September 8, 2018
Summary: Strong upper level high pressure is centered just off the south central California coast this morning. The freezing level has risen all the way up to 17,000 feet which is one of the few times during the summer season it has risen that high. The marine layer is only at 1,000 feet, so no influence from that source, yet. A low pressure system will develop off the coast of British Columbia this weekend and will be centered off the Washington coast by Monday. It will eventually develop a weak trough down into northern California. This will effectively lower pressures aloft and will also begin to generate an on shore flow, allowing the marine layer to rise in depth and flow down the valley, especially once we get to mid week and beyond.
This low center over the Pacific Northwest shows up on models for about a week or so, creating a dry southwesterly flow. With occasional bursts of marine air moving inland, temperatures will lower to near seasonal values and possibly even a bit below. This is a very dry pattern, keeping the monsoon to the south and east of our region.
One model this morning was quite interesting, however, it shows a hurricane working its way to a position southwest of Cabo San Lucas by next Friday. It then is projected to weaken rapidly, but will be centered near the Baja coast Sunday and Monday. On paper, this would give a chance of showers over southern California from roughly the Antelope Valley southward. This is a tropical event that may not even occur, but it’s the first time this season I’ve seen anything move this far north. For now, we’ll take this with a grain of salt until some semblance of uniformity takes place on models.
Forecast: Mostly clear skies through Tuesday. Mostly clear Tuesday night through Saturday.
Short Term:
| Madera 101/60/97/58/96 | Reedley 100/59/97/58/95 | Dinuba 99/57/95/56/95 | |
| Porterville 100/60/97/58/96 | Lindsay 100/59/96/58/96 | Delano 101/64/97/61/97 | |
| Bakersfield 100/71/97/68/96 | Arvin 101/66/97/64/95 | Taft 99/71/97/69/96 | |
| Lamont 101/65/97/64/97 | Pixley 100/61/96/59/95 | Tulare 99/59/95/57/95 | |
| Woodlake 100/60/96/58/95 | Hanford 101/60/97/58/95 | Orosi 100/59/96/57/95 | |
Seven Day Forecast:
| Tuesday
Mostly clear 57/94 |
Wednesday
Mostly clear 57/91 |
Thursday
Mostly clear 56/90 |
Friday
Mostly clear 58/92 |
Saturday
Mostly clear 60/93 |
Two Week Outlook: September 14 through September 20: For a change, strong upper level high pressure which has been so persistent this summer is nowhere to be found on this model. Instead, a trough of low pressure over the Pacific Northwest and northern California is the main player. Temperatures under this regime will average near to possibly blow average levels with dry conditions continuing.
September: This model indicates there will be a higher than active monsoon over the Desert Southwest and possibly central and southern California. This typically does not affect the valley floor other than cloud cover, but could result in a larger number of days of thunderstorms over the Sierra Nevada and possibly even the Kern County mountains. With generally high pressure over the southwest, temperatures will likely be somewhat above seasonal average.
September, October, November: The first part of this time frame will see a more active than usual monsoon in place for above average rain over the Sierra Nevada and possibly the mountains and deserts of southern California. October and November’s conditions aren’t as easy to determine. At this time we’ll call for generally average values for both rain and temperatures.
Winds: Winds will be mainly out of the west to northwest at 5 to 12 MPH at times through Tuesday with stronger gusts possible.
Rain: Expect dry conditions indefinitely.
Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: Mid to upper 40s.
Humidity: Visalia: 20%/70% Bakersfield: 15%/50%
Actual Humidity September 7, 2018: Delano, 91%/23%, Porterville, 82%/20%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 100% tomorrow 100% Bakersfield: Today: 100% Tomorrow: 100%
ET Rates Over the Past Seven Days: Stratford 1.67, Parlier 1.54, Blackwell 1.78, Lindcove 1.51, Arvin 1.76, Orange Cove 1.75, Porterville 1.43, Delano 1.55, Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 73, Parlier 78, Blackwell 85, Lindcove, 77, Arvin, NA, Orange Cove 78, Porterville 84, Delano 77,
Record Temperatures: 108/49. Average Temperatures: 93/61
Cooling Degree Days this Season: 1845 +438
Courtesy of the NWS
Average temperature for September so far: 79.6 +3.6
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2017 Fresno: 6.73 season. or -4.61. Month to Date: .00
Since Oct 1, 2017, Bakersfield: 3.93, or -2.45. Month to Date: .00
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, Parlier, Arvin, Shafter, Stratford, Madera two, Lindcove, Porterville, Hours at 45 or below 45.
Sunrise: 6:36 am Sunset: 7:15 pm. Hours of Daylight: 12:42
Yesterday’s Weather:
MAE : Madera 253 : DH1700 / 102 / 62 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 100 / 69 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 99 / 61 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 100 / 62 / 0.00 /
BFL : Bakersfield Airport 496 : DH1700 / 98 / 73 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 96 / 62 / 0.00 /
ATEC1 : Avenal 787 : DH1656 / 98 / 64 / 0.00 /
PTV : Porterville Airport 442 : DH1700 / 97 / 65 / 0.00 /
TFTC1 : Taft 759 : DH1652 / 98 / 76 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 98 / 61 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
Year % Last Y. % Ave. Annual ave.
STOCKTON 0.00 9.22 67 21.79 158 13.79 14.06
MODESTO 0.00 8.17 64 16.93 132 12.86 13.11
MERCED 0.00 7.06 58 16.03 131 12.23 12.50
MADERA 0.00 7.22 61 14.18 120 11.79 12.02
FRESNO 0.00 6.73 59 17.20 152 11.34 11.50
HANFORD 0.00 4.70 47 11.05 111 9.94 10.10
BAKERSFIELD 0.00 3.95 62 7.83 122 6.40 6.47
BISHOP 0.00 3.08 62 9.18 184 5.00 5.18
SALINAS 0.00 7.16 57 16.45 130 12.67 12.83
PASO ROBLES 0.00 9.62 77 16.16 129 12.57 12.78
SANTA MARIA 0.00 6.01 43 18.69 135 13.82 13.95
Next report: Monday, September 10