The Atmospheric River misses us again – thankfully – looking to Sunday – Alexa Skill and text Forecast upgrades.

Washington State and Fraser Valley get of it.

This is a good reminder that the Pacific Northwest is a large area encompassing Southern Alaska, BC, Washington, and Oregon and even Northern California when it comes to places where “Atmospheric Rivers” from the Northeast Pacific can be felt.

As you can see by the red and orange areas in the picture below, the heaviest rainfall of the past 48hrs was focused mainly on Washington State with Southern BC and northern Oregon getting the fringes.

The forecast accumulation Wednesday evening’s forecast run looking at precipitation accumulation of the 24hrs between 4AM Wednesday and 4AM Thursday.

This is borne out by Environment Canada’s summary today.

Hope, Cultus Lake, and Chilliwack saw totals for the day over 100mm.

There was heavy rain in Victoria as well last night (67mm), but not like 2021 when there was 120mm at Victoria over three days, and Hope saw 174mm and Chilliwack 154mm in a day. That had added on to what was a very wet few weeks of fall and a slightly more northerly and stronger Atmospheric River which reached up to Cowichan and Nanaimo on Vancouver Island and Howe Sound on the Mainland.

Here are 2021 and 2025 side by side:

2021 Atmospheric River forecast

2025 Atmospheric River forecast

All that said, even with the much weaker and slightly more southerly focused nature of this week’s events, it has still caused flooding in the Fraser Valley as the Nootsak River has overtopped its banks (as it did in 2021) with water now flowing northward into the Sumas basin. The BC River Forecast Centre has the details and is the authority to turn to for water emergency preparedness.

Screenshot from the current map at the BCRFC showing yellow high streamflow advisories covering much of the South Coast and Southern Interior and an area of red flood warnings in the eastern Fraser Valley, Princeton and Similkameen. Link goes to the BCRFC main page, click on “Flood Warnings and Advisories” to see the current map.

Port Alberni only recorded 17.9mm on December 10 and 36mm on December 8. During the 2021 event, even though Port Alberni was left mostly unscathed, we received on the order of 60mm at the peak of that storm.

Looking to the Weekend – more Rain coming

The firehose has lashed northwards and is now sending most of the precipitation into southern Haida Gwaii and the Central Coast as we can see in this morning’s Satellite picture below.

That moisture is expected to slide down Vancouver Island starting Saturday.

moisture reaches Gold River by 4PM Saturday

But that will be relatively weak… a strong push of moisture is expected to gather steam on Sunday night moving from the North Island to the South Island between about 7PM Sunday spreading across the Island and into the Fraser Valley on Monday morning

Sunday 7PM moisture and storm gathers in the Central Coast and begins to move down the Island and South Coast

4AM Monday morning the main bands of moisture are on the Central Island and into the Fraser Valley.

Right now the models have the rain diminishing Monday afternoon, but the Fraser Valley will again be hit hardest as the rain lingers there longest.

We will have to see how this forecast and this weather system evolves but there is a good chance for rainfall warnings to be issued for all of Vancouver Island and the South Coast and likely some wind warnings as well so if you are driving or taking a ferry on Monday morning especially you’ll need to keep an eye out.

Improvements to Alberniweather Forecast text and Alexa Skill

Now that Environment Canada has implemented its new colour based (Yellow, Orange and Red) warning system, I will be updating the software that produces the text forecasts on the front of the page. This will be a relatively slow process as it appears all of the dozens of warnings and watches have changed and the combinations have tripled with the three colours so bear with me if there are some broken links. However, the links will all continue to work and should look something like this in the future:

screenshot of yesterday’s forecast with the new Yellow Warning working

I’ve also updated the Alexa Skill. You must be connected and signed in to the Canada Amazon store (amazon.ca) to see and download the Alberniweather Alexa Skill. It is a “Flash Briefing” skill so you just need to say “Play my Flash Briefing” to activate it and hear the latest conditions from the station. Data is updated every 5 minutes.