Whilst rainfall in eastern Australia is generally welcome at the moment, together with low cloud it's been frustrating for those travelling.

On Friday and Saturday, the rain has been flooding roads, cloud has been lowering to the ground, and combined rain and cloud have been reducing visibility. This has not just slowed down travel, it's caused huge delays.

Flights have been significantly delayed, particularly at Sydney Airport where low cloud has been stubbornly persistent, consistently lower than 200 metres for much of Saturday morning. Many flights have had to be diverted but even this has been problematic given how the widespread nature of the low cloud. The thick cloud has lowered to less than 300 metres at times at Brisbane Airport, and below 200 metres almost all day at Melbourne Airport. Flights typically require cloud to stay above 500 metres to run to schedule. Thankfully, one of the other major airports in the country's east, Canberra, has been operating under easier conditions, with cloud staying above that height.

Those using the roads have had to exercise extreme caution, particularly in Sydney's south where more than 100 millimetres of rain fell, more than half of that in just a few hours on Friday evening. Some roads rapidly became rivers, leaving some drivers requiring help from emergency services.

Looking ahead, rain, low cloud and low visibility will continue to hamper the Brisbane, Sydney and Melbourne airports. Heavy downpours, cloud lowering below 500 metres and visibility dropping to just a few hundred metres can be expected at times until Monday morning in Brisbane, and until Sunday morning in Sydney and Melbourne. Canberra and many other airports and transport routes also expect similar conditions until at least Sunday morning

The offending weather system, a slow-moving low pressure trough will weaken on Sunday night and Monday, allowing conditions to improve. However, the still air makes thick fog a chance on Monday morning.

Image: Fog and low cloud prompting nature's fliers to plan their diversion before take-off.