INTERAGENCY FIRE WEATHER CENTER – PREDICTIVE SERVICES UNIT

 

TUESDAY, SEPTEMBER 25, 2018

SOUTHERN CALIFORNIA GEOGRAPHICAL AREA COORDINATION CENTER

RIVERSIDE, CALIFORNIA

Weather Discussion:

 

High pressure will bring sunnier and warmer weather today through Thursday, but another trough will generate cooler weather this weekend.

 

·         Much warmer weather will develop through midweek.  Highs will climb 5-10 degrees today, and by Wednesday and Thursday, most valleys will reach the 95-100 degree range.

·         Light offshore winds of 10-15 mph will be possible late tonight into Wednesday morning, mainly from Los Angeles County southward.

·         Minimum humidity will drop into the single digits from the valleys to the mountains below 6,000 feet Wednesday and Thursday.

·         Onshore, southwest winds of 20-30 mph with gusts approaching 50 mph will be possible in and near the desert Friday into the weekend.

·         Below normal temperatures expected both Saturday and Sunday with widespread marine layer stratus developing.

 

Fire Potential Discussion:

 

·         Large fire potential will be elevated across the central coast area southward into most of Southern California Wednesday and Thursday due to much warmer and drier weather.

·         All fuel types will be highly receptive to ignition during peak heating hours.  Expect rapid rates of spread and near total consumption with any new start away from the immediate coast through midweek.

·         Dead fuel moisture is close to record low readings.  Live fuels area critically dry over most areas.

·         Elevated large fire potential will shift to the desert interface areas Friday into the weekend due to strong winds.  The rest of the area will see lower large fire potential due to cooler and much more humid weather.

·         Moderate IA is expected through Thursday, then light IA is expected the rest of the week.

 

For additional fuel and weather information, including the Santa Ana Wildfire Threat Index, please visit:

 

http://gacc.nifc.gov/oscc/predictive/weather/index.htm