While heavy rain is expected to dampen Canada’s 150th birthday celebrations Saturday on Parliament Hill, high-level security experts in both police and intelligence agencies are hoping the only explosions heard will be emanating from the thunder clouds overhead. A national security memo, obtained by CTV News, has the ISIS terror group again “explicitly” naming Canada as a target, with its text warning Muslims to avoid markets and large gatherings as it threatens to use “explosives, vehicles and beheadings to kill crusaders.” This threat is a recent one. It was intercepted after the Manchester bombing in England on May 22 when a homegrown Muslim extremist in a shrapnel-laden suicide vest killed himself and 22 young people attending an Ariana Grande concert. Despite this latest warning, however,…