A frontal wave over central BC this morning will push southeastward today to lie over southern Alberta this evening. The supply of moisture from the front is forecast to be cut off throughout the day with precip rate diminishing. The trailing cold front and upper trough will move across the province today and the upper flow will turn northwesterly. As a result freezing level will lower across the province through tonight.
Meanwhile an Arctic front over northeastern BC will move south and eastward following the wave to move over the Rockies and Alberta tonight.
In behind the upper trough a weak upper ridge will keep most of BC dry on Saturday. Another Pacific front is forecast to approach the North Coast and White Pass regions during the day Saturday. The Arctic front will linger around northeast BC and the Rockies over the weekend. The Pacific front is expected to push into the interior and southwestern BC on Sunday spreading generally light precip. Another Pacific system will spread more precip to all regions on Monday.
Confidence is high in the short term as the models agree on the track of frontal wave and the Pacific system. However near the north edge of the precip in the Northwest sections freezing levels had been falling faster than the model suggested since last night. It is possible that this trend will continue this morning further south in heavier precip.
Confidence is moderate in the longer term as all models generally agree on the systems and precip pattern through Monday. There are some differences on the southern extent of the precip on Sunday and Monday.