Rain is forecast for Perth this weekend, but even if it arrives, will it be enough to prevent the driest four-month spell on record?

Here's what we can tell you about Perth's recent rainfall: we can't say much, and that's because there is not much to say.

If a picture tells a thousand words, then take a look at the graph below. It shows the Perth rainfall over the last 12 months.

The period from the start of December 2023 is of interest here. See how there has been almost no rainfall since the start of December?

It's of course not unusual for Perth with its "Mediterranean climate" to have dry summers, but the 2022/23 summer was the third-driest on record, with just 1.4 mm across three months.

• While a typical Perth March is also dry, a slight uptick in rainfall totals usually occurs, with a monthly average of nearly 20 mm.
• But March 2023 has seen just two rain days to date, for a meagre total of 1.6 mm.
• Add that to the summer total of 1.4 mm, and that's just 3.0mm since the start of December up to 9 am on Friday, March 24.

That means we're now only a week out from an unwanted record.

• Perth's lowest December-to-March total on record is 6.7 mm from 1949/50.
• Indeed that was the city's driest four-month period in any four consecutive full months.

The question is whether enough rain falls in the coming week to top that 6.7 mm figure? As mentioned, that depends on how much rain falls this weekend, as the following week should stay mostly dry.

As you can see on our Perth forecast above, there's the potential for 10-15 mm this coming weekend. Bear in mind that this is our upper estimate.

As any local knows, Perth's heaviest rain tends to come from the west and southwest, and this weekend's potential rain will come from the east. A trough over southern WA is likely to generate heavier falls in inland areas, but how much will make it to the coast?

Fingers crossed, Perth gets a welcome drop or two, and perhaps even a decent soaking. But it's also possible that the WA capital will be staring at its driest four-month period on record by Monday. We'll keep you posted.