November 15, 2017
Summary: A year ago, we heard the term “atmospheric river of air” which resulted in heavy precipitation for northern and central California. The first AR of the season is now underway in northern California as a wide swath of mid Pacific air is feeding underneath a low off the coast of the Pacific Northwest and is slamming into northern California with heavy amounts of precip. Rain has progressed as far south as Monterey along the coast and Yosemite in the Sierra Nevada. This is the type of situation where the jet stream will be lifted by the Sierra Nevada, causing strong rain shadows along the west side and in Kern County with copious amounts of precipitation along the Sierra Nevada north of Kern County. In fact, anywhere from 3 to 4 inches of rain in the foothills is possible in the Yosemite area from today through Friday and possibly 2 to 3 inches as far south as Tulare County. Rainfall in the valley is discussed below in the rainfall section.
The frontal band itself and the associated jet stream will sag very slowly south over the next 36 hours. It’s doubtful any precipitation will reach as far south as Fresno County until possibly late tonight or even Thursday morning. It may be late Thursday night or even Friday morning before the front reaches Kern County before precipitation ends by midday Friday in all areas with the exception of the higher elevations of the Sierra Nevada.
Dry and cooler weather will move in behind the front for the weekend. Interestingly enough, the models encompassing Sunday night through Tuesday are indicating another AR will develop, running from southwest to northeast into northern California for another bout of possibly heavy rain. Models have been consistent, however, in keeping any precipitation north of roughly a Monterey/Yosemite line so we’ll follow suit and go with a dry forecast for now for early next week.
Models for the remainder of next week are so far pointing to dry conditions with the storm track remaining farther north. We’ll see if changes need to be made in the longer term forecast as modeling information comes our way.
Forecast: Mostly cloudy today and tonight with a slight chance of rain as far south as Fresno County by late tonight. Periods of rain slowly creeping down the valley Thursday and Thursday night, but not reaching Kern County until late Thursday night or perhaps even Friday morning. Partly to mostly cloudy Friday afternoon through Saturday morning. Mostly clear to occasionally partly cloudy Saturday afternoon through Sunday. Variable cloudiness at times Sunday night through Tuesday. Mostly clear to occasionally partly cloudy Tuesday night and Wednesday.
Short Term:
Madera 70/52/68/46/63 | Reedley 71/51/70/46/62 | Dinuba 72/53/70/47/63 | |
Porterville 73/53/72/47/62 | Lindsay 73/52/70/46/63 | Delano 74/53/72/50/64 | |
Bakersfield 75/54/76/52/65 | Arvin 76/56/75/54/62 | Taft 74/57/75/55/64 | |
Lamont 76/56/75/53/63 | Pixley 73/52/70/47/63 | Tulare 70/52/70/46/62 | |
Woodlake 72/54/70/46/62 | Hanford 72/53/70/46/62 | Orosi 72/54/70/47/62 |
Seven Day Forecast:
Saturday
Partly cloudy 40/62 |
Sunday
Partly cloudy 36/64 |
Monday
Variable clouds 44/70 |
Tuesday
Variable clouds 53/71 |
Wednesday
Partly cloudy 50/70 |
Two Week Outlook: November 22 through November 28: This model is indicating the storm track will migrate somewhat further south during this time frame. Therefore, the risk of rain will be greater, especially after Thanksgiving. The dominant flow in the upper atmosphere will remain out of the west or southwest, so above average temperatures will continue.
November: November is when the traditional rainfall season begins. For now, it appears this month will be drier than average as upper level high pressure is depicted as more dominant over the Desert Southwest through southern California. This would keep the storm track, for the most part, north of our region, and would also, on the average, result in above average temperatures.
November, December, January: It appears this model is leaning towards above average precipitation perhaps over the Pacific Northwest and the northern Rockies. Higher than average pressure will continue over the Desert Southwest to the southern Midwest. There is really no strong signature for above or below precipitation, but temperatures during the winter months should be at least marginally above average.
Winds: Winds will be out of the southeast later today at 5 to 15 MPH with stronger gusts, mainly north of Fresno County and along the west side. Winds later tonight through Thursday night will be mainly out of the southeast at 10 to 15 MPH with local gusts to 25 MPH from Fresno County north and along the west side. Winds Friday will be out of the northwest at 5 to 15 MPH with stronger gusts, diminishing Friday night with light winds Saturday.
Rain: The timing of the onset of precipitation with this event will be tricky to call due to the very slow southward progression of the jet stream and the cold front. It’s possible rain could reach as far south as Fresno County late tonight or possibly early Thursday then it will just inch southward, possibly reaching Kern County late Thursday or even possibly Friday morning. The precipitation potential is reasonably good along the east side of the valley, especially near the foothills. This is a classic storm for rain shadows as downsloping off the coast range and upsloping along the Sierra Nevada really do interesting things to a system. From roughly Porterville northward, a quarter to a half inch is possible with this event with locally more in Fresno and Madera Counties. Along the west side, anywhere from a few hundredths to perhaps a tenth or two is possible with possibly less than a tenth of an inch over the valley portion of Kern County.
Dry weather will return Friday afternoon and continue probably well into next week. Another AR event is possible for northern California from Sunday night through Tuesday for heavy rain there, but so far projections keep the precip north of about a Monterey/Merced line. The storm track is nudged further north once we get past Tuesday.
Afternoon Dew Points Today: Mid to upper 40s. Bakersfield, mid to upper 40s.
Relative Humidity Forecast: Hanford, 45%/90% Bakersfield, 45%/75%
Actual Humidity November 13, 2017: Delano, NA, Porterville, 98%/45%
Percentage of Sunshine Today/Tomorrow: Visalia: Today 10% tomorrow 0%, Bakersfield: Today 20% tomorrow 20%.
ET Rates Over the Past Seven Days November 13, 2017: Stratford .61, Parlier .51, Blackwell .56, Lindcove .54, Arvin .58, Orange Cove .59, Porterville .46, Delano .NA., Madera Two .51. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 60, Parlier 62, Blackwell 64, Lindcove, 63, Arvin, 65, Orange Cove 60, Porterville 63, Delano 64, Madera Two 63
Mean Temperatures for November Month So Far: 57.6 +2.4
Record Temperatures: 79/30. Average Temperatures: 66/42
Heating Degree Days this Season: 174, -60 Courtesy of the NWS
Precipitation: Seasonal total/average/above or below average:
Since November 13, 2017 Fresno: .10 season. or -.97. Month to Date: .01
Since November 13, 2017, Bakersfield: .02, or -.53, Month to Date: ..02
Water year season is from October 1st through September.
Chilling ours November 1st through February 28: Orange Cove, 33, Parlier, 42, Arvin, 11, Shafter, 32, Stratford, 39, Madera two, 88, Alpaugh, 11, Delano, NA, Lindcove, 28, Porterville, 63. Hours at 45 or below 45.
Sunrise: 6:37 am Sunset: 4:49 pm. Hours of Daylight: 10:13
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 71 / 47 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 67 / 48 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 69 / 45 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / M / M / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 70 / 49 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 68 / 45 / 0.00 /
ATEC1 : Avenal 787 : DH1525 / 68 / 48 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 70 / 44 / 0.00 /
TFTC1 : Taft 759 : DH1554 / 68 / 54 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 68 / 48 / 0.00 /
Rainfall:
STOCKTON 0.02 0.24 15 2.40 154 1.56 14.06
MODESTO 0.01 0.26 21 2.05 164 1.25 13.11
MERCED 0.00 0.17 12 1.45 103 1.41 12.50
MADERA 0.00 0.08 5 0.62 42 1.46 12.02
FRESNO 0.00 0.10 9 0.67 60 1.11 11.50
HANFORD 0.00 0.06 6 0.65 60 1.08 10.10
BAKERSFIELD 0.00 0.02 4 0.24 42 0.57 6.47
BISHOP 0.00 0.00 0 0.09 17 0.52 5.18
SALINAS T 0.32 29 1.69 151 1.12 12.83
PASO ROBLES 0.00 0.21 19 1.39 128 1.09 12.78
SANTA MARIA 0.00 0.04 3 1.28 110 1.16 13.95
Next Report: Wednesday, November 15/pm