Marine Weather and Tide Forecast for Palm Springs, CA

DISCUSSION
FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES...

Through tonight there will be northeast winds of 20 to 30 mph with gusts to 45 to 55 mph along and below the coastal slopes of the mountains. Winds will increase for Thursday, with northeast winds of 30 to 40 mph with gusts to 60 to 75 mph and with isolated gusts to 85 mph for the San Diego County mountains. Winds will slowly decrease into Friday morning. Overnight humidity recovery will be poor Thursday night into Friday, with relative humidity only reaching 15 to 20 percent for inland locations. Lowest daytime humidity will fall to around 5 percent Thursday afternoon and around 5 to 10 percent on Friday afternoon. A few degrees of cooling is expected for Thursday away from the coast. Then cooler on Friday for coastal areas with the mountains a few degrees warmer.

An upper level low pressure system from the north will move into central California on Saturday. The low will slowly move southward into Southern California by Sunday or Monday. Most of the uncertainty in the model ensemble solutions surrounds the timing of the low, with lesser uncertainty in the amplitude of the low. Most of the ensemble solutions for Sunday and Monday (80 and 75 percent respectively) keep the low more to the west which would be a favorable track for precipitation across the area. Current forecast keep precipitation chances through Tuesday. Through Tuesday night there is a 50 to 70 percent chance of one-quarter inch or more of precipitation for the coast and valleys, with an 80 percent chance of one-quarter inch or more of rainfall/liquid-equivalent in the mountains. In the mountains there is a 30 to 40 percent chance for three-quarters of an inch or more of rainfall/liquid-equivalent. Current forecast has the highest and most widespread chances of rain Saturday night into Sunday.

This is expected to be a cold system with snow level of 4000 to 5000 feet on Saturday afternoon will fall to around 3500 to 4000 feet on Sunday. Current forecast keeps the snow level 3500 to 4000 feet through Tuesday. Ensemble guidance is indicating that snow could accumulate in the High Desert, with multiple members of both the ECMWF and GFS showing some amount of accumulating snow although there is a wide range of solutions when it comes to how much snow will accumulate. NBM chances for 12 inches or more of snowfall in the mountains for the weekend is around 80 percent for elevations above 7000 feet.

There remains uncertainty in the forecast for early next week.
Much of the uncertainty surrounds the timing of how quickly the low pressure system will depart to the east. Due to the cold nature of the system, below average temperatures are forecast for Saturday through Wednesday. By Wednesday most ensemble solutions have the low to our east with a ridge of high pressure building over the West Coast of the US.

AVIATION
222100Z....SCT-BKN high clouds will continue today and tonight.
Areas of northeast winds 25-35 kts mainly in foothills and adjacent valleys will continue today and tonight, generating pockets of LLWS and mod up/downdrafts in lee of mountains. East to northeast winds strengthen and become more widespread early Thursday morning, peaking early Thursday afternoon with gusts 30-45 kts, locally stronger in foothills and adjacent valleys, before gradually subsiding through Thursday night.

NWS San Diego is aware of limited communications of observations from KTRM since January 8th. We are working with the FAA to address this issue.

MARINE
Offshore winds become breezy late tonight through Thursday. There is a slight chance of thunderstorms late Saturday associated with a regional storm system. Any thunderstorms could produce locally gusty, erratic winds and briefly hazardous conditions. Otherwise, prevailing winds and seas are not expected to generate hazardous marine conditions through Sunday.

FIRE WEATHER
Critical fire weather conditions will continue through Friday morning. The strongest winds are expected during the day on Thursday with northeast winds of 30 to 40 mph with gusts to 60 to 75 mph and isolated gusts to 85 mph for the San Diego County mountains. Lowest daytime humidity will fall to around 5 percent Thursday and around 5 to 10 percent on Friday with poor overnight recovery.

Substantial recovery in humidity is expected during the weekend with widespread wetting rain and mountain snow.

SKYWARN
Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions.



SGX WATCHES/WARNINGS/ADVISORIES
CA...Red Flag Warning until 10 AM PST Friday for Orange County Inland Areas-Riverside County Mountains-Including The San Jacinto Ranger District Of The San Bernardino National Forest-San Bernardino County Mountains-Including The Mountain Top And Front Country Ranger Districts Of The San Bernardino National Forest-San Bernardino and Riverside County Valleys -The Inland Empire-San Diego County Inland Valleys-San Diego County Mountains-Including The Palomar And Descanso Ranger Districts of the Cleveland National Forest-San Gorgonio Pass Near Banning-Santa Ana Mountains-Including The Trabuco Ranger District of the Cleveland National Forest.

High Wind Warning from 6 AM to 6 PM PST Thursday for Orange County Inland Areas-Riverside County Mountains-San Bernardino County Mountains-San Bernardino and Riverside County Valleys-The Inland Empire-San Diego County Mountains- San Diego County Valleys-San Gorgonio Pass Near Banning- Santa Ana Mountains and Foothills.

PZ...None.