West Coast storm update

Computer models have diverged on the track of the second storm (what was once Typhoon Songda) coming into the west coast later Saturday into Saturday night. Before that, we have storm #1 which will bring significant precipitation and locally strong winds later Thursday and Thursday night,

The satellite image of the North Pacific below clearly shows the distinct corridor of clouds/moisture that is directed toward the Pacific Northwest and BC.

Storm #1

Current trends support a 975-980 mb low pressure area tracking into Vancouver Island Thursday evening with the heaviest rainfall coming Thursday afternoon and Thursday night across southern BC. Snow levels will be fairly high across the Coastal Range with this storm, but well to the north in the colder air, there will be a band of steady snow stretching into northern Alberta Thursday night into Friday.

As low pressure passes across central Alberta on Friday, there will be a narrow zone of strong, west to southwest downslope winds across extreme southern Alberta with gusts in excess of 80 km/h.

Storm#2

The latest ECMWF (European model) has trended much farther south with the track of storm #2 (formally Typhoon Songda), which would keep the real strong winds down across coastal Oregon and southern Washington. On the other hand, the latest GFS and Canadian models still have this storm coming up into Vancouver Island with a central pressure near 953 mb later Saturday, which would bring powerful winds to southern Vancouver Island and into portions of the lower mainland and mountains. Still a little too early to tell which track will be correct. Regardless, this second storm will be loaded with tropical moisture and rainfall totals through Sunday night will be impressive.

ECMWF model total precipitation from today through Sunday night (mm).

GFS model total precipitation forecast from today through Sunday night (mm).

ECMWF total snowfall forecast in inches through Sunday night. Snow levels will be about 1,000 feet lower on average for storm #2 compared to storm #1.

Elsewhere.......

1. Cold front will come through eastern Canada later tonight into Thursday with some showers then slightly cooler air.

2. A second cold front with modified Pacific air will push through eastern Canada Sunday into early Monday with another batch of showers.

3. The East will experience a warming trend next week as the jet stream lifts northward in response to all the energy going into the West.

Projected five-day temperature anomalies (degrees Celsius) between now and Sunday.

Projected five-day temperature anomalies for next week. Note the warmer anomalies concentrated in the East. Going to feel more like September!

4. Signals indicate a turn to more seasonable (cool) conditions in the East after Oct. 20 as a high pressure ridge begins to build over the Rockies.

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