December 30, 2020
There is a considerable amount of ground fog, mainly from a Visalia/Tulare line northward through Merced County. A very temporary very weak zone of upper level high pressure is currently moving through, creating a weak warm air inversion above the valley floor. The freezing level has risen from 4,700 feet yesterday to 9,000 feet this morning, according to the latest data from Oakland.
In the meantime, higher level clouds are increasing over northern California from a weak weather system which is racing south/southeast into the Pacific Northwest. Most models project the system’s main dynamics will move into the Great Basin, however northern and Central California will be on the far western fringe which will spread cloud cover over the valley. A few sprinkles are even possible from Fresno County north Thursday and Thursday night.
Beginning Friday, a flat zone of upper level high pressure over the eastern Pacific will build into the southern 2/3 of California. The pattern will become zonal with a west to east flow steering Pacific storms into the Pacific Northwest and roughly the northern 1/3 of California. The storm track will begin to sag slowly southward late Sunday into Monday. The chance for mainly light precipitation will begin Monday, lasting into Tuesday, mainly from the Kern County line north.
I’m really keeping my fingers crossed on this one as models are trending towards a possibly very wet pattern from roughly Wednesday through Friday of next week. Some models are depicting an atmospheric river of air moving into central and even southern California with potentially heavy amounts of precipitation along the Sierra Nevada and decent amounts of precipitation on the valley floor.
Forecast: Areas of dense fog and low clouds this morning. increasing higher clouds this afternoon. Mostly cloudy tonight through Thursday night with a chance of sprinkles, mainly from Fresno County north. Partly cloudy Friday with areas of night and morning fog and low clouds. Variable cloudiness Friday night through Sunday with areas of night and morning fog and low clouds. Increasing cloudiness Sunday night with an increasing chance of light rain Monday into Tuesday, mainly north of Kern County. Rain becoming likely Wednesday.
Short Term:
| Madera 55/35/54/32/55 | Reedley 56/34/54/33/55 | Dinuba 54/34/54/32/54 |
| Porterville 56/34/55/33/56 | Lindsay 54/33/54/32/55 | Delano 56/35/54/33/56 |
| Bakersfield 56/39/51/37/57 | Taft 53/42/54/43/57 | Arvin 54/36/51/35/57 |
| Lamont 56/35/53/35/57 | Pixley 56/34/53/33/57 | Tulare 53/33/53/31/54 |
| Woodlake 55/34/54/33/55 | Hanford 56/35/54/34/55 | Orosi 54/33/54/32/54 |
Seven Day Forecast:
| Saturday
AM fog/partly cloudy 34/56 |
Sunday
AM fog/mostly cloudy 38/59 |
Monday
Light rain 46/58 |
Tuesday
AM showers possible 42/59 |
Wednesday
Rain likely 50/61 |
Two Week Outlook: January 4 through January 10: This is the most encouraging two week model forecast I’ve seen for a while. It projects above average precipitation for all of California as the storm track migrates southward. Temperatures will be near to marginally below average.
January: This model doesn’t really show a trend for temperatures at all. We’ll call it near average this time around. Not surprisingly, it does indicate January will have below average precipitation, as has been the case this La Nina year.
January, February, March: This model does not really offer much hope for a decent rainy season as below average precipitation is indicated over the Golden State. Temperatures over this 90 day period will be generally above seasonal average.
Winds Discussion: Winds through Saturday will be generally at or less than 10 MPH late mornings and afternoons and at or less than 5 MPH during the night and early morning hours with extended periods of near calm conditions.
Rain Discussion: There is a chance of a few sprinkles Thursday and Thursday night to ring in the new year. Nothing measurable is anticipated, however. During the second half of the weekend, the storm track will be running from west to east into the Pacific Northwest and northern California. Models show the first in hopefully a series of storms moving into central California Monday into Tuesday with generally light amounts of precipitation. The more encouraging outlook is for the Wednesday through Saturday period of next week. A strong low is projected to be off the Oregon/northern California coast with possibly an atmospheric river of air moving into central and southern California. If this occurs, it is one of the wetter patterns we deal with in the winter months. Hopefully, we will receive heavy mountain snow and significant rain on the valley floor.
Frost Discussion: All locations will be above 32 degrees tonight, however riverbottom and low frost pockets could potentially drop to 31 to 32 degrees. A weather system digging into the interior west will spread increasing amounts of cloud cover over the region later this afternoon with mostly cloudy skies tonight and possibly well into Thursday night, as well. Friday morning’s outcome will be determined by the exit strategy of the cloud cover. Upper 20s and lower 30s would be possible if skies open up during the early morning hours. My feeling, however, is most locations will be in the low to mid 30s. we will be under a progressively warmer flow aloft Saturday through Sunday which will spread variable clouds over central California. If skies open up, areas of night and morning fog will also come into play. From Sunday and through at least Friday of next week, temperatures will be above freezing due to an active weather pattern.
Air Quality Expectations: The San Joaquin Valley Air Pollution Control District has issued the following warning(s) for December 29, 2020:
The air quality for is moderate for the entire growing area.
The District’s Real-time Air Advisory Network (RAAN) can be used to track air quality at any Valley location by visiting myRAAN.com. The option to use a specific address is available.
In addition, anyone can follow air quality conditions by downloading the free “Valley Air” app on their mobile device
Afternoon Dew Points Today: Low to mid 40s. Low to mid 40s.
Actual Humidity Range Yesterday: Delano, 90%/55% Porterville, NA
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 60%, tomorrow 20%. Bakersfield: Today: 70% Tomorrow: 30%
ET Rates Over the Past Seven Days: ET INORMATION IS UNAVALIABLE UNTIL FURTHER NOTICE. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 52, Parlier 48, Blackwell 55, Arvin, 51, Orange Cove 51, Porterville 51, Delano 44
Record Temperatures: 67/24. Average Temperatures: 53/35
Heating Degree Days This Season: 899 courtesy of the NWS
Average Temperature for this month So Far: 47.0 +2.3 courtesy of the NWS
Precipitation: Seasonal total for Fresno, 1.42, or -1.91, Month to Date: 1.14, or -.49
Precipitation for Bakersfield, Season, .70, +or- -1.18 Month to date .31, or -.63
Water year season is from October 1st through September 30.
Chilling Hours November 1st through February 28: Orange Cove, 510, Parlier, 600, Arvin, 469, Belridge, 546, Shafter, 555, Stratford, 577, Delano, 620, Porterville, 662
Hours at 45 or below 45. Courtesy UC Davis
Sunrise: 7:11 am Sunset: 4:53 pm Hours of Daylight: 9:42
Yesterday’s Weather
MCE : Merced 153 : DH1600 / 54 / 33 / 0.00 /
MAE : Madera 253 : DH1600 / 56 / 32 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 56 / 38 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 58 / 34 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 59 / 49 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 56 / 42 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 57 / 35 / 0.00 /
ATEC1 : Avenal 787 : DH1552 / 57 / 36 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 54 / 36 / 0.00 /
TFTC1 : Taft 759 : DH1600 / 52 / 46 / M /
LOSC1 : Los Banos 120 : DH1600 / 58 / 37 / 0.00 /
Rainfall: 24hr W.Y. % Last Y. % Ave. Year ave.
STOCKTON 0.00 1.83 40 4.32 94 4.58 14.06
MODESTO 0.00 1.52 39 3.23 82 3.93 13.11
MERCED 0.00 2.23 66 0.00 0 3.37 12.50
MADERA 0.00 0.77 21 0.00 0 3.60 12.02
FRESNO 0.00 1.42 43 0.00 0 3.33 11.50
HANFORD 0.00 0.65 22 0.00 0 2.96 10.10
BAKERSFIELD 0.00 0.70 37 0.00 0 1.88 6.47
BISHOP M M M M M M 5.18
SALINAS 0.00 0.87 23 5.06 134 3.77 12.83
PASO ROBLES 0.00 0.98 28 5.93 170 3.49 12.78
SANTA MARIA 0.00 1.76 45 4.05 104 3.89 13.95
Next report: December 30/pm