Very strong surface high pressure over the Great Basin and extreme packing of the isobars along the crest of the Transverse and Peninsula Ranges resulted in an extended period of very strong, damaging, Santa Ana winds in the mountains and valleys of Southern California. During the morning of the 22nd, the pressure gradient averaged an impressive 0.2 to 0.3 mb/mile across the mountain crests. For example, a 10 mb pressure gradient was observed over a distance of just 45 miles between Ontario and Apple Valley, a 9 mb pressure gradient was observed over a distance of just 35 miles between Borrego Springs airport and Ramona airport, and an 8 mb offshore pressure gradient was observed over a distance of just 25 miles between Rialto airport and Big Bear City airport. Widespread wind gusts in excess of 65 mph with local gusts near 80 mph were reported in the Inland Empire, San Bernardino foothills, Santa Ana mountains and foothills, and San Diego County mountains and foothills. Several locations in and below passes and canyons experienced tropical storm force winds or greater for more than 36 hours.
A peak wind gust of 85 mph was measured at Fremont Canyon, 79 mph at Palm Elementary in San Bernardino, 75 mph at Descanso and Mira Loma, 74 mph at Fallbrook and Rancho Cucamonga, 69 mph at Potrero, 67 mph at Beaumont, 66 mph at Ontario, 63 mph at Case Springs and El Cariso, 62 mph at Campo prior to the power outage, 59 mph at Julian and Alpine, and 58 mph at Cameron and Chino.
The strong winds downed countless trees and power poles, damaged many roofs, damaged fences, damaged or destroyed outbuildings, damaged or destroyed road signs, overturned several high-profile vehicles, generated large dust storms, and fanned the flames of several large and devestating wildfires.

High Wind in SAN DIEGO COUNTY VALLEYS, CALIFORNIA
From 21-OCT-07 19:14:00 to 22-OCT-07 09:14:00 (PST-8)
Magnitude: 64.00 MG
Property damage: 10.00M
Crop damage: 0.00K
Reported by: Mesonet

Wind gusts in excess of 70 mph toppled trees, damaged countless roofs, snapped power poles, and overturned high profile vehciles. Numerous large oaks and Eucalyptus were snapped at their bases. Road signs that were not consumed by fire were toppled or snapped in half by the high winds. A few outbuildings were destroyed and several more were severely damaged. Downed power lines resulted in several large and devestating wildfires.
At Potrero, wind gusts of 60 mph or greater were observed for 11 hours (6 consecutive hours), and wind gusts in excess of 50 mph or greater were observed for 25 hours (17 consecutive hours).

High Wind in SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS - THE INLAND EMPIRE, CALIFORNIA
From 21-OCT-07 03:18:00 to 22-OCT-07 11:12:00 (PST-8)
Magnitude: 69.00 MG
Property damage: 35.00M
Crop damage: 0.00K
Reported by: Mesonet

A strong Santa Ana wind event caused widespread wind damage across the Inland Empire. Wind gusts in excess of 70 mph snapped power poles, toppled trees, overturned big rigs, and damaged roofs. In one of the hardest hit areas, the wind caused an estimated $2.6 million in damage at Mt. San Jacinto College. Many of the surrounding homes sustained minor to major roof damage. Elswhere, a portion of the 215 freeway between Devore and I-10 was shut down as a result of the high wind, overturned big rigs, and blowing dust.
Wind gusts of 50 mph or greater were observed for 19 consecutive hours at Beaumont and 14 hours (5 consecutive hours) at Ontario. A peak wind gust of 79 mph was measured at Palm Avenue Elemntary School in San Bernardino.

High Wind in SANTA ANA MOUNTAINS AND FOOTHILLS, CALIFORNIA
From 21-OCT-07 02:30:00 to 22-OCT-07 13:30:00 (PST-8)
Magnitude: 74.00 MG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Mesonet

At Fremont Canyon, wind gusts of 70 mph or greater were observed for 23 hours (19 consecutive hours), and wind gusts of 60 mph or greater were observed for 35 hours (25 consecutive hours). Six wind gusts in excess of 80 mph were measured by the Fremont Canyon RAWS, including a peak wind gust of 85 mph.
At Case Springs, wind gusts of 50 mph or greater were observed for 27 hours (11 consecutive hours), and wind gusts of 40 mph or greater were observed for 53 hours (50 consecutive hours).
Due to the lack of structures and people within zone 57, no reports of damage were received.

High Wind in SAN DIEGO COUNTY VALLEYS, CALIFORNIA
From 23-OCT-07 06:14:00 to 23-OCT-07 07:14:00 (PST-8)
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

High Wind in SAN DIEGO COUNTY MOUNTAINS, CALIFORNIA
From 21-OCT-07 10:52:00 to 22-OCT-07 11:33:00 (PST-8)
Magnitude: 65.00 MG
Property damage: 10.00M
Crop damage: 0.00K
Reported by: Mesonet

Wind gusts in excess of 70 mph toppled trees, damaged countless roofs, snapped power poles, and overturned high profile vehciles. Numerous large oaks and pines, some greater than 2 feet in diameter, were snapped at their bases. One large pine was seen hanging upside down from the top of some power lines near Wynola. Road signs that were not consumed by fire were toppled or snapped in half by the high winds. A few outbuildings were destroyed and several more were severely damaged. Downed power lines resulted in several large and devestating wildfires.
At Julian, wind gusts of 50 mph or greater were observed for 18 consecutive hours while wind gusts of 40 mph or greater were observed for 39 hours (29 consecutive hours).
At Descanso, wind gusts of 50 mph or greater were observed for 14 hours (4 consecutive hours) while wind gusts of 45 mph or greater were observed for 26 hours (15 consecutive hours).

High Wind in SANTA ANA MOUNTAINS AND FOOTHILLS, CALIFORNIA
From 22-OCT-07 23:30:00 to 23-OCT-07 06:30:00 (PST-8)
Magnitude: 65.00 MG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Mesonet

High Wind in ORANGE COUNTY COASTAL AREAS, CALIFORNIA
From 21-OCT-07 04:00:00 to 22-OCT-07 10:00:00 (PST-8)
Magnitude: 56.00 EG
Property damage: 5.00M
Crop damage: 0.00K
Reported by: Newspaper

Santa Ana winds toppled trees, brought down power lines, and knocked out power to thousands in many parts of Orange County. The strongest winds were felt along the foothills of the Santa Ana mountains and near the Chino Hills area.