Environment Canada has issued a series of heat warnings for parts of B.C., with the first week of September set to bring temperatures as high as the mid-30s in some places. According to the weather agency, a ridge of high pressure anchored over the province will bring temperatures of up to 35 C in the Fraser Canyon region, from as far north as Lillooet to as south as Lytton. Nighttime lows are expected to dip to 18 C. Along the north and central coasts and in North and South Thompson, temperatures are forecast to reach the mid 30s, with overnight lows expected to linger around the 13 C mark. The spike in temperatures is expected to last for three days, before a cooling period sets in as the weekend nears. Those in the affected areas are advised to watch out for early signs of heat illness, which typically include feeling unwell, fatigue, thirst and headaches. Those at greater risk include seniors, those who live alone, and people with pre-existing health conditions, the weather agency said.