarcoola 27mm - heaviest rain in 5 months

The deluge is gradually clearing from South Australia as the system moves east, with rain now falling over western NSW and Victoria.

Rain, storms and flash flooding are also affecting Alice Springs , sending the normally dry Todd river flowing once again. With heavier rain expected this weekend, be prepared for a "dead track" for the Alice Springs Cup.

Salt turns into inland sea!

I just got back from an amazing adventure through the Australian outback and was lucky enough to see the floodwaters feeding into Lake Eyre at the moment. The heavy rain in recent months that put southwest QLD underwater also left the Georgina and Diamantina rivers swelling and those waters have been flowing into the Warburton river. This river feeds into Lake Eyre and as you can see in the photos that I took from the air, the normally dry and salty lake has taken on a striking shade of blue! This rare pulse of water has enticed hundreds of pelicans and aquatic life to the region.

But there's more water on the way- and it's not just the floodwaters that are still continuing to flow into the salty lake. A northwest cloudband across central Australia right now is expected to deliver widespread falls of 25mm or more across SA's pastoral districts over the next 48 hours. So as well as capitalising on inflows from QLD's floods, Lake Eyre is set to receive around 25-50mm of its own rain. This will provide bird and aquatic life with even more incentive to trek all the way out to the driest part of our country, not to mention travellers eager to see outback come to life during this uncommon flooding and rain event.

Anna Creek Station, which is located to the western side of Lake Eyre, has also benefited from recent rains. The drought-stricken cattle station now boasts full dams and veins of thick green vegetation where rivers and and streams have been running. Half the size of Tasmania, Anna Creek Station is the largest cattle station in the world.

And it doesn't stop there- rain and storms across Alice Springs may lead to localised flooding, sending the Todd river flowing once again.