Weekend storm heralds long-awaited pattern change
Wednesday, February 18, 2015
The current sunny weather will last through tomorrow, with warming temperatures noted. A storm currently rounding the west coast ridge near the coast of British Columbia will mix with some cold air from the Hudson Bay vortex and turn potent, first bringing clouds to the area early Friday followed by showers later in the day.
Temperatures should drop quickly Friday night accompanied by periods of moderate to heavy snows as the storm enters the Great Basin. Pieces of energy ejected from the storm along the frontal boundary will keep strong upward motion over the area through the day Saturday, continuing the moderate to heavy snows in seasonably cold temperatures.
The snowfall forecast will likely change as the event nears and models gain a better handle the storm’s evolution, but I expect significant snowfall to be reported through the weekend. If snow starts by Friday afternoon, I would expect 4-8” to be reported Saturday morning with probably another 3-6” during the day Saturday.
By Saturday night, the storm system becomes sheared as a piece of the storm moves westward over northern California, creating a broad area of lift extending across the Great Basin and into the Colorado Rockies. It looks like snows will continue Saturday night and through Sunday as some of the wave that initially contributed to the cold air on Saturday moves towards our area from the north and interacts with the weakening storm over northern California. Adding the 3-6” during the day Saturday with a forecast of 3-6” of snow overnight yields a 6-12” by report Sunday morning. And another 3-6” during the day Sunday which will be reported Monday morning yielding storm totals of 1 to 2 feet.
Snows should end by Sunday night or early Monday as we are caught between the California storm and the jet stream to our north and east. Though Monday will start cold, seasonable temperatures should return as the workweek progresses before another somewhat similar storm threatens our region by the end of the workweek.
The good news for the medium to long term is that these storms look to end the dominance of the west coast ridge for a while, allowing periods of stormy weather to cross over the area. It appears March might be coming in like a lion!