September 24, 2019
Summary: The center of circulation of low pressure which 24 hours ago was over western Nevada has shot southward and is now centered over northern Baja. Upper level high pressure off the northern California coast is now bulging inland into northern and central California. The freezing level is now at 17,100 feet and the marine layer has been crushed down to just 400 feet at Monterey. The winds aloft between the high off the north coast and that low to our south are out of the northeast. This is an off shore flow. The combination of downslope heating off the mountains and building high pressure aloft will result in a temporary warming trend which will peak Wednesday when hottest locations will tease with the century mark.
That low over northern Baja is forecast to remain stationary for the next 24 hours then jog slowly northeastward. This system has a great deal of tropical moisture in it from former hurricane Lorena. That jog to the northeast will spread showers and thunderstorms over the lower deserts of California, but that off shore flow will ensure no effect will be felt on central California.
The high will begin to weaken Thursday and will be suppressed to the southwest, allowing a substantial area of cold low pressure to drop southward, centering over eastern Washington and Oregon by late Friday. It will dig a trough southward over and along the west coast. Since the center of circulation of this player will be overland, the chance for precipitation for central California is considerably less. For now, it appears the only areas to receive rain Friday night through Monday will be the Sierra Nevada with a small chance of showers over the Tehachapi Mountains due to upsloping.
A strong westerly flow wrapping around the bottom side of this system will be right over central California this weekend and into the early part of next week. Typically, a pattern like this causes cloud cover to be banked against the west slopes of the Sierra Nevada and the northwest facing slopes of the Kern County mountains. The combination of much cooler air associated with the trough and cloud cover will keep temperatures in the 70s Saturday through at least Monday. It will be next Wednesday before the low begins to pull off towards the northeast, allowing upper level high pressure to finally begin to fill in from the west for the beginning of the next warming trend.
Forecast: Mostly clear skies through Friday morning. Partly cloudy Friday afternoon and Friday night. variable cloudiness Saturday through Monday with a slight chance of light showers, mainly near the foothills of the Tehachapi Mountains and the Sierra Nevada. Partly cloudy Monday night and Tuesday.
Short Term:
| Madera 93/59/98/60/93 | Reedley 93/60/98/61/95 | Dinuba 92/59/97/59/94 |
| Porterville 94/59/98/61/95 | Lindsay 93/58/98/60/94 | Delano 94/64/98/66/95 |
| Bakersfield 94/67/100/71/96 | Taft 93/73/99/72/95 | Arvin 94/64/101/67/96 |
| Lamont 94/64/100/69/95 | Pixley 94/59/98/61/95 | Tulare 92/58/96/59/95 |
| Woodlake 93/59/98/61/94 | Hanford 93/60/98/61/94 | Orosi 92/58/97/60/94 |
Seven Day Forecast:
| Friday
Mostly clear 58/86 |
Saturday
Mostly cloudy 52/77 |
Sunday
Mostly cloudy 46/74 |
Monday
Mostly cloudy 46/73 |
Tuesday
Partly cloudy 43/81 |
Two Week Outlook: October 1 through October 7: This model is indicating upper level high pressure will keep temperatures somewhat above average for the first week in October. Although moisture may be feeding into the Desert Southwest, dry conditions should prevail for central California.
September: This model is indicating below average precipitation for Oregon and northern California and above average precipitation over Arizona and extreme southern California. Central California comes into the “near average” category. Generally, below average rainfall over northern California is duplicated in central California. As usual, this model projects above average temperatures.
October, November, December: I never put much credence in the 90 day forecast, but nevertheless, we’ll put on paper what NOAA is projecting. This model is projecting near average precipitation over central and southern California and below average rain once you get near the Oregon border. So, going by this guide, one would think precipitation would be near average with above average temperatures.
Winds: Winds will be generally at or less than 15 MPH afternoons and evenings through Thursday and mainly out of the northwest. Winds during the night and morning hours will be generally at or less than 6 MPH with periods of near calm conditions. Winds Friday will initially increase out of the west at 10 to 20 MPH then become out of the northwest Friday night at 10 to 20 MPH with gusts to 30 MPH possible, especially in much of Kings County and western Fresno County.
Rain: Models continue to point to drier conditions for this weekend as each set of computer models comes across my desk. The center of circulation is projected to center over eastern Washington and Oregon, meaning this storm is largely overland. The best chance of rain for central California will be over the higher terrain with only a slight chance of sprinkles or isolated light showers mainly near the base of the Sierra Nevada and the Kern County mountains. As of this juncture, it appears most and possibly all locations will remain dry. The slight risk begins Saturday morning and will continue through Monday with dry weather thereafter.
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Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: : Mid to upper 40s. Humidity values ranging from 20%/75% at Hanford. Bakersfield 20%/50%
Actual Humidity range September 23, 2019: Delano, 79%/30% Porterville, 78%/26%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 90%, tomorrow 100%. Bakersfield: Today: 90% Tomorrow: 100%
ET Rates Over the Past Seven Days: Stratford 1.41, Parlier 1.28, Blackwell Corner 1.28, Arvin 1.38, Orange Cove 1.39, Porterville 1.27, Delano 1.26. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 72, Parlier 72, Blackwell 83, Arvin, NA, Orange Cove 71, Porterville 81, Delano 70
Record Temperatures: 102/46. Average Temperatures: 89/57
Cooling Degree Days this Season: 1947 +401
Courtesy of the NWS
Average temperature for September so far: 76.2 +1.9
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 11.85 season. or +.42. Month to Date: .00 -.10
Since Oct 1, 2018, Bakersfield: 7.82, or +1.38. Month to Date: .02 -.03
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, Parlier, Arvin, Shafter, Stratford, Lindcove, Porterville,
Hours at 45 or below 45.
Sunrise: 6:49 am Sunset: 6:51 pm. Hours of Daylight: 12:05
Yesterday’s Weather:
MAE : Madera 253 : DH1700 / 88 / 57 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 89 / 64 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 90 / 61 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 90 / 57 / 0.00 /
BFL : Bakersfield Airport 496 : DH1700 / 89 / 63 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 89 / 56 / 0.00 /
ATEC1 : Avenal 787 : DHM / M / M / M /
PTV : Porterville Airport 442 : DHM / M / M / 0.00 /
TFTC1 : Taft 759 : DH1659 / 86 / 68 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 87 / 59 / 0.00 /
:
:
:These data are preliminary and have not undergone final quality
:control by the National Climatic Data Center /NCDC/. Therefore
:these data are subject to revision. Final and certified climate
:data can be accessed at www.ncdc.noaa.gov.
Rainfall: Water year Oct 1st through September 30th
STOCKTON 0.00 18.60 133 9.22 66 13.96 14.06
MODESTO 0.00 13.47 104 8.17 63 13.01 13.11
MERCED 0.00 13.27 107 7.06 57 12.42 12.50
MADERA 0.00 11.42 96 7.22 60 11.94 12.02
FRESNO 0.00 11.85 104 6.73 59 11.43 11.50
HANFORD 0.00 9.50 95 4.70 47 10.05 10.10
BAKERSFIELD 0.00 7.82 121 3.95 61 6.44 6.47
BISHOP 0.00 8.48 166 3.08 60 5.11 5.18
SALINAS 0.00 13.89 109 7.16 56 12.76 12.83
PASO ROBLES 0.00 14.88 117 9.62 76 12.69 12.78
SANTA MARIA 0.00 15.68 113 6.01 43 13.90 13.95
Next report: Wednesday, September 25