January 28, 2021
The atmospheric river of air has not budged over the past 36 hours. It has been coming ashore from Ventura County northward through Monterey County, sweeping northeastward across the San Joaquin Valley with relentless rain, mostly light to moderate. From Kings County northeastward through Fresno, Madera, and Mariposa Counties. As expected, Kern County and much of Tulare County have been under a strong rain shadow. However, as the off shore low begins to pivot towards the southern California coast later today, the rain line will move slowly southward with precipitation finally overspreading eastern Tulare County and Kern County. Rain, heavy at times, can be expected into the morning hours Friday then will turn to showers, finally ending this event by Friday evening.
I have some of the staggering rainfall amounts in the rain discussion below.
A zone of weak upper level high pressure will fill in and dominate our pattern later Friday night through Monday. The next trough of low pressure will dig southward from the Gulf of Alaska, spreading showers over the valley late Monday night through Tuesday.
Beginning Wednesday, a mammoth high will build over the eastern Pacific Ocean with a winter storm possibly developing over the Desert Southwest. Models show a north to south flow over California along the eastern rim of the high with arctic air flowing into the interior west. This morning’s models look a little better as far as avoiding a freeze situation goes.
We’ll tweak this forecast in the coming days. But, temperatures will drop to below average in the coming days with possibly some frost nights.
Forecast: Rain, possibly heavy at times this morning in Madera, Fresno, and Kings Counties. Cloudy over most of Tulare and Kern Counties. The rain will slowly spread into the south valley this afternoon. Rain tonight, heavy at times, throughout the valley. The rain will turn to showers Friday, tapering off by evening. Mostly cloudy Friday night and Saturday morning. partly cloudy Saturday afternoon through Monday morning. increasing clouds late Monday. Showers becoming likely late Monday night through Tuesday. A chance of showers Tuesday night. partly cloudy Wednesday. Mostly clear to occasionally partly cloudy Wednesday night and Thursday.
Short Term:
| Madera 54/42/56/37/57 | Reedley 55/43/56/35/57 | Dinuba 53/42/55/35/56 |
| Porterville 58/43/56/37/56 | Lindsay 57/42/56/35/57 | Delano 59/43/55/39/57 |
| Bakersfield 61/45/55/41/55 | Taft 59/48/55/44/57 | Arvin 61/43/54/39/58 |
| Lamont 60/43/56/39/57 | Pixley 59/43/56/36/57 | Tulare 54/42/55/35/55 |
| Woodlake 55/41/56/35/56 | Hanford 54/42/56/36/58 | Orosi 55/41/56/34/56 |
Seven Day Forecast:
| Sunday
Partly cloudy 36/61 |
Monday
Increasing clouds 40/60 |
Tuesday
Showers likely 43/57 |
Wednesday
Partly cloudy 33/53 |
Thursday
Mostly clear 32/55 |
Two Week Outlook: February 4 through February 10: This model shows only a minimal chance of rain during this time frame. It also indicates we will be on the western side of a cold low, resulting in below average temperatures.
February: Both the 30 and 90 day outlooks reflect a La Nina pattern with below average precipitation over the southern 2/3 of California and above average precip over parts of the Pacific Northwest and northern California. Temperatures should be close to seasonal averages.
February, March, April: Precipitation will continue to be above average over the Pacific Northwest and roughly the northern ¼ of California with the southern 2/ 3 of California having below average precipitation. Temperatures should be marginally above average.
Winds Discussion: Strong differences in pressure will continue to spawn strong east to southeast winds in Kern County with gusts exceeding 50 MPH from Taft on the west to Lamont on the east. Gusts in excess of 40 MPH are possible as far north as Bakersfield.
Southeast winds will continue along the west side of the valley at 15 to 35 MPH with stronger gusts, decreasing by evening. North of Kern County along the east side, winds will be mainly out of the southeast at 10 to 20 MPH with stronger gusts. Throughout the valley tonight, winds will be mainly out of the east to southeast at 10 to 20 MPH with stronger gusts.
By late Friday, winds will be out of the northwest at 8 to 15 MPH, diminishing Friday night with light winds Saturday.
Rain Discussion: Anywhere from 7 to 10 inches of rain have fallen in the mountainous terrain above San Simeon. Two to four inches have fallen just west of the I-5 at the base of the Coast Range. In the Sierra Nevada, the heaviest so far is 5.80 at Kaiser Point. That is the range that separates Huntington from Edison Lake, which means more than 10 feet of snow has accumulated. Bass Lake has reported 5.60, Yosemite Valley 3.59.
Very little has fallen in the south valley on the valley floor with Bakersfield at just .02, Porterville .08, Lindsay .62, Exeter .26, Tulare .16, Visalia .21, Hanford .28, Lemoore .91, Harris Ranch 1.60, Parlier .36, Del Rey .42, Fresno .49, Panoche Road 2.87, Merced 1.89 and Madera .24.
Relentless light to moderate rain will continue this morning over Kings, Fresno, and Madera Counties with dry weather in Kern and eastern Tulare County. Very slowly, the precipitation shield will begin to move into Kern and Tulare Counties later today. From tonight through tomorrow morning, precipitation will be widespread throughout the valley. The rain will turn to showers later Friday, ending Friday evening everywhere.
Since the rain shadow will slowly end later today, rainfall amounts from now through Friday evening will range between .50 to 1.00 in Kern County and .75 to 1.25 north of Kern County.
Dry weather will begin Friday night with dry weather lasting through Monday. The chance of showers will begin to pick up Monday night, continuing Tuesday. The strongest dynamics of this storm will be over northern California, so precipitation amounts will be generally light. A prolonged period of dry weather will begin Wednesday and possibly lasting for at least a week.
Frost Discussion: All locations will be above 32 tonight. From Saturday morning to Monday morning, it’s possible the coldest low lying frost pockets could dip into the lower 30s with above freezing conditions Tuesday. I’m still watching a potentially colder weather pattern setting up Wednesday of next week. Models this morning don’t look quite as cold. Even so, it appears an arctic air mass will invade the interior west with California under a northerly flow aloft. It’s much too early to talk numbers. Just be advised we may see some frost nights possibly as early as Wednesday of next week.
Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: Mid to upper 40s.
Actual Humidity Range Yesterday: Delano, 95%/41% Porterville, NA
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 0%, tomorrow 20%. Bakersfield: Today: 0% Tomorrow: 0%
ET Rates Over the Past Seven Days:. Stratford .49, Parlier .39, Blackwell Corners .NA, Arvin .49, Orange Cove .38, Porterville .NA, Delano .37. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 52, Parlier 49, Blackwell NA, Arvin, 52, Orange Cove 52, Porterville NA, Delano 45
Record Temperatures: 78/23. Average Temperatures: 57/36
Heating Degree Days This Season: 1366. Varies widely from location to location. courtesy of the NWS
Average Temperature for this month So Far: 48.5 +3.6 courtesy of the NWS
Precipitation: Seasonal total for Fresno, 2.97, or -2.40 or 55% of average. Month to Date: 1.55 or -.35
Precipitation for Bakersfield, Season, 1.10, +or- -1.86 or 37% of average. Month to date .36, or -.64
Water year season is from October 1st through September 30.
Chilling Hours November 1st through February 28: Orange Cove, 776, Parlier, 907, Arvin, 732, Belridge, 837, Shafter, 838, Stratford, 868, Delano, 932, Porterville, 805
Hours at 45 or below 45. Courtesy UC Davis
Sunrise: 7:03 am Sunset: 5:22 pm Hours of Daylight: 10:17
Yesterday’s Weather
MCE : Merced 153 : DH1600 / 47 / 43 / 0.97 /
MAE : Madera 253 : DH1600 / 50 / 43 / 0.20 /
FAT : Fresno Airport 333 : DH1600 / 55 / 43 / 0.35 /
HJO : Hanford Airport 242 : DH1600 / 57 / 44 / 0.25 /
NLC : Lemoore Naval AS 234 : DH1600 / 52 / 45 / 0.66 /
BFL : Bakersfield Airport 496 : DH1600 / 63 / 46 / T /
VIS : Visalia Airport 292 : DH1600 / 59 / 43 / 0.14 /
ATEC1 : Avenal 787 : DH1551 / 53 / 42 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 63 / 44 / 0.02 /
LOSC1 : Los Banos 120 : DH1600 / 47 / 35 / 0.75 /
Rainfall: 24hr W.Y. % Last Y. % Ave. Year ave.
STOCKTON 0.80 3.85 54 5.27 74 7.09 14.06
MODESTO 1.49 3.23 51 3.92 62 6.33 13.11
MERCED 0.91 3.63 61 M M 5.91 12.50
MADERA 0.27 1.32 22 M M 5.98 12.02
FRESNO 0.27 2.93 55 M M 5.37 11.50
HANFORD 0.23 1.46 29 M M 5.02 10.10
BAKERSFIELD T 1.10 37 M M 2.96 6.47
BISHOP 0.10 0.31 12 1.16 45 2.57 5.18
SALINAS 1.54 2.88 47 5.99 97 6.15 12.83
PASO ROBLES 1.36 2.55 42 6.61 109 6.05 12.78
SANTA MARIA 0.91 3.26 51 4.79 75 6.41 13.95
Next report: January 28/pm