Sun on hot day
Hot weather. (File photo courtesy National Weather Service)

An intense and prolonged July heat wave kept the San Diego area in its sweltering grip Wednesday, generating more potentially health- endangering temperatures in some areas with little relief in the extended forecast.

The oppressively hot conditions, which are due to linger through the weekend, include thermometer readings in the mid-90s to just over 100 degrees in the mountains and up to 119 in desert communities. The National Weather Service issued an extreme-heat warning for those locales until at least 8 p.m. Monday.

In the arid, sun-blasted eastern reaches of the county, even the nighttime lows are expected to be quite warm — remaining in the upper 80s to mid-90s on Thursday and Friday, meteorologists advised.

For coastal and inland-valley areas, where temperatures are expected to climb as high as the lower 90s and 105 respectively, a less urgent NWS heat advisory was scheduled to remain in effect over the same period.

Authorities advise people in the hottest spots to prevent heat-related ill health effects by drinking plenty of non-alcoholic fluids, staying out of the sun during the warmest times of the day, taking shelter in air- conditioned spaces if possible and checking up on at-risk friends, relatives and neighbors.

People are also reminded to never leave children or pets in a parked vehicle for even a minute, as inside temperatures can rapidly reach deadly levels.

Monday and Tuesday should cool a few degrees each, but more temperature-raising high pressure could return near the end of next week, forecasters advised.