Remnants of Tropical Cyclone "Joyce" brought record-breaking rain to parts of SW Western Australia on Monday, January 15 and Tuesday, January 16, 2018. The storm produced wind gusts up to 90 km/h (56 mph) and dumped more than 4 months' worth of rain in less than 24 hours on parts of the region, causing floods, power outages and traffic problems. Some areas saw their wettest day ever.
January is typically one of the driest months in this part of the world, but Joyce's remnants brought widespread rain, in places 4 - 10 times more than they see during the entire month of January.
Perth, capital and the largest city of the state, received 96.2 mm (3.78 inches) of rain within 24 hours ending 09:00 local time Tuesday, January 16, on top of nearly 8 mm (0.31 inches) before 09:00 Monday, making it the city's wettest January day in 18 years and the second wettest day in history. Since Perth sees only about 9.7 mm (0.38 inches) of rain during January, the amount it received now is nearly 10 times it usually sees in January. The last time the city saw this much rain in January was on January 22, 2000, when BOM recorded 104 mm (4.09 inches).
While Perth made all the news because it's the most populated area in the region, some other places saw even more rain. During the same period, Jandakot saw 118 mm (4.64 inches), Bickley and Swanbourne recorded 139 mm (5.47 inches), Rottnest measured 142 mm (5.59 inches), Huntly 144 mm (5.66 inches), Dwellingup Forestry 147 mm (5.78 inches), Saddleback Road Bridge 149 mm (5.86 inches) and Marradong 163 mm (6.41 inches). Rottnest, Bickley and Swanbourne all received their biggest downpours ever recorded in 24 hours.
More than 100 mm (3.93 inches) of rain was recorded at more than 30 stations and all of those with documented records had them broken while others also recorded remarkable rainfall and totals that likely obliterated any unofficial records, Higgins Storm Chasing reports.
"With further lingering showers and rain areas across the next 24 hours through southwestern Western Australia and the assumption that at least 1 more system will move through the region over the next 3 weeks, it looks like a fair chunk of the SW pocket of Western Australia should see its wettest January ever," they added.
24-hour rainfalls to 09:00 AWST, January 16, 2018 - Western Australia. Credit: BOM
Here are some of the significant rainfall totals Higgins Storm Chasing archived on their page (24hr totals ending 09:00 AWST, January 16):
• Marradong 163 mm / 6.41 inches
• Saddleback Road Bridge 149 mm / 5.86 inches
• Dwellingup Forestry 147 mm / 5.78 inches (2nd wettest January day ever)
• Huntly 144 mm / 5.66 inches
• Rottnest Island 142 mm / 5.59 inches (almost triple the previous daily record)
• Bickley 139 mm / 5.47 inches (more than the previous monthly record, 2.5x the daily record)
• Karragullen North 139 mm / 5.47 inches
• Roleystone 139 mm / 5.47 inches
• Swanbourne 139 mm / 5.47 inches (almost 2x the previous daily record, and 1 mm / 0.03 inches shy of the monthly record)
• Oneil Road 138 mm / 5.43 inches
• Mount Solus 134 mm / 5.27 inches
• Gordon 132 mm / 5.19 inches
• Karnet 131 mm / 5.15 inches
• Mount Curtis 129 mm / 5.07 inches
• Jandakot AP 119 mm / 4.68 inches (smashed the previous daily January record)
The best view of ex-cyclone Joyce and its rain band is from outer space. Plenty of totals in the 50-100mm range through Central West and Gascoyne; now it's the Metro's turn. 20-40mm so far through the city, with significant rainfall still to come tonight #moist #BigWet pic.twitter.com/YF7Yj3KKQR— Bureau of Meteorology, Western Australia (@BOM_WA) January 15, 2018
Today the Gascoyne River at Jimba (near Gascoyne Junction) jumped from zero flow to 3 metres high and 600 cumecs discharge in 2 hours. That's enough flow to fill an Olympic sized pool in 4 seconds! See the latest warnings and info here - https://t.co/NikaX4QRKr pic.twitter.com/2ChU8KpYr1— Bureau of Meteorology, Western Australia (@BOM_WA) January 15, 2018
The rain caused flooding in parts of the region and left more than 1 300 homes without power after strong winds downed power lines. Some of the flights arriving at Perth Airport were delayed as pilots were forced to circle around the airport after numerous landing attempts due to strong winds.
The Department of Fire and Emergency Services said they received more than 330 calls for help since 09:00 local time Monday, mostly along the Perth coast, while RAC said they received more than 670 insurance claims.
Featured image: Ex-Cyclone Joyce affecting Perth, Western Australia on January 15, 2018. Credit: 9News Perth