September 24, 2018
Summary: A trough of low pressure is currently moving eastward to the northern Rockies and is extending southward into northern Nevada and Utah. This system did very little to lower temperatures as even the marine layer only deepened to around 1,500 feet overnight. Still, pressures are slightly lower aloft which should allow temperatures to back off just a tad, perhaps into the lower 90s.
That will be short lived, however, as strong upper level high pressure will build northward along the west coast. Temperatures by Wednesday could be pushing the century mark in the hottest locations in the valley with widespread upper 90s elsewhere. The high will maintain its position through the workweek as a low center develops well off the northern and central coast. This low could be just what we need for a significant cooling trend over the weekend. Most of the model information indicates the low will move slowly through the northern half of California, especially Saturday night and Sunday. So far, models for central California point to dry weather with temperatures lowering into the 80s. one model even suggests upper 70s in some areas, especially Sunday.
It’s the medium term models that have piqued my interest. A new low center will develop off the central coast early next week and will approach the coast about next Wednesday. In the meantime, some, but certainly not all of, the models are indicating a dying tropical system will move to a position just southwest of San Diego by next Wednesday. It would feed a great deal of moisture into southeastern California and Arizona. With the other low just off the central coast, it is possible some of this moisture could be drawn into central California in about 9 or 10 days. This piques my interest more than usual as it’s the third model run in a row that has pointed in that direction. We’ll keep you posted.
Forecast: Mostly clear skies through Thursday. Mostly clear skies will continue Thursday night through Tuesday.
Short Term:
| Madera 92/55/94/57/97 | Reedley 92/55/95/57/96 | Dinuba 91/54/94/57/95 | |
| Porterville 92/54/95/57/98 | Lindsay 93/55/95/56/98 | Delano 92/58/95/60/97 | |
| Bakersfield 93/65/94/67/98 | Arvin 94/61/96/63/98 | Taft 92/66/94/68/97 | |
| Lamont 93/61/95/64/98 | Pixley 92/55/95/56/96 | Tulare 91/54/94/56/95` | |
| Woodlake 91/55/94/58/96 | Hanford 93/56/95/58/98 | Orosi 92/55/94/57/97 | |
Seven Day Forecast:
| Thursday
Mostly clear 61/98 |
Friday
Mostly clear 62/94 |
Saturday
Mostly clear 57/86 |
Sunday
Mostly clear 53/81 |
Monday
Mostly clear 51/85 |
Two Week Outlook: October 1 through October 7: Models are actually quite interesting for this time period. A significant area of low pressure will be off the west coast. Some models are suggesting a chance of showers. About a week from Wednesday, some models are showing a tropical system becoming involved, in which case rain would be likely. For now, that’s in the very low chance category. Temperatures should be near to marginally below average.
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 less than 12 MPH through Tuesday.
Rain: Expect dry weather through at least Tuesday of next week and possibly longer. Around Wednesday of next week is where the weather pattern becomes more interesting. A fairly significant low is projected to be off the coast. This, in and of itself, could spawn a few showers over the valley floor. Adding a little intrigue is the possibility of a dying tropical system moving to a position just southwest of San Diego by Thursday. For now, models show this moisture going into southern California and Arizona, but with that low just off the central coast, there could be tropical moisture moving into central California. At this point, we’ll put that in the very low chance category, but it’s certainly a pattern worth monitoring.
Afternoon Dew Points Today: Mid to upper 40s. Kern: Low to mid 40s.
Humidity: Visalia: 20%/70% Bakersfield: 15%/45%
Actual Humidity September 23, 2018: Delano, 93%/20%, Porterville, 76%/17%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 80% tomorrow 90% Bakersfield: Today: 80% Tomorrow: 90%
ET Rates Over the Past Seven Days: Stratford 1.48, Parlier 1.32, Blackwell 1.45, Lindcove 1.31, Arvin 1.51, Orange Cove 1.46, Porterville 1.21, Delano 1.33, Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 70, Parlier 71, Blackwell 81, Lindcove, 73, Arvin, 72, Orange Cove 73, Porterville 78, Delano 71
Record Temperatures: 102/46. Average Temperatures: 89/57
Cooling Degree Days this Season: 1971 +437
Courtesy of the NWS
Average temperature for September so far: 75.7 +1.4
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2017 Fresno: 6.73 season. or -4.70. Month to Date: .00
Since Oct 1, 2017, Bakersfield: 3.93, or -2.49. 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: 6:49 am Sunset: 6:57 pm. Hours of Daylight: 12:04
Yesterday’s Weather:
MAE : Madera 253 : DH1700 / 98 / 56 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 96 / 63 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 95 / 54 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 96 / 58 / 0.00 /
BFL : Bakersfield Airport 496 : DH1700 / 95 / 67 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 94 / 55 / 0.00 /
ATEC1 : Avenal 787 : DH1655 / 93 / 62 / 0.00 /
PTV : Porterville Airport 442 : DH1700 / 95 / 59 / 0.00 /
TFTC1 : Taft 759 : DH1653 / 94 / 72 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 93 / 67 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
Year % Last Y. % Ave. Annual ave.
STOCKTON 0.00 9.22 66 21.79 156 13.96 14.06
MODESTO 0.00 8.17 63 16.93 130 13.01 13.11
MERCED 0.00 7.06 57 16.05 129 12.42 12.50
MADERA 0.00 7.22 60 14.26 119 11.94 12.02
FRESNO 0.00 6.73 59 17.36 152 11.43 11.50
HANFORD 0.00 4.70 47 11.21 112 10.05 10.10
BAKERSFIELD 0.00 3.95 61 8.34 130 6.44 6.47
BISHOP 0.00 3.08 60 9.18 180 5.11 5.18
SALINAS 0.00 7.16 56 16.49 129 12.76 12.83
PASO ROBLES 0.00 9.62 76 16.17 127 12.69 12.78
SANTA MARIA 0.00 6.01 43 18.91 136 13.90 13.95
Next report: Tuesday, September 25