December 21, 2019
Summary: Just in case you are counting, winter officially begins at 8:19 this evening as we glory in our 9 hours and 39 minutes of daylight. All this is occurring just in time for a major winter storm bearing down on central California. Already in some locations, the strong winds have begun. Winds have gusted as high as 47 MPH at the CHP office at the bottom of the Grapevine. Maricopa has seen the temperature jump up to 60 degrees 6:00am. And the Rancho Road PG&E station is reporting 55 degrees while just up the road at Lamont, the temperature was 49 degrees.
A significant trough of low pressure stretches from just off the Oregon coast to about 300 miles off the central coast. The current pressure at Salt Lake City is 30.34 inches of mercury while at Eureka, the report is 29.82. this will only increase through the overnight hours and into early Sunday morning, generating strong gusty winds over the Kern County portion of the valley and to a lesser extent up the Interstate 5 corridor. Fortunately, there’s a 13,000 foot barrier named the Sierra Nevada which blocks these winds from affecting the east side of the valley north of Kern County.
A cold front will move through the valley about midday Sunday. Winds will rapidly die off as periods of rain spread over the valley. All of the models indicate strong rain shadows along the west side and in Kern County with possibly some more significant precipitation along the east side, especially nearer the Sierra Nevada foothills. It will be sometime Monday before the backside of the first storm moves through. It still appears we’ll have a dry slot Christmas Eve as Santa makes his rounds. However, following Santa will be phase 2 as the second, colder low moves from north to south right along the coast, spreading bands of showers with snow down into the higher foothills. This system will not carry as much moisture, typically, colder systems don’t, nevertheless more snow will accumulate over the Sierra Nevada with generally light precipitation on the valley floor.
Showers will continue through at least Thursday then most models track the low across southern California and northern Baja on Friday as the chance of showers diminishes rapidly.
Models from the 27th through the 30th indicate upper level high pressure will be over the eastern Pacific and at least the western one-third of the U.S. with a strong surface high over the Great Basin, generating a fairly decent off shore flow. This pattern is a dry one with generally very stable conditions on the valley floor. The air mass behind that last storm will be cold so frosty nights are possible as are increasing amounts of night and morning valley fog.
Forecast: Cloudy through tonight with strong, gusty winds over portions of the west side and the valley portion of Kern County. Periods of rain later Sunday through Monday. A chance of showers Monday night and early Tuesday. Otherwise, partly cloudy Tuesday and Tuesday night. showers at times Christmas Day through Thursday. A chance of showers Thursday night. becoming partly cloudy Friday. Mostly clear to partly cloudy Friday night through Saturday with areas of night and morning fog and low clouds.
Short Term:
Madera 64/42/58/41/52 | Reedley 65/42/59/40/53 | Dinuba 64/41/58/40/51 | |
Porterville 67/44/61/41/52 | Lindsay 66/43/60/40/52 | Delano 68/44/59/42/53 | |
Bakersfield 72/55/65/46/53 | Taft 71/54/65/48/54 | Arvin 69/53/65/46/53 | |
Lamont 70/53/64/46/54 | Pixley 69/44/59/42/52 | Tulare 64/41/59/41/51 | |
Woodlake 65/42/59/40/51 | Hanford 66/43/59/40/52 | Orosi 66/42/59/41/52 |
Seven Day Forecast:
Christmas Eve
Partly cloudy 42/53 |
Christmas Day
Showers likely 41/55 |
Thursday
Showers likely 39/51 |
Friday
Partly cloudy 33/53 |
Saturday
AM fog/PM sun 31/55 |
Two Week Outlook: December 28 through January 3: This model indicates a dominant ridge of high pressure will be over the eastern Pacific and most of the western one-third of the western U.S. The chance of precipitation during this period is quite low with below average temperatures.
December: NOAA always projects warmer than average temperatures during the winter months and has a fairly low batting average. This model follows suit with a projection of above average temperatures, especially over the western U.S. The latest projection for precipitation is near average rainfall will prevail.
January, February, March: This model indicates above average temperatures this winter, but what’s new, especially over the western one-third of the U.S. There are two small notations for below average precipitation. The first is over Louisiana. The second is over northern and central California. Let’s hope this projection is inaccurate, but that’s the official prognosis from NOAA.
Winds: Winds generally east of Hwy 99 and north of the Kern County line jwill be generally out of the east to southeast at 8 to 15 MPH with local gusts to 25 MPH later today through Sunday morning with stronger gusts, mainly from Fresno County north. Winds along the west side of Kings and Fresno Counties will increase out of the southeast this afternoon into Sunday morning at 20 to 35 MPH with stronger gusts. Over the valley portion of Kern County, winds will be out of the east to southeast gusting in excess of 50 MPH near the base of the Tehachapi Mountains, especially below passes and in excess of 35 MPH as far north as Bakersfield. Winds will quickly die off around midday Sunday. On Sunday afternoon through Monday, winds will be generally out of the southeast at 8 to 15 MPH with stronger gusts, especially near precipitation. Winds Tuesday will be variable to around 12 MPH.
Rain: As the cold front approaches Sunday, rain will spread over the valley around midday with periods of rain lasting well into Monday night. rainfall amounts along the west side of the valley will likely be no more than a tenth or two. Over the valley portion of Kern County, rainfall will generally range from .05 to .15 with more near the base of the mountains. North of the Kern County line, rainfall amounts from .20 in Tulare County to as much as .33 in northern Tulare County to Madera County is possible. A brief dry period will greet us Christmas Eve to Christmas Eve night with showers returning Christmas Day and well into Thursday. Rainfall amounts from this system will generally range between .10 to .25 or so. Dry weather will return Friday and may last all the way through the end of the year.
Frost Discussion: All locations will be above freezing through Thursday morning. Low 30s are possible in colder locations Friday morning. the air mass behind the periodic storminess through Thursday is relatively cold as a north/northwest flow develops. Upper 20s and lower30s will certainly be possible beginning next Saturday morning and possible for several days thereafter, unless fog and low clouds take over which is certainly possible.
Afternoon Dew Points Today: Upper 30s to the lower 40s. Kern: Upper 20s to the lower 30s. Humidity values ranging from 40%/80% at Hanford. Bakersfield 20%/35%
Actual Humidity range December 20, 2019: Delano, 99%/46% Porterville, 99%/47%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 0%, tomorrow 0%. Bakersfield: Today: 0% Tomorrow: 20%
ET Rates Over the Past Seven Days: Stratford .39, Parlier .35, Blackwell Corner .38, Arvin .NA, Orange Cove .40, Porterville .31, Delano .34. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 55, Parlier 51, Blackwell 54, Arvin, NA, Orange Cove 53, Porterville 51, Delano 47
Record Temperatures: 71/23. Average Temperatures: 54/35
Heating Degree Days this Season: 654 -244
Courtesy of the NWS
Average temperature for December so far: 51.2- +6.3
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 2.50 season. or -.21. Month to Date: 1.78 +.77
Since Oct 1, 2018, Bakersfield: 1.61, or +.06. Month to Date: .53 -.07
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove 275, Parlier 345, Arvin 223, Shafter 264, Stratford 284, Delano 320, Lindcove 345, Porterville 504
Hours at 45 or below 45.
Sunrise: 7:08 Sunset: 4:47 pm. Hours of Daylight: 9:39
Yesterday’s Weather:
MAE : Madera 253 : DH1500 / 63 / 38 / 0.00 /
FAT : Fresno Airport 333 : DH1500 / 63 / 38 / 0.00 /
HJO : Hanford Airport 242 : DH1500 / 61 / 32 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 61 / 32 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 63 / 37 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 61 / 34 / 0.00 /
ATEC1 : Avenal 787 : DH1600 / M / 39 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 63 / 34 / 0.00 /
TFTC1 : Taft 759 : DH1556 / 61 / 34 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / M / 39 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr season % last year % Ave. 365 day ave.
STOCKTON 0.00 4.11 107 5.00 130 3.85 14.06
MODESTO 0.00 2.80 86 4.20 129 3.25 13.11
MERCED 0.00 4.56 163 3.56 127 2.80 12.50
MADERA 0.00 1.91 64 2.85 96 2.98 12.02
FRESNO 0.00 2.50 92 2.27 84 2.71 11.50
HANFORD 0.00 1.77 79 1.80 80 2.25 10.10
BAKERSFIELD 0.00 1.60 104 1.20 78 1.54 6.47
BISHOP 0.00 1.06 85 1.31 106 1.24 5.18
SALINAS 0.00 4.22 134 4.47 142 3.14 12.83
PASO ROBLES 0.00 4.73 169 3.52 126 2.80 12.78
SANTA MARIA 0.00 2.72 86 2.29 72 3.16 13.95
Next report: Saturday afternoon/December 21