December 16, 2018
Summary: Clouds are increasing over the northern half of the valley at this hour. Generally light precipitation is occurring from roughly a Bay Area/Sacramento line north. The main frontal system is still just off the northern California coast. It will spread significant amounts over the northern third of the state with possibly one-half inch total from roughly Merced County north. Rain will spread over Fresno and Madera Counties this evening then break off into showers over the remainder of the valley after midnight, continuing through most of Monday morning.
Satellite imagery is picking up an enhanced area of cloud cover along the frontal zone off shore. This is projected to move through the northern half of the valley during the early morning hours. This could add enough dynamics to the atmosphere for isolated thunderstorms from Fresno County northward.
By Monday evening, the front will have moved into western Nevada, so most if not all the precipitation will be over by midday Monday with only a minimal chance of lingering showers for a time, mainly in the south valley.
Beginning Tuesday, a strong upper high will develop off the southern California coast and will expand northward. As it expands, the storm track will move back into the Pacific Northwest. As upper level high pressure builds aloft, a typical wintertime warm air inversion will develop, setting the stage for widespread morning fog, lifting into a low overcast from late morning through the afternoon hours with possible partial clearing in some areas during the afternoon. A weak trough will move through late Thursday night and Friday morning. For now, I’m betting it won’t be enough to break up the inversion.
From this weekend through Christmas Day, a flat zone of high pressure will cover the eastern Pacific and California, maintaining a dry weather regime. Models are still pointing towards a possible change in the pattern for about the 27th. A strong westerly flow is projected to move under a big low off the coast of the Pacific Northwest. In theory, this could bring a good deal of precipitation to northern California and at least a chance further south.
Forecast: Increasing cloudiness this morning. Mostly cloudy this afternoon with a small chance of light showers from Fresno County north. Rain will spread into Fresno and Madera Counties this evening then break off into showers over the south valley tonight through Monday morning. Mostly to partly cloudy Monday afternoon through Tuesday morning. Partly cloudy Tuesday afternoon. Widespread fog developing Tuesday night and Wednesday morning with clearing possible in the afternoons. There will be widespread low clouds and/or fog Thursday through Sunday with a chance of partial afternoon clearing each day.
Short Term:
| Madera 63/49/60/41/58 | Reedley 65/50/60/42/58 | Dinuba 63/48/59/41/57 | |
| Porterville 65/49/62/41/59 | Lindsay 65/48/59/40/59 | Delano 66/50/61/42/60 | |
| Bakersfield 67/51/61/46/65 | Taft 66/51/62/50/62 | Arvin 68/51/62/43/62 | |
| Lamont 67/51/62/43/61 | Pixley 65/50/60/41/60 | Tulare 64/48/60/40/59 | |
| Woodlake 64/49/60/40/59 | Hanford 65/50/60/41/59 | Orosi 64/47/60/41/58 | |
Seven Day Forecast:
| Wednesday
AM fog/PM sun 42/54 |
Thursday
AM fog/PM sun 44/52 |
Friday
AM fog/PM sun 42/52 |
Saturday
AM fog/PM sun 43/5+3 |
Sunday
AM fog/PM sun 42/55 |
Two Week Outlook: December 23 through December 29: This model seems to be leaning towards a pattern that would bring the storm track back into northern California and possibly central California. By and large, a westerly flow aloft would sweep in from the Pacific, potentially guiding storms into northern California and possibly further south. Temperatures would range above average for late December.
December: It’s been quite some time since this model has actually projected above average precipitation, but the good news is that is the case. It appears the dominant pattern for the month will maintain winds generally out of the west or northwest, which would favor above average temperatures.
December, January, February: It’s been a long time since the 90 day outlook projected above average precipitation for December through February, in other words the winter months. It also continues the better than even chance that over the next three months, temperatures will largely be above average. However, like any winter there will be below average periods as well.
Winds: Winds will be out of the southeast later today at 5 to 15 MPH, continuing tonight with local gusts to 20 MPH possible. By midday Monday, winds will be out of the northwest at 5 to 15 MPH, diminishing later Monday evening with light winds returning late Monday night through Wednesday.
Rain: There is a small chance of a few light showers as far south as Fresno County by late afternoon. As the front approaches later this evening, rain will spread into Madera and Fresno Counties with showers spreading over the south valley. The rain will end, at least in most areas, by midday Monday with only a minimal chance of lingering showers in the south valley Monday afternoon. Dry weather will return Monday night and last for the next seven to ten days, if models are correct.
Rainfall amounts from the current system should average between .25 and .33 in Fresno and Madera Counties, upwards to .25 in Tulare County from roughly Porterville north, .10 to .20 in Kings County with generally .10 or less over the valley portion of Kern County.
Frost Discussion: All locations will be above freezing tonight. Above freezing conditions will continue Tuesday morning and for the remainder of the week. Nothing on medium range models suggests a cold pattern any time soon.
Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: Mid to upper 40s.
Humidity: Porterville: 60%/100%, Bakersfield: 45%/90%
Actual Humidity December 15, 2018: Delano, 95%/48%, Porterville, 96%/38%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 40%, tomorrow 0% Bakersfield: Today: 60% Tomorrow: 0%
ET Rates Over the Past Seven Days: Stratford .17, Parlier .19, Blackwell .24, Lindcove .20, Arvin .29, Orange Cove .21, Porterville .20, Delano .23 Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 56, Parlier 53, Blackwell 54, Lindcove, 59, Arvin, 53, Orange Cove 54, Porterville 52, Delano 51
Record Temperatures: 70/25. Average Temperatures: 54/35
Heating Degree Days this Season: 559 -234
Courtesy of the NWS
Average temperature for December so far: 49.0 +3.8
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 1.92 season. or -.49, Month to Date: .15 -.56
Since Oct 1, 2018, Bakersfield: 1.20, or -.18. Month to Date: .52 +.08
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, 262, Parlier, 285 , Arvin, 220 Shafter, 301 Stratford, 255, Delano 278, Lindcove, 388, Porterville, 539
. Hours at 45 or below 45.
Sunrise: 7:05 am Sunset: 4:45 pm. Hours of Daylight: 9:41
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 65 / 36 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 66 / 39 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 66 / 34 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1500 / M / 36 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 66 / 41 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 65 / 35 / 0.00 /
ATEC1 : Avenal 787 : DH1552 / 65 / 38 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 67 / 35 / 0.00 /
TFTC1 : Taft 759 : DH1552 / 64 / 46 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr Season % L.Y. % Ave. Ave. yearly total
STOCKTON 0.00 3.87 111 0.91 26 3.48 14.06
MODESTO 0.00 3.05 105 0.98 34 2.91 13.11
MERCED 0.00 2.69 107 1.03 41 2.52 12.50
MADERA 0.00 2.42 91 0.32 12 2.66 12.02
FRESNO 0.00 1.92 80 0.37 15 2.41 11.50
HANFORD 0.00 1.71 88 0.37 19 1.94 10.10
BAKERSFIELD 0.00 1.20 87 0.03 2 1.38 6.47
BISHOP 0.00 1.31 117 0.16 14 1.12 5.18
SALINAS 0.00 3.87 137 0.75 27 2.82 12.83
PASO ROBLES 0.00 2.84 116 0.25 10 2.45 12.78
SANTA MARIA 0.00 1.95 69 0.09 3 2.81 13.95
Next report: Monday morning/December 17