From the 23rd until the 26th of the month, an unsettled pattern set up over the state. Temperatures were relatively mild during this time as a cutoff low moving southward along the California coast, while remaining offshore, brought some subtropical moisture to the region, especially over Kern County. More precipitation actually occurred over Kern County during this period than over central portions of the San Joaquin Valley, as the dynamics and moisture that rotated around the upper low off the coast remained mostly over southern California. Gusty southerly winds developed over the Tehachapi Mountains during the early morning of January 24th. Gusts to 68 mph were recorded on Grapevine Peak, and to 56 mph at Bear Valley Springs. At the base of the Grapevine, gusts to around 45 mph were measured at the California Highway Patrol weigh station. Mostly cloudy conditions were otherwise prevalent, but did not prevent dense fog from forming across much of the valley during the mornings of January 25th and 26th.
By the 27th, the cutoff low was finally kicked inland from Baja California and allowed an upper-level trough to move inland over central California and bring cooler air from the Gulf of Alaska. During the afternoon, a convective cell developed over Shaver Lake because of an unstable cold pool of air aloft. This cell dropped ice pellets that briefly snarled traffic on State Route 168; about an inch of ice pellets accumulated on the ground. The trough also brought gusty winds to the Kern County desert from Cache Creek to the mouth of Jawbone Canyon and southwest to the Mojave area. Gusts to around 50 mph were reported during the afternoon of January 27th.
On the 28th, temperatures were below average due to the colder air from the aforementioned trough. High pressure began to build over the eastern Pacific, off the west coast, by the 29th and into the 30th. Daytime temperatures began to rise significantly on the 30th, and reach the mid-60s on the last day of the month.
January has ended with well below average precipitation in the central San Joaquin Valley, as Fresno only had 26.5 percent of normal (0.58 inch compared to the normal of 2.19 inches). Bakersfield actually had more rain in January than Fresno, thanks to the surge of subtropical moisture on the 24th-26th. For the month, Meadows Field had 0.83 inch of rain, or 71.6 percent of the normal of 1.16 inch. These locations were at 50 and 67.9 percent of average, respectively, for the current water year (since July 1st, 2012). The Sierra Nevada snowpack was near or just above average (according to USDA���s western United States mountain snowpack maps) as of the beginning of this month but has likely fallen below average due to the relatively dry conditions that have occurred for much of January.
Temperatures were mainly near average due to a prolonged period of below average daily minimum temperatures combined with above average daily maximum temperatures. Fresno had an average temperature for January of 47.1 degrees, or 0.5 degrees above normal. The average temperature for Bakersfield was 46.7 degrees, or 1.1 degree below normal.

Strong Wind in KERN CTY MTNS, CALIFORNIA
From 23-JAN-13 23:00:00 to 24-JAN-13 10:00:00 (PST-8)
Magnitude: 49.00 MG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in W CENTRAL S.J. VALLEY, CALIFORNIA
From 25-JAN-13 04:00:00 to 25-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in E CENTRAL S.J. VALLEY, CALIFORNIA
From 25-JAN-13 04:00:00 to 25-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in SW S.J. VALLEY, CALIFORNIA
From 25-JAN-13 04:00:00 to 25-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in SE S.J. VALLEY, CALIFORNIA
From 25-JAN-13 04:00:00 to 25-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in W CENTRAL S.J. VALLEY, CALIFORNIA
From 26-JAN-13 04:00:00 to 26-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in E CENTRAL S.J. VALLEY, CALIFORNIA
From 26-JAN-13 04:00:00 to 26-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in SW S.J. VALLEY, CALIFORNIA
From 26-JAN-13 04:00:00 to 26-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Dense Fog in SE S.J. VALLEY, CALIFORNIA
From 26-JAN-13 04:00:00 to 26-JAN-13 11:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Strong Wind in SE KERN CTY DESERT, CALIFORNIA
From 27-JAN-13 12:30:00 to 27-JAN-13 22:00:00 (PST-8)
Magnitude: 43.00 MG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Mesonet