February began with a weak upper-level ridge over the central California interior. The ridge kept a low-level inversion over the central and southern San Joaquin Valley, resulting in areas of Tule fog through the first four days of the month. The worst fog occurred during the morning of February 3rd, with a Dense Fog Advisory being issued.
An upper-level low-pressure trough moved into northern California on February 2nd. While the trough had a minimal impact on interior central California, it did provide enough dynamics to bring some very light rain to Naval Air Station Lemoore during the night of February 1st-2nd. The trough axis moved through central California late on February 2nd into the morning of the 3rd.
Computer forecast models on February 3rd began indicating that the storm forecast for the 6th-7th would be a cold system, with snow levels falling to around 4500 feet by the morning of the 7th. This prompted the issuance of a Winter Storm Watch for the Southern Sierra Nevada and the Tehachapi Mountains.
The Pacific storm moved into California during February 5th-7th, with the first rain actually occurring during the evening of the 4th in the warm sector ahead of the cold front. The storm brought up to an inch of rain to the central and southern San Joaquin Valley, and between 2 and 3 inches of rain to the Southern Sierra Nevada. A spotter at Hume Lake measured 1.08 inch of rain in an 18-hour period, from midnight to 6 PM on February 5th. For the 24-hour period from 10 PM on the 4th to 10 PM on the 5th, Wishon Dam recorded 1.53 inch of rain, and Oakhurst received 1.09 inch.
As the snow level dropped���bottoming out between 4000-4500 feet during the night of February 6th-7th���and the rain turned to snow, up to 2 feet of snow fell in the Southern Sierra Nevada above 6000 feet. Gusty winds also occurred in the Sierra Nevada and Tehachapi Mountains. At the CHP Weigh Station on I-5 at the base of the Grapevine, gusty winds around 60 mph were measured during the morning hours of Feb 5th.

Winter Storm in KERN CTY MTNS, CALIFORNIA
From 05-FEB-10 05:00:00 to 05-FEB-10 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Winter Storm in S SIERRA MTNS, CALIFORNIA
From 04-FEB-10 18:00:00 to 07-FEB-10 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in TULARE CTY MTNS, CALIFORNIA
From 04-FEB-10 18:00:00 to 07-FEB-10 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong Wind in SE KERN CTY DESERT, CALIFORNIA
From 07-FEB-10 04:15:00 to 07-FEB-10 12:30:00 (PST-8)
Magnitude: 41.00 MG
Property damage: 0.50K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in W CENTRAL S.J. VALLEY, CALIFORNIA
From 03-FEB-10 00:00:00 to 03-FEB-10 10:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in E CENTRAL S.J. VALLEY, CALIFORNIA
From 03-FEB-10 00:00:00 to 03-FEB-10 10:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in SW S.J. VALLEY, CALIFORNIA
From 03-FEB-10 00:00:00 to 03-FEB-10 10:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in SE S.J. VALLEY, CALIFORNIA
From 03-FEB-10 00:00:00 to 03-FEB-10 10:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Heavy Rain in FRESNO, CALIFORNIA
From 04-FEB-10 22:00:00 to 05-FEB-10 22:00:00 (PST-8)
Location: BALCH CAMP
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Twenty four hour storm rainfall was 1.53 inches at Wishon Dam.