Los Angeles, June 15 : California is bracing for its first major heatwave of the year this week and the extreme drought conditions could cause more wildfires, authorities have warned. High pressure building over the Southwest would increase temperatures and it get even hotter as the week goes on, Xinhua news agency quoted the National Weather Service (NWS) as saying on Monday. Temperatures could reach as high as 44.4 degrees Celsius in Antelope Valley in northern Los Angeles County this week. "Tuesday through Thursday should be the hottest, when highs between 37-41 degrees and minimum humidities between 5 and 15 per cent will be common over most mountains and lower mountains," the NWS tweeted. Temperatures would soar in the San Joaquin and Sacramento valleys in northern California by Thursday, the NWS Sacramento said. Highs were supposed to range from 37.8 degrees Celsius to 45 degrees in the mountain area near the capital city of the state. The heatwave would worsen the extreme drought hitting several areas in the Golden State. Last week, the National Oceanic and Atmospheric Administration warned of "extreme and exceptional drought" conditions in northern and central California, as well as along the central California coast. Moreover, the heat wave and drought conditions could lead to more wildfires as hundreds of acres continued to burn across California on Monday. There are currently four active wildfires of interest in the state, including the Beale Fire, the Goose Fire, the Flats Fire and the Farm Fire, according to the California Department of Forestry and Fire Protection. As of Monday, Cal Fire reported that 17,273 acres had been scorched in 3,151 incidents so far this year. Red flag warnings would be in effect Monday evening through Wednesday morning along the south Santa Barbara County coast and critical fire weather conditions were also expected in southeastern California. /IANS