The Heat goes on and on, The Heat goes on and on

LOS ANGELES (CNS) - A red flag warning signifying a high risk of wildfire was issued today for the mountains of Southern California because of high heat, very low humidity and bone-dry vegetation.
Highs once again will reach triple digits in some Southland areas, although the warmest temperatures are expected Thursday through Saturday, and ``a few temperature records could be broken,'' according to an NWS statement.
Even before the red flag warning went into effect, a wildfire broke out Tuesday afternoon in the San Gabriel Canyon section of the Angeles National Forest and had scorched more than 600 acres by this morning.
The National Weather Service said the red flag warning would be in effect from 6 a.m. today until 9 p.m. Friday in the mountains of Los Angeles, Ventura, Santa Barbara and San Luis Obispo counties -- an area that includes the Angeles and Los Padres national forests.
Forecasters blamed the region's newest heat wave on a strong upper-level high-pressure system now over southern New Mexico and expected to reach the Southland by Friday.
``This, in combination with weakening onshore flow, will result in continued warming and drying during the next few days,'' according to an NWS advisory.
During that time, mountain areas will experience 10 hours per day or more of single-digit humidity levels, with little improvement occurring during overnight hours, according to the NWS.
``The combination of long-duration single-digit humidities, hot temperatures and critically dry fuels has prompted the issuance of the red flag warning for the mountains of Southwest California,'' the advisory said.
Valley areas also will be very dry over coming days, but the humidity levels in the valleys are not expected to fall enough below the norm to warrant red flag warnings, according to the NWS.
``The long-duration heat event could pose health hazards for anyone outdoors, especially for the elderly, small children and pets,'' the NWS said in a statement, urging residents to drink plenty of water, wear loose-fitting clothing and stay out of the sun as much as possible.
``Never leave children or pets in cars with the windows up or cracked during the day, even for a very short time, as temperatures can quickly reach lethal levels,'' the statement said.
Some subtropical moisture could return to the region over the weekend, which could send humidity levels back to two-digit territory, although it will remain hot.
The NWS forecast highs today of 83 in Avalon and at LAX; 92 on Mount Wilson; 93 in downtown L.A.; 95 in Long Beach; 98 in San Gabriel and Burbank; 99 in Pasadena; 100 in Lancaster; 101 in Palmdale; 102 in Newhall; and 104 in Woodland Hills.
Temperatures will be even higher Thursday and Friday, return roughly to today's levels on Saturday and begin falling -- by around 5 degrees in some areas -- on Sunday, except in the Antelope Valley, where highs will be in the low 100s through early next week.