Australian Weather Calendar: April 2019

April photograph by Jenny Feast Photography

Keeping an eye on the sky

It's no coincidence that Jenny Feast happened to be in the right place at the right time to capture this dramatic lightning strike over Middleton Beach in Albany, Western Australia. A trained weather observer who has worked at the Bureau of Meteorology since 2009, Jenny's role often requires her to keep an eye on the sky. A self-confessed 'weather nerd', Jenny's love for weather photography (and surfing!) ensures that even at home she's constantly checking the Bureau's synoptic charts and radar imagery. As part of her work she's first to know what the weather is likely to bring, thanks to the release of weather balloons that track wind speed and direction, temperature, humidity and air pressure. Jenny said she knew there was something special brewing the night she caught this striking shot. 'There was a cracking rumble after the lightning, and the concrete platform we were standing on shook,' she recalls. Jenny's different postings at the Bureau have meant she's been able to photograph diverse weather all over the country and in remote locations including Willis Island, Cocos Islands, and Antarctica, but it's the scenic coastline and tight-knit community of Albany that has captured her heart.

The science

Snaking through stormy skies, lightning like that in this photo is one of nature’s most spectacular displays—but it can also be spectacularly dangerous. The high-voltage show is caused by an electrical discharge that occurs within a thunderstorm cloud, between clouds, from clouds to the ground and even from the cloud top into the atmosphere. In the cloud, there are millions of tiny ice crystals and super-cooled water droplets rubbing against each other as they move up and down. This causes a positive charge to develop at the top of the cloud and a negative charge at the bottom. When they discharge, a powerful electric current races from the cloud to the ground and that's when we see lightning.