Dry, hot and windy conditions in San Diego County this week add up to increased fire danger, authorities warned Monday.

National Weather Service

High-pressure systems will strengthen over the Great Basin and along the West Coast through Thursday, bringing much warmer daytime temperatures, along with low humidity levels and strong air currents out of the east and northeast, according to the National Weather Service.

The most extreme conditions were expected to occur Tuesday and Wednesday, the NWS reported.

A “Red Flag” warning — denoting increased wildfire danger — was slated to be in effect for inland valley and mountain areas until 8 p.m. Wednesday. Sustained northeast to east winds of 20-30 mph and gusts to 75 mph in some locales are likely over the period, mainly along coastal slopes and below passes and canyons. The humidity is expected to dip to as low as 5 percent.

Triple-digit temperatures were likely by Wednesday, according to forecasters.

A cooling trend was expected to begin by the weekend.

–City News Service