November 27, 2018
Summary: Fog is not nearly as widespread this morning due to varying amounts of high clouds that moved through during the course of the night. A cold front is now spreading rain and snow over northern California. Precipitation will spread into parts of central California later this afternoon and tonight, though amounts should be quite light. South of Fresno County, some locations may remain dry as the thrust of this storm is more eastward than southeastward.
Let the games begin for Wednesday through Thursday night as an impressive low, both at the surface and aloft, will be centered just northwest of San Francisco by Thursday morning. Models show a slug of subtropical moisture feeding in to the southern flank of the low then riding inland through central California later Wednesday night and Thursday for the potential of significant amounts of rain on the valley floor and just plain heavy precip up and down the Sierra Nevada and, to a lesser extent, the Kern County mountains. Rainfall amounts of two to three inches could easily accumulate over the foothills with .50 to 1.00 totals not out of the question on the valley floor.
The other challenge with this system will be wind. The surface charts still show plenty of isobars, meaning lines of equal pressure between off shore northern California and southern California. Strong winds will develop over the Kern County mountains and they may make it down to the valley floor late Wednesday night and Thursday. If they do move all the way down the hill, 50 plus MPH winds are possible near the base of the Grapevine and locally elsewhere. Gusty south to southeast winds are also anticipated over the rest of the valley, but generally in the 15 to 30 MPH range.
As the low begins to slip eastward, winds will die off quickly Wednesday night.
Over the weekend is when the next area of low pressure will arrive. This storm will have its origins in the Gulf of Alaska, so when it arrives during the day Saturday, expect snow levels to lower down to 3,000 to 4,000 feet as the colder air mass moves in. models are indicating a brief northerly flow as the trough enters the interior west, leading to some possible frost concerns beginning Monday morning. More on that in the frost discussion below.
Monday through Thursday of next week now look dry as a relatively weak high pressure system at the mid and upper levels of the atmosphere takes over for a few days. As a warm air inversion develops and a wet valley floor is apparent, fog and /or low clouds will have no problem developing. Temperatures will be below average next week as we remain between a low to our east and upper level high pressure just off shore. Models do point to active weather beginning about the sixth or seventh, but that forecast will likely change and flip flop back and forth as the days go by.
Forecast: Increasing cloudiness today. Showers spreading down to Fresno County later this afternoon with a small chance of light showers south of Fresno County. Showers from Fresno County north tonight with a small chance further south. A chance of showers Wednesday morning. Rain becoming likely later Wednesday afternoon and night, heavy at times. Rain Thursday, locally heavy at times, possibly accompanied by strong, gusty winds, especially in Kern County. Showers Thursday night. Mostly cloudy Friday with lingering showers, mainly in the foothills and mountains. Increasing cloudiness again Friday night with periods of showers becoming likely, especially Saturday afternoon and night. A chance of showers Sunday, mainly during the morning, becoming partly to mostly cloudy Sunday night and Monday morning. Mostly clear Monday afternoon through Tuesday with areas of night and morning fog and low clouds.
Short Term:
Madera 67/49/58/50/58 | Reedley 67/50/60/51/58 | Dinuba 66/48/59/49/58 | |
Porterville 68/49/60/51/60 | Lindsay 67/48/59/51/59 | Delano 68/50/60/51/59 | |
Bakersfield 70/51/65/53/60 | Taft 69/52/66/52/61 | Arvin 70/50/65/52/62 | |
Lamont 69/51/66/52/60 | Pixley 68/49/60/50/60 | Tulare 67/48/60/48/58 | |
Woodlake 67/48/59/51/59 | Hanford 68/50/60/51/58 | Orosi 67/48/59/49/58 |
Seven Day Forecast:
Friday
AM showers possible 48/58 |
Saturday
Showers likely 44/54 |
Sunday
AM Showers possible 40/53 |
Monday
AM fog/partly cloudy 45/54 |
Tuesday
AM fog/PM sun 32/55 |
Two Week Outlook: December 4 through December 10: This model shows a possible wide area of low pressure over the interior west with possibly a northwest flow into California. This would bring marginally below average temperatures. Precipitation during this time frame appears to be marginally likely.
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 light to near calm this morning. This afternoon, winds will be out of the southeast at 5 to 10 MPH with locally stronger gusts, mainly from Fresno County north. Winds Wednesday will be out of the southeast at 10 to 15 MPH with stronger gusts. Winds late Wednesday night and Thursday will be gusty in areas out of the south to southeast at 15 to 30 MPH with stronger gusts, mainly along the west side but locally elsewhere. It’s possible we could see some strong, gusty winds blowing downslope off the mountains Thursday, possibly making it out over the valley floor. If this occurs, wind gusts exceeding 50 MPH are possible near the base of the Tehachapi Mountains, especially below the passes. These winds will quickly die off Wednesday night. Winds Friday will continue to be mainly out of the southeast at 10 to 15 MPH with stronger gusts.
Rain: Rain is already spreading over northern California as a cold front and its associated low pressure system moves onshore. Light rain should reach Fresno County this afternoon with a small chance of light showers further south. Light rain from Fresno northward will continue tonight with a small chance further south. A deep low both at the surface and aloft will begin to make its move on central California Wednesday. Short term models are quite interesting for later Wednesday into Thursday as they are picking up on a slug of subtropical moisture riding on the jet stream and moving into central California Wednesday. This will further increase the chance for heavy rain over the mountains and locally over the valley floor as well. The trough will begin to slide inland by Thursday evening as the rain tapers off into showers.
Rainfall amounts in this event, I still believe, will be between .50 and 1.00 north of Kern County and east of Highway 99. In western Fresno County and over Kings County, half inch totals would not be a surprise. Even in Kern County, .33 to .50 cannot be ruled out. That could be greatly reduced if strong winds develop and blow downslope off the Tehachapi Mountains. This is entirely possible.
Light showers will linger Friday, mainly over the mountain areas, ending by Friday evening. The next Pacific storm is much colder with its origins in the Gulf of Alaska. It will arrive Saturday and Saturday night with widespread shower activity and snow down to 3,000 feet in the mountains. This system will not carry nearly as much water, but nevertheless I wouldn’t be surprised to see totals of .25 in some areas. Showers will taper off Sunday morning with dry weather likely Monday through Thursday of next week.
Frost Discussion: It appears we could see frost challenges beginning Monday morning. A cold low will drop out of the Gulf of Alaska and into California Saturday into Sunday morning with snow levels dropping to 3,000 to 4,000 feet. Models show a wide area of cold low pressure over the interior west Monday and Tuesday with a big off shore high stretching into northern Canada. Cold air riding southward will allow temperatures to fall to below average next week. For now, this does not look like a freeze event, but I wouldn’t be surprised to see upper 20s and lower 30s as early as Monday morning with a higher risk factor thereafter. It’s also possible that with plenty of moisture on the valley floor, fog and low clouds could become widespread as the week wears on. Fog and low clouds, of course, are a great protector to citrus, and could serve that role from Tuesday on.
Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: Mid to upper 40s.
Afternoon Dew Points Today: Low to mid 50s. Kern: Mid to upper 40s.
Humidity: Porterville: 65%/95%, Bakersfield: 40%/85%
Actual Humidity November 26, 2018: Delano, 100%/65%, Porterville, 98%/57%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 40% tomorrow 10% Bakersfield: Today: 50% Tomorrow: 20%
ET Rates Over the Past Seven Days: Stratford .43, Parlier .35, Blackwell .48, Lindcove .38, Arvin .44, Orange Cove .41, Porterville .36, Delano .37 Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 58, Parlier 57, Blackwell 62, Lindcove, 60, Arvin, 56, Orange Cove 56, Porterville 58, Delano 56
Record Temperatures: 78/27. Average Temperatures: 60/36
Heating Degree Days this Season: 285 -142
Courtesy of the NWS
Average temperature for November so far: 55.0 +2.3
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: .60 season. or -0.95 Month to Date: .50 -.42
Since Oct 1, 2018, Bakersfield: .34, or -.50. Month to Date: .34 -.20
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, 144, Parlier, 188 , Arvin, 124 Shafter, 186 Stratford, 162, Delano 169, Lindcove, 152, Porterville, 231
. Hours at 45 or below 45.
Sunrise: 6:50 am Sunset: 4:43 pm. Hours of Daylight: 9:54
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 70 / 47 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 67 / 47 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 67 / 41 / 0.00 /
NLC : Lemoore Naval AS 234 : DHM / M / M / M /
BFL : Bakersfield Airport 496 : DH1600 / 69 / 47 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 66 / 46 / 0.00 /
ATEC1 : Avenal 787 : DH1553 / 70 / 45 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 68 / 42 / 0.00 /
TFTC1 : Taft 759 : DH1553 / 64 / 49 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 66 / 44 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr Season % L.Y. % Ave. Ave. yearly total
STOCKTON 0.00 2.51 111 0.80 35 2.27 14.06
MODESTO 0.00 0.81 44 0.79 43 1.83 13.11
MERCED 0.00 0.58 31 0.86 46 1.86 12.50
MADERA 0.00 0.58 30 0.29 15 1.91 12.02
FRESNO 0.00 0.60 39 0.32 21 1.55 11.50
HANFORD 0.00 0.34 24 0.17 12 1.42 10.10
BAKERSFIELD 0.00 0.34 40 0.03 4 0.84 6.47
BISHOP 0.00 0.41 55 0.16 21 0.75 5.18
SALINAS 0.00 1.83 105 0.41 23 1.75 12.83
PASO ROBLES 0.00 0.42 28 0.24 16 1.50 12.78
SANTA MARIA 0.00 0.57 33 0.07 4 1.73 13.95
Next report: Tuesday, November 27/pm