Tue. Mar 26th, 2019

Gauging the rain to come

  • Vancouver Island Inland Sections Forecast - No watches or warnings in effect.

    Forecast Issued 4:00 PM PDT Tuesday 26 March 2019 - Tuesday night: Mainly cloudy. 30 percent chance of showers early this evening with risk of a thunderstorm. Fog patches developing late this evening. Low plus 2. Wednesday: Clearing late in the morning. Fog patches dissipating in the morning. High 16. UV index 3 or moderate. Wednesday night: A few clouds. Fog patches developing overnight. Low plus 2. Thursday: A mix of sun and cloud. High 18. Thursday night: Clear. Low plus 2. Friday: Sunny. High 18. Friday night: Clear. Low plus 3. Saturday: Sunny. High 18. Saturday night: Cloudy periods. Low plus 5. Sunday: Cloudy. High 13. Sunday night: Cloudy with 60 percent chance of showers. Low 6. Monday: Cloudy with 60 percent chance of showers. High 12.

  • Current Conditions
    11.1° C
    -0.3 ° C/hr
    101.75 kPa
    SSW 12.9 km/h
    gusting 20.9 km/h
    73 %
    Rain Rate
    0.0 mm/hr
    Wind Chill
    11.1° C
    Heat Index
    11.1° C
    6.4° C
    350 W/m2
    Last Updated: 17:05:00 PST
    Click to Refresh or See All Conditions
  • Day Almanac
    Day's Rain
    3.8 mm
    Day ET
    0.0 mm mm
    Rain Storm
    NotAvailable mm
    Civil Rise
    Moon Phase
    Waning gibbous (62% full)
    Civil Set
    Day Length
    Day High
    11.6° C @ 15:57 Tdy.
    Day Low
    5.9° C @ 07:59 Tdy.
    Day High Rain Rate
    8.4mm/hr @ 05:35 Tdy.
    Day High Barometer
    101.79 kPa @ 13:29 Tdy.
    Day Low Barometer
    101.29 kPa @ 00:00 Tdy.
    Day Low Windchill
    3.9° C @ 00:16 Tdy.
    Day High Heat Index
    11.6° C @ 15:57 Tdy.
    Day High Wind Gust
    S 14.5km/h @ 12:55 Tdy.
    Day High Solar Radiation
    1046W/m2 @ 13:05 Tdy.
    Day High UV Index
    3.3 @ 13:04 Tdy.

There is no doubt it will rain starting Thursday or Friday. In fact, as I type this there is a light mist falling in Qualicum.

First, it’s worth remembering how much rain we need, which is a lot even for us on the West Coast.

Not since 1896 (in Beaver Creek) and 1929 (at City Hall) has there been a summer and fall this dry in Port Alberni. However, already this October has been more extreme than 1896. If you look at the daily data, rain fell on and off throughout October 1896. In 2012 we have yet to register rain in October. (October 1929 was a more typical month with over 180mm falling throughout)

The totals are most compelling though so again, July-October, 1896 got 159mm, 1929 got 214.9mm, and 2012 has 36.2mm so far. So we need over 122.8mm to dodge the 1896 record. (Apologies I’ve said 140mm in the past, bad in-head math on my part)

So will we get it and avoid the record? It is still hard to say. Initially this weekend’s rain looked intense. But it has flipped and flopped. Here is the latest GFS prediction.

It shows a very merger start with a strong punch on Saturday and Sunday night totalling over 144mm!

That would take care of the record.

However, the GFS often overestimates. So what does the Canadian model say? Here are the accumulations from Friday through Monday with graphics available here.
10mm on Friday.

30mm on Saturday

35mm on Sunday

50mm on Monday

Total: 125mm

That would also put us over the 1896 amount and avoid setting a new record.

So now we wait and see if the forecast holds. There is rain in the long range forecast too… But we will address that maybe on the weekend. Rain amounts are often the most difficult to predict, but whatever we get, it will be a blessing for local rivers and the people and animals that depend on them.