December 8, 2021
It is another typical December morning out there this morning. Porterville, Visalia, Fresno, and Madera are reporting a visibility of ¼ mile or less. For today, we will be under a weak ridge of high pressure which will quickly give way to a trough of low pressure diving southeastward from off the coast of the Pacific Northwest. Precipitation estimates for the valley range from roughly 1/3 to 6/10 of an inch north of Kern County. More on this in the rain discussion below. This is a relatively cold system so the snow level will drop down to 4,000 to 5,000 feet by Thursday morning.
The air mass behind this system is cold, but nothing unusual for this time in December. Residual and upslope clouds will keep most areas above freezing Friday morning, however widespread upper 20s and lower 30s will be the rule Saturday morning.
Upper level high pressure will govern the pattern for most of the weekend, but will begin to give way late Sunday as a powerful winter storm drops out of the Gulf of Alaska to a position off the coast of the Pacific Northwest and northern California. The jet stream will flank south/southwest to north/northeast underneath the low into central and southern California. The coast range and the Sierra Nevada will pick up plenty of precipitation due to the lifting motion of the jet stream. Rainfall amounts from this storm will likely be all over the place due to rain shadows which are typical in strong winter storms.
Medium range models continue to show an active weather pattern for at least the next week and a half or so.
Forecast: Areas of low clouds and fog this morning. Partly cloudy this afternoon. Increasing cloudiness tonight with rain becoming likely from Fresno County north after midnight. Periods of rain Thursday morning with a chance of showers Thursday afternoon. Mostly to partly cloudy Thursday night and Friday. Areas of low clouds and fog Friday night into Saturday morning. Mostly clear Saturday afternoon with areas of night and morning fog and low clouds. Increasing cloudiness Sunday night leading to an increasing chance of rain Monday. Rain at times Monday night through Tuesday night with gusty winds at times. A chance of lingering showers Wednesday morning, otherwise it will be partly cloudy.
|Madera 59/42/54/39/52||Reedley 60/43/54/37/53||Dinuba 58/41/54/37/52|
|Porterville 62/42/54/36/53||Lindsay 61/40/54/36/53||Delano 61/43/54/38/52|
|Bakersfield 63/48/51/42/52||Taft 61/49/51/46/52||Arvin 62/44/51/44/53|
|Lamont 61/45/53/40/54||Pixley 59/44/54/36/53||Tulare 60/42/54/36/52|
|Woodlake 60/41/54/36/52||Hanford 59/44/54/37/53||Orosi 59/41/54/35/51|
Seven Day Forecast:
Patchy fog/partly cloudy
AM fog/increasing clouds
Two Week Outlook: December 15 through December 21: This model is not quite as aggressive in projecting precipitation potential for central California. It does show a colder pattern with a chance of precipitation during this time frame and with below average temperatures.
December, January, February: If this model is to be believed at all, temperatures will be marginally above average over central California. This model also depicts the main storm track continuing into the Pacific Northwest with somewhat below average precipitation over the southern 2/3 of California.
Wind Discussion: Winds today will be light and variable. Winds tonight will be out of the southeast to east at 8 to 15 MPH then will be out of the northwest at 8 to 15 MPH with stronger gusts Thursday through Thursday evening. Winds later Thursday night through Saturday will be generally variable in nature and generally less than 10 MPH with periods of near calm conditions
Rain: The chance of rain will begin to pick up after midnight tonight from Fresno County north then will spread over the remainder of the valley during the early morning hours. Rain can be expected at times Thursday morning, tapering off to a chance of showers Thursday afternoon with dry conditions Thursday night through Sunday. It still appears rainfall amounts north of Kern County will be somewhere in the 1/3 to ½ inch range with locally more. Due to the rain shadow affect along the coast range, around ¼ to 1/3 of an inch seems plausible along the west side. About ¼ to 1/3 of an inch is possible in the valley portion of Kern County. Dry conditions will return Thursday night through Sunday. As each set of model information comes across the desk, it’s becoming more obvious that a powerful winter storm will be off the coast of the Pacific Northwest and northern California Sunday and Monday. A moist feed of air will be driven into central California for potentially heavy precipitation along the Sierra Nevada. Typically these strong winter storms cause rain shadows along the west side and in Kern County. I’ll have better information in the coming days.
Frost: All locations will be above freezing tonight. There is a chance of lower 30s in some locations, mainly from Fresno County northward Friday morning. However, upslope clouds and mixing should keep most areas above freezing. By Saturday morning, the atmosphere will have settled down. This air mass will be cold enough for upper 20s and lower 30s on a widespread basis Sunday morning. A few river bottom type locations could drop into the lower 20s for short durations. It’s also quite possible that a low cloud deck will develop, banking up against the north facing slopes of the Kern County mountains and the west facing slopes of the Sierra Nevada. If this occurs, then most locations will remain in the 30s.
Longer term, it’s possible we may see some more frost nights after Wednesday of next week as we dry out for a bit. However, the 6 to 10 and two week models show below average temperatures. Keep in mind, it won’t be long before we enter the riskiest time in the citrus frost season, but for nor there’s nothing suggesting a critically cold air mass.
tual Humidity Range Yesterday: Delano, 99%/67% Porterville, 100%/68%. Dew points: Mid to upper 40s. Kern: Mid to upper 40s.
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 20%, tomorrow 10%. Bakersfield: Today: 40%/. Tomorrow, 10%.
ET Rates Over the Past Seven Days:. Stratford .26, Parlier .26, Arvin .40, Orange Cove .28, Porterville .26, Delano .25. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford, 57, Parlier 55, Arvin, .56, Orange Cove 56, Porterville 53, Delano 48. *=data missing.
Average Temperatures: 56/37. Record Temperatures: 77/25
Heating Degree Days This Season. 501 -63. Varies widely from location to location. courtesy of the NWS
courtesy of the NWS
Precipitation: Seasonal total for Fresno, .1.57 or -.17. Monthly .00. -.31
Precipitation for Bakersfield, Season, .95 or -.03. Month to date .T -.19
Average Temperature this month: 50.0, +.2.7 Taken NWS Hanford.
Water year season is from October 1st through September 30.
Chilling Hours November 1st through February 28: Orange Cove, 123, Parlier, 168 , Arvin, 167, Belridge, 178 ,Shafter, 168 , Stratford, 193 , Delano, 169 , Porterville, 203 `
Sunrise. 7:00, Sunset, 4:43, hours of daylight, 9:43
MCE : Merced AP 153 : 53 / 41 / 0.00 /
MAE : Madera AP 253 : 55 / 36 / T /
FAT : Fresno AP 333 : 54 / 40 / 0.00 /
HJO : Hanford AP 242 : 53 / 36 / 0.00 /
NLC : Lemoore NAS 234 : 54 / 37 / 0.00 /
BFL : Bakersfield AP 496 : 59 / 40 / 0.00 /
VIS : Visalia AP 292 : 51 / 36 / T /
PTV : Porterville AP 442 : 58 / 36 / 0.00 /
Rainfall: 24hr season % L.Y. % Ave. Annual total ave
STOCKTON 0.02 4.37 169 0.09 3 2.59 13.45
MODESTO 0.07 3.14 152 0.10 5 2.06 12.27
MERCED 0.01 2.00 99 1.08 53 2.02 11.80
MADERA T 0.65 38 0.16 9 1.71 10.79
FRESNO 0.00 1.57 90 0.28 16 1.74 10.99
HANFORD 0.00 1.24 95 0.13 10 1.31 8.13
BAKERSFIELD T 0.95 97 0.39 40 0.98 6.36
BISHOP T 0.78 103 T 0 0.76 4.84
SALINAS 0.07 2.26 98 0.37 16 2.30 12.58
PASO ROBLES M M M M M M 12.15
SANTA MARIA 0.01 1.41 70 0.25 12 2.02 13.32
Next report: December 8 PM