December 19, 2017
Summary: Widespread upper 20s are again apparent throughout the citrus belts with a few locations in the mid 20s. lower 30s are more predominant in Kern County. A cold low pressure system is now off the coast of the Pacific Northwest and will enter northern California later this afternoon. It will spread light rain and snow over the northern part of the state. The associated cold front with this system will drive rapidly southward through central California Wednesday. It will bring gusty winds and at least a small chance of light showers, mainly north of Kern County. Precipitation is likely over the Sierra Nevada with lowering snow levels.
The flow behind this system is very cold and will drive down the valley Wednesday for colder temperatures with lowering dew points. This may drop temperatures Thursday morning well below freezing with isolated unprotected spots possibly in the 23 to 24 degree range. As upper level high pressure sets in late Thursday through Friday, the atmosphere will calm, setting the stage for low to mid 20s Friday and possibly Saturday.
A system will be diving into the Great Basin Saturday which could throw some cloud cover over the area, but at this point that is by no means guaranteed. Models are all over the place for the week between Christmas and New Year’s. If there’s any consensus at all, it is that a blocking ridge may set up over the west for another period of dry weather which could last through the period.
The two week outlook this morning is calling for near to marginally above average day time temperatures with possibly below average overnight lows.
Forecast: Mostly clear this morning. Becoming partly cloudy this afternoon. Mostly cloudy tonight and Wednesday with a small chance of light showers Wednesday, especially north of Kern County. Clearing Wednesday evening, becoming mostly clear overnight with the possible exception of portions of Kern County which could observe some upslope clouds into Thursday morning. Mostly clear Thursday afternoon through Friday. mostly clear to possibly occasionally partly cloudy Saturday through Tuesday.
Short Term:
| Madera 65/37/55/24/54 | Reedley 66/36/56/24/54 | Dinuba 65/36/56/23/55 | |
| Porterville 66/35/56/24/55 | Lindsay 66/35/57/23/55 | Delano 67/37/57/25/55 | |
| Bakersfield 67/39/57/29/55 | Arvin 67/37/56/25/56 | Taft 67/42/57/28/56 | |
| Lamont 68/39/57/27/56 | Pixley 66/37/57/25/55 | Tulare 65/36/56/24/54 | |
| Woodlake 66/36/57/24/56 | Hanford 66/35/56/25/56 | Orosi 65/35/56/23/54 | |
Seven Day Forecast:
| Friday
Mostly clear 23/56 |
Saturday
Partly cloudy 25/56 |
Sunday
Partly cloudy 26/61 |
Christmas Day
Partly cloudy 28/65 |
Tuesday
Partly cloudy 33/61 |
Two Week Outlook: December 26 through January 1: Models for this time frame are somewhat inconclusive. They do call for below average precipitation with temperatures close to seasonal values, this would be highs in the mid 50s and lows in the upper 20s to the mid 30s. The chance of precipitation remains low.
December: This model is indicating a better than even chance of above average temperatures for central and southern California all the way to the southeast with near to below average temperatures in the Pacific Northwest. As far as precipitation is concerned, this model does show better than average precip over Washington and Oregon and near average rainfall over central and northern California.
December, January, February: If this model is to be believed, winter this year will experience somewhat above average temperatures from California, stretching eastward and southward. Below average temperatures would prevail from the northern Rockies through the Plains states. As far as California is concerned, precipitation would be near to marginally below average with temperatures marginally above average, but take all this with a grain of salt.
Winds: Winds will be generally less than 10 MPH today with periods of near calm conditions. Winds will be out of the northwest Wednesday at 10 to 20 MPH with local gusts to 35 MPH along the west side. Winds will diminish Wednesday night except for winds remaining in the 10 to 15 MPH range along the west side. Winds Thursday through Friday will be generally less than 15 MPH with periods of near calm conditions during the overnight hours.
Rain: A fast moving and rather moisture starved low pressure system will dive southward through central California Wednesday. There is a small chance of light showers, mainly north of Kern County, on Wednesday. Dry weather will return Wednesday night and will last through at least Christmas. If medium range models have a grip on the situation, dry weather will continue through New Year’s.
Frost: Lows this morning are ranging from 27 to 31 as of 6:00am. There is a spattering of locations in the mid 20s. In Kern County, most locations are ranging from 29 to 34. All locations will be above freezing tonight due to increasing cloud cover and the beginning of the mixing process.
Thursday through Saturday mornings look very cold as modified Arctic air slides southward along the eastern rim of a big ridge extending into western Canada. Thursday morning may turn out to be a mixed bag as wind conditions may play a big role in the final outcome. It’s also possible some upslope clouds could form along the north facing slopes of the Tehachapi Mountains. Wind conditions along the west side may be strong enough to modify the situation there. However mainly an eastern Fresno County, Eastern Tulare County, and portions of Kern County where it remains clear could see temperatures in the 22 to 25 degree range with readings in the 27 to 33 degree range where winds are a factor.
Friday and possibly Saturday will be the most dangerous in this episode. Widespread low to mid 20s are likely throughout the region with possibly long durations with the coldest unprotected low spots down to 20 to 22 or so.
Models do show occasional cloudiness Saturday through Christmas Day which may help out on those days. It will depend on coverage.
At any rate, potentially well below freezing readings will occur each night through at least Christmas Day with slow moderation beginning Christmas Eve.
Lows Tonight:
All locations will be above freezing.
AF=Above Freezing
Afternoon Dew Points Today: Low to mid 30s. Bakersfield, Upper 20s to the mid 30s.
Relative Humidity Forecast: Hanford, 35%/95% Bakersfield, 30%/75%
Actual Humidity December 17, 2017: Delano, NA, Porterville, 82%/20%
Percentage of Sunshine Today/Tomorrow: Visalia: Today 60% tomorrow 10%, Bakersfield: Today 70% tomorrow 10%.
ET Rates Over the Past Seven Days December 17, 2017: Stratford .44, Parlier .35, Blackwell, .53 Lindcove .38, Arvin .49, Orange Cove .42, Porterville .36, Delano .NA., Madera Two .36. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 49, Parlier 49, Blackwell 53, Lindcove, 54, Arvin, 52, Orange Cove 49, Porterville 50, Delano NA, Madera Two 51
Mean Temperatures for December. Month So Far: 47.0 +1.9
Record Temperatures: 71/26. Average Temperatures: 54/35
Heating Degree Days this Season: 606, -229 Courtesy of the NWS
Precipitation: Seasonal total/average/above or below average:
Since December 17, 2017 Fresno: .37 season. or -2.16. Month to Date: T
Since December 17, 2017, Bakersfield: .03, or -1.41, Month to Date: ..00
Water year season is from October 1st through September.
Chilling ours November 1st through February 28: Orange Cove, 317, Parlier, 336, Arvin, 271, Shafter, 382, Stratford, 336, Madera two, 486, Alpaugh, NA, Delano, NA, Lindcove, 313, Porterville, 466. Hours at 45 or below 45.
Sunrise: 7:07 am Sunset: 4:46 pm. Hours of Daylight: 9:38
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 64 / 32 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 64 / 34 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 65 / 29 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 67 / 35 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 65 / 31 / 0.00 /
ATEC1 : Avenal 787 : DH1548 / 66 / 33 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 66 / 30 / 0.00 /
TFTC1 : Taft 759 : DH1553 / 68 / 31 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 63 / 33 / 0.00 /
Rainfall: Season % Last y. % Ave. Annual Ave.
STOCKTON 0.00 0.91 25 5.46 148 3.70 14.06
MODESTO 0.00 0.98 32 4.30 138 3.11 13.11
MERCED 0.00 1.03 38 3.72 139 2.68 12.50
MADERA 0.00 0.32 11 3.62 127 2.85 12.02
FRESNO 0.00 0.37 14 4.08 158 2.59 11.50
HANFORD 0.00 0.37 18 2.00 95 2.11 10.10
BAKERSFIELD 0.00 0.03 2 1.02 69 1.47 6.47
BISHOP 0.00 0.16 13 0.15 13 1.19 5.18
SALINAS 0.00 0.75 25 3.82 127 3.01 12.83
PASO ROBLES 0.00 0.25 9 3.40 128 2.66 12.78
SANTA MARIA 0.00 0.09 3 4.02 133 3.02 13.95
Next Report: Tuesday, December 19/pm