September 13, 2017
Summary: Suddenly the marine layer along the coast has deepened to nearly 3,000 feet. The sea breeze is surging through the Delta and through other gaps and passes along the Coast Range. In fact, winds at Pacheco Pass are currently gusting to 35 MPH. this will usher in a long awaited cooling trend which will cause temperatures to drop to below average through the rest of the week. All this is due to an upper low just to the southwest of Monterey. There are a few showers and isolated thunderstorms near the center of circulation, but most of central California is relatively cloud free.
The low is projected to move eastward through probably Kern County early tomorrow. With this feature so close, and daytime heating, scattered showers and thunderstorms will no doubt break out over the Sierra Nevada and possibly the Kern County mountains. I wouldn’t be totally shocked to see a few cells over the Coast Range.
As the low passes inland, widely scattered showers and isolated thunderstorms will be possible through tonight, mainly beginning later this afternoon. By Thursday morning, the low will be absorbed by a new trough of low pressure which will send temperatures even lower. Only moderate warming will occur over the weekend, but by early next week a new low will be digging into northern California, once again increasing the on shore flow with plenty of marine air moving inland to renew the below average temps. After tonight, no precipitation is expected in the medium term.
Forecast: Mostly clear this morning. Mostly clear to occasionally partly cloudy late this afternoon through tonight with a small chance of widely scattered showers and isolated thunderstorms. Partly cloudy and cooler Thursday. Mostly clear Thursday night and on through Wednesday of next week.
Short Term:
| Madera 87/62/85/57/84 | Reedley 89/64/87/60/85 | Dinuba 88/63/87/59/84 | |
| Porterville 90/64/87/58/85 | Lindsay 90/63/87/57/84 | Delano 90/65/87/61/86 | |
| Bakersfield 90/66/85/63/85 | Arvin 91/65/88/64/86 | Taft 89/70/87/66/86 | |
| Lamont 90/66/88/63/8653 | Pixley 89/64/87/58/85 | Tulare 90/63/87/57/85 | |
| Woodlake 90/63/87/58/84 | Hanford 90/63/87/57/85 | Orosi 90/62/86/57/85 | |
Seven Day Forecast:
| Saturday
Mostly clear 57/88 |
Sunday
Mostly clear 61/89 |
Monday
Mostly clear 58/85 |
Tuesday
Mostly clear 55/80 |
Wednesday
Mostly clear 53/79 |
Two Week Outlook: September 20 through September 26: This model shows a pretty active pattern moving into the Pacific Northwest and clipping northern California. For now, it does not appear precipitation will affect central California, but this regime should keep temperatures near to slightly below average.
September: This model shows upper level high pressure more dominant over the western U.S. There’s no clear indicator of above or below average rainfall as we move into the fall season. With that in mind, we’ll call for near average precipitation for the month.
September, October, November: It appears temperatures overall will rise to above average values for the bulk of this time frame. Upper level high pressure is also more dominant with precipitation, believe it or not, predicted to be somewhat near average.
Winds: Winds will be generally out of the northwest at 10 to 15 MPH through Thursday. Along the west side, especially along the Interstate 5 corridor, winds gusting to near 30 MPH are possible. Winds Thursday night through Saturday will be generally in the 5 to 15 MPH range with stronger gusts.
Rain: The center of circulation around an upper low is just to the southwest of Monterey this morning. This feature is forecast to move inland by tomorrow morning, possibly over Kern County. The fact that it’s so close means scattered showers and isolated thunderstorms could develop over the Sierra Nevada, the Kern County mountains and the Coast Range. I don’t anticipate any action until possibly late this afternoon through the early morning hours Thursday. Most of the valley will remain dry, however isolated showers and thunderstorms are possible during this time frame. By Thursday morning, the low will be absorbed by an incoming trough of low pressure, ending the chance of precipitation.
Expect dry conditions from Thursday through at least the middle of next week. In fact, there’s no suggestion on models for precipitation through all of next week.
Afternoon Dew Points Today: Upper 50s to the lower 60s. Kern: Mid to upper 50s.
Relative Humidity Forecast: Hanford, 30%/75% Bakersfield, 30%/60%
Actual Humidity September 11, 2017: Delano, 87%/29%, Porterville, 84%/24%
Percentage of Sunshine Today/Tomorrow: Visalia: Today 80% tomorrow 80%, Bakersfield: Today 90% tomorrow 90%.
ET Rates Over the Past Seven Days September 11, 2017: Stratford 1.58, Parlier 1.23, Blackwell 1.51, Lindcove 1.32, Arvin 1.51, Orange Cove 1.45, Porterville 1.23, Delano 1.38, Madera Two 1.26 Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 77, Parlier 83, Blackwell 82, Lindcove 79, Arvin 1.89, Orange Cove 81, Porterville 85, Delano 81, Madera Two 83
Mean Temperatures for September Month So Far: 84.0 +8.0
Record Temperatures: 105/48. Average Temperatures: 92/61
Cooling Degree Days This Season: 2029, +582 Courtesy of the NWS
Precipitation: Seasonal total/average/above or below average:
Since September 11, 2017, Fresno: 17.20 season. or +5.94. Month to Date: T
Since September 11, 2017, Bakersfield: 7.89, or 1.43, Month to Date: .01, Water year season is from October 1st through September.
Chilling Hours November 1st Through February 28: Orange Cove, Parlier, Arvin, Shafter, , Stratford, Madera two, Alpaugh, Delano, Lindcove, Porterville, Hours at 45 or below 45.
Sunrise: 6:39 am Sunset: 7:10 Hours of Daylight: 12:36
Yesterday’s Weather
MCE : Merced 153 : DH1700 / 95 / 64 / T /
MAE : Madera 253 : DH1700 / 96 / 68 / 0.08 /
FAT : Fresno Airport 333 : DH1700 / 96 / 70 / 0.10 /
HJO : Hanford Airport 242 : DH1700 / 96 / 68 / 0.11 /
NLC : Lemoore Naval AS 234 : DH1700 / 99 / 72 / T /
BFL : Bakersfield Airport 496 : DH1700 / 99 / 75 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 96 / 67 / 0.08 /
ATEC1 : Avenal 787 : DH1656 / 97 / 68 / 0.00 /
PTV : Porterville Airport 442 : DH1700 / 97 / 69 / 0.01 /
TFTC1 : Taft 759 : DH1650 / 96 / 72 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 95 / 72 / M /
Rainfall:
To date Last year Average Annual ave
STOCKTON T 21.79 158 16.69 121 13.83 14.06
MODESTO T 16.93 131 15.61 121 12.90 13.11
MERCED 0.00 16.03 130 14.66 119 12.29 12.50
MADERA 0.00 14.26 120 12.96 109 11.84 12.02
FRESNO 0.00 17.30 152 14.29 126 11.36 11.50
HANFORD 0.00 11.16 112 8.26 83 9.97 10.10
BAKERSFIELD 0.00 7.83 122 5.43 85 6.41 6.47
BISHOP 0.00 9.18 183 3.88 77 5.03 5.18
SALINAS 0.00 16.49 130 13.47 106 12.69 12.83
PASO ROBLES 0.00 16.17 128 8.06 64 12.59 12.78
SANTA MARIA 0.00 18.91 137 9.00 65 13.84 13.95
Rainfall season from October 1st through September 30th
Next Report: Thursday, September 14