Significant rain has fallen in Perth for the first time in many months, with 31.8 mm falling by 5:30 am (AWST) in the city and similar totals in most suburbs.

For locals, the heavy rain that mostly fell in the pre-dawn hours of Friday March 31 will be extremely welcome.

• Last Friday (March 24), Weatherzone ran a story noting that Perth looked likely to set a new record for the city's driest four-month period in any four consecutive full months
• Just 3 mm had fallen from December 1 through to March 24, which was less than the record four-month dry spell of 6.7 mm in December-to-March 1949/50

But the last day of March has changed all that, and how.

• It's currently Perth's wettest day since April 11 2022, and Perth Airport (34.0 mm by 5:30 am) is having its wettest day since July, 2021
• Perth's last day with a double-digit rainfall total was November 18, 2022, with 23.2 mm

Perth's heaviest rainfall normally comes from the west or southwest, but the overnight rain blew in from the north in a moist flow fuelled by a low pressure system and associated trough.

You can see the green rain blob over Perth clearly on the three-hour radar loop from 1 am to 4 am Friday below.

Perth has been teased a bit of late, with green blobs near the city but missing it. Last night, bullseye!

You can also see Severe Tropical Cyclone Herman on the loop. It was upgraded to a Category 4 cyclone early on Friday morning (from Cat 2 on Thursday) however the BoM advises it poses no threat to the WA coastline at this stage, and it is expected to lose strength throughout Friday.

Meanwhile showers should stick around in Perth for a few hours on Friday morning before things start to clear.

A fine week is ahead, so the gardens of Perth can be grateful they got a good soaking with no more wet weather on the short-term horizon, while footy fans will be glad of clear skies for Sunday's Western Derby at Optus Stadium