13 Jul 2014 - A 1024 mb Pacific high continues as the dominant feature over the BC coast, however the ridge will weaken slightly as a 1015 mb trough moves over the south coast. The high will restrengthen on Monday. Conditions will continue clear and exceptionally warm in most areas. Daytime temperatures will continue to be well above seasonal normals with high humidity and extreme heat in the Alberni Valley across to the Comox Valley. (Port Alberni broke its previous high temp record yesterday and it is expected to break that record today. The Fraser Valley will come close to matching its previous high temp record). Overnight should bring some cooling to Vancouver Island and the lower mainland as a late day onshore flow occurs and a layer of marine air moves in as far as the Fraser Valley. A marine atmoshpere layer boundary (MALB) extends from the central coast and down the west coast Vancouver Island due to cold sea surface temperatures and high dew points. This condition has created overnight fog banks in the northern inside straits as far as Sayward, along the west coast Vancouver Island and into Juan de Fuca Strait as far as Whidbey Island. The stratus event on west coast Vancouver Island is significant enough to bring drizzle this morning. This entire scenario will repeat overnight with fog and low stratus clouds along the MALB tomorrow morning. As the Pacific high restrengthens on Monday a late day onshore breeze will become strong to Gale Force. Longer range: Temperatures will moderate slightly after today, although Tuesday could see a repeat of the weekend with Wednesday becoming cooler. I will not attempt to forecast beyond Wednesday given the data, although a rough estimate suggests a return to seasonal normal temperatures with continued clear conditions. - West coast Vancouver Island winds moderate NW becoming strong this afternoon and to NW Gale Force to 35 knots (65 kmh) north of Tofino. From Tofino southward extensive fog and possible drizzle, dissipating this afternoon, reforming overnight. Afternoon and evening gales will become a daily regime through to Wednesday. - Queen Charlotte Strait winds light becoming moderate NW this afternoon and easing to light overnight. Fog banks, with possible drizzle, extends from Calvert Island to Johnstone Strait should dissipate by midday. - Johnstone Strait winds moderate NW rising to NW Gale Force to 35 knots (65 kmh) this evening in the gaps, easing to strong tomorrow morning and rising to Gale Force tomorrow night. Fog banks extending from Queen Charlotte Strait to Sayward should dissipate this morning. - Georgia Strait winds light to moderate NW becoming strong this evening, easing tomorrow morning and becoming strong NW tomorrow afternoon. - Juan de Fuca Strait, Victoria waterfront winds moderate W rising to W Gale Force to 35 knots (65 kmh) late this afternoon, easing overnight. Fog extending from the west entrance to Whidbey island should dissipate this morning. North of Race Rocks, Constance Bank conditions remain clear.
Posted on: Sun, 13 Jul 2014 14:54:51 +0000