September 25, 2019
Summary: This may turn out to be the hottest day we will endure until sometime late next spring, although that’s not official. However, short term we have upper level high pressure off the northern California coast and an active tropical low situated over northwest Baja. The flow both at the surface and aloft is out of the northeast, which is an off shore flow. This always enhances the heating process as winds blow downslope and heat by compression. Hottest locations this afternoon will tease with the century mark, which is fairly close to record territory.
That low I alluded to located over northwest Baja will swing slightly further north through tonight, increasing the chance of showers and thunderstorms as far north as the Coachella Valley with a slight chance in extreme southeastern Kern County. However, to our north we have a significant area of low pressure in western Canada which is dropping southward. It will center over eastern Oregon and Washington Friday then, depending upon model of choice, somewhere near northeast California Saturday through Monday.
The cooling trend will begin tomorrow then will really engage Friday through the weekend and through the first couple of days of next week. That off shore flow currently underway will turn onshore, spreading marine air down the valley tomorrow afternoon. Cooler air aloft will begin to spread over the region as we end up along the southern portion of the developing low. Readings over the weekend, especially Sunday then through Tuesday, will end up in the 70s. this will be a dry system, however it does have decent dynamics so the chance of showers over the Sierra Nevada will be excellent with still a low possibility of light showers on the valley floor, mainly from Fresno County north, but especially along the Sierra Nevada foothills. Any amounts will likely be less than .10. the best chance for measurable rain to occur will be later Saturday through Monday.
By the middle of next week, the low will finally begin to shift into the Rocky Mountain region, allowing weak high pressure to follow. However, models for late next week through the following weekend are showing low pressure dominating the Gulf of Alaska with a trough down into the Pacific Northwest. This would have the tendency to maintain a westerly flow in the atmosphere, keeping pressure low enough for temperatures to remain fairly moderate.
Forecast: Mostly clear skies through Thursday night with occasional high clouds. Mostly clear, breezy, and cooler Friday. Partly cloudy Friday night. variable cloudiness Saturday through Tuesday. I want to keep a small chance of light showers in the forecast for Saturday afternoon through Monday, especially along the Sierra Nevada foothills from Fresno County north. Partly cloudy Tuesday night. mostly clear Wednesday.
Short Term:
| Madera 99/61/92/57/84 | Reedley 99/61/95/59/85 | Dinuba 98/59/93/56/84 |
| Porterville 99/61/94/59/86 | Lindsay 98/60/94/58/86 | Delano 100/64/94/61/86 |
| Bakersfield 100/70/94/65/87 | Taft 99/74/94/68/87 | Arvin 101/67/94/62/87 |
| Lamont 100/66/94/63/86 | Pixley 99/62/94/59/86 | Tulare 97/60/93/59/85 |
| Woodlake 98/60/93/59/85 | Hanford 98/62/94/59/86 | Orosi 98/60/94/57/85 |
Seven Day Forecast:
| Saturday
Small chance of showers 55/79 |
Sunday
Small chance of showers 49/76 |
Monday
Small chance of showers 44/75 |
Tuesday
Partly cloudy 43/75 |
Wednesday
Mostly clear 43/80 |
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 through Thursday morning will be at or less than 12 MPH in the afternoon. Winds tonight will be generally less than 6 MPH with periods of near calm conditions. Winds by Thursday afternoon will be out of the west at 10 to 15 MPH then out of the northwest at 10 to 20 MPH Friday and Saturday with local gusts to 35 MPH, mainly in Kings County and western Fresno County, but locally elsewhere.
Rain: Even though showers and thunderstorms will affect southern California as far north as the Coachella Valley through Thursday morning, the valley will remain rain free through at least Friday night. a more significant autumn type storm is developing in western Canada and will eventually center over eastern Oregon or perhaps northeastern California Saturday through Monday night. even though this system is pretty moisture starved, the atmospheric dynamics appear fairly strong. Light showers will become likely along the Sierra Nevada and I do feel it’s appropriate to maintain a low chance of light showers on the valley floor, mainly from Fresno County northward and with the greatest risk along the Sierra Nevada foothills. If precipitation does occur, amounts would be generally less than .10.
The rain threat will not be over until early Tuesday when this system finally begins to shift eastward. Dry weather can be expected Tuesday and for the remainder of next week.
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Afternoon Dew Points Today: Low to mid 50s. Kern: : Upper 40s to the lower 50s. Humidity values ranging from 20%/75% at Hanford. Bakersfield 15%/50%
Actual Humidity range September 24, 2019: Delano, 80%/24% Porterville, 79%/23%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 90%, tomorrow 80%. Bakersfield: Today: 90% Tomorrow: 90%
ET Rates Over the Past Seven Days: Stratford 1.42, Parlier 1.28, Blackwell Corner 1.30, Arvin 1.39, Orange Cove 1.40, Porterville 1.28, 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 70, Porterville 81, Delano 70
Record Temperatures: 100/43. Average Temperatures: 88/57
Cooling Degree Days this Season: 1958 +405
Courtesy of the NWS
Average temperature for September so far: 76.2 +2.0
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 11.85 season. or +.41. Month to Date: .00 -.11
Since Oct 1, 2018, Bakersfield: 7.82, or +1.37. Month to Date: .02 -.04
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: 6:50 am Sunset: 6:50 pm. Hours of Daylight: 12:00
Yesterday’s Weather:
MAE : Madera 253 : DH1700 / 92 / 55 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 93 / 64 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 94 / 57 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 93 / 54 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 91 / 66 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 91 / 56 / 0.00 /
ATEC1 : Avenal 787 : DH1700 / M / M / 0.00 /
PTV : Porterville Airport 442 : DH1700 / M / M / 0.00 /
TFTC1 : Taft 759 : DH1649 / 91 / 70 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 93 / 61 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
STOCKTON 0.00 18.60 133 9.22 66 13.97 14.06
MODESTO 0.00 13.47 103 8.17 63 13.02 13.11
MERCED 0.00 13.27 107 7.06 57 12.43 12.50
MADERA 0.00 11.42 95 7.22 60 11.96 12.02
FRESNO 0.00 11.85 104 6.73 59 11.44 11.50
HANFORD 0.00 9.50 95 4.70 47 10.05 10.10
BAKERSFIELD 0.00 7.82 121 3.95 61 6.45 6.47
BISHOP 0.00 8.48 166 3.08 60 5.12 5.18
SALINAS 0.00 13.89 109 7.16 56 12.77 12.83
PASO ROBLES 0.00 14.88 117 9.62 76 12.70 12.78
SANTA MARIA 0.00 15.68 113 6.01 43 13.91 13.95
Next report: Thursday, September 26