October 24, 2020
Summary: The weather pattern over the western U.S. is rapidly changing. By the time we get into Tuesday morning, touches of winter will be in the air. A cold trough of low pressure is currently digging southward from western Canada and stretches from eastern Washington to the northern Rockies. By Sunday morning, this trough will be digging southward into Nevada and Utah and eventually into Arizona and inland sections of southern California. In the meantime, a very weak upper low off the central coast will be tugged inland through southern California and northern Baja Sunday. It will be absorbed by the incoming trough over the interior west. As each set of forecast models comes out, it becomes more clear that no precipitation will occur in California other than some light snow flurried over the higher elevations of the Sierra Nevada.
A dry cold front will barrel through central California Sunday evening, issuing in an air mass which will result in the need to wear a coat Monday through Tuesday mornings. At the surface, a very strong off shore flow will develop late Sunday night and Monday as pressure over Idaho and Nevada rapidly rises behind the low which by then will be in eastern Arizona. The combination of this off shore flow and a big upper high building along the Pacific coast will generate a north/south flow aloft, driving dry air down the valley. Depending on where dew points end up, colder locations Tuesday and possibly Wednesday mornings will dip into the mid to upper 30s and again it’s possible isolated low spots could brush with the freezing mark. It’s possible upslope clouds could begin to bank up against the north facing slopes of the Tehachapi Mountains all the way into Tuesday morning and ditto that along the Sierra Nevada foothills, mainly in Tulare County. However, typically with a robust off shore flow and dry air moving in from t he north the clouds dissipate rather quickly.
Incidentally, yesterday was the first time since last spring that the valley did not reach the 80 degree mark.
The high off the Pacific coast will begin to shift eastward into California Tuesday for the beginning of a significant warming trend. Temperatures for much of next week from midweek on will average in the low to mid 80s, possibly marginally falling next weekend.
Longer range models are indicating an excellent chance of dry weather will continue with above average temperatures, or in other words, we’ll go back to the same old blocking pattern.
Forecast: Partly cloudy through Sunday. Mostly cloudy Sunday night and Monday morning. Clearing Monday afternoon but possibly remaining mostly to partly cloudy in Kern County through Monday night. mostly clear Tuesday through Saturday with a warming trend.
|Madera 77/46/71/40/70||Reedley 78/45/73/41/69||Dinuba 77/45/72/39/69|
|Porterville 78/46/73/40/70||Lindsay 78/45/72/39/69||Delano 78/49/73/43/71|
|Bakersfield 76/52/70/49/70||Taft 77/53/70/52/71||Arvin 78/50/71/47/69|
|Lamont 79/50/73/45/69||Pixley 77/46/73/40;70||Tulare 77/45/72/39/69|
|Woodlake 77/45/72/39/70||Hanford 77/47/72/43/71||Orosi 77/45/71/38/68|
Seven Day Forecast:
Two Week Outlook: October 31 through November 6: This model flips us back into more of an amplified pattern with high pressure over the west and a colder trough east of the Rockies. Therefore, rain appears unlikely during this period with a return to above average temperatures.
October: This model essentially depicts the entire lower 48 with above average temperatures over the next 30 days. The most pronounced temperature anomalies will be over the Desert Southwest. This model also suggests there will be an equal chance of above or below average precipitation.
October, November, December: This model reflects the influence of La Nina. It paints above average temperatures over much of the country, especially the Desert southwest, and to a lesser extent, central California. Drier than average conditions are anticipated over southern California while northern California could possibly luck out with near average rainfall. Above average precipitation is expected over the Pacific Northwest.
Winds Discussion: Winds through tonight will be generally at or less than 15 MPH. winds Sunday will be out of the northwest at 10 to 15 MPH. Local gusts to 30 MPH are possible by evening, mainly along the west side. Winds Sunday night will be out of the northwest at 10 to 20 MPH with stronger gusts. Winds Monday will be generally at or less than 12 MPH with the exception of the far west side where winds will be out of the north to northeast at 15 to 25 MPH, diminishing Monday evening. Winds Monday night and Tuesday will be generally light.
Rain Discussion: Expect dry conditions for at least the next 7 to 10 days.
Air Quality Expectations: With the tremendous amount of smoke over the valley floor, the San Joaquin Valley Air Pollution Control District has issued the following warning(s) for October 24, 2020:
Today’s air quality is listed as moderate for the valley up to Fresno and Madera Counties. The air quality north of that line is posted as good.
The District’s Real-time Air Advisory Network (RAAN) can be used to track air quality at any Valley location by visiting myRAAN.com. The option to use a specific address is available.
For more information on wildfires affecting the Valley’s air, visit: http://www.valleyair.org/wildfires
In addition, anyone can follow air quality conditions by downloading the free “Valley Air” app on their mobile device
Afternoon Dew Points Today: Mid to upper 40s. Mid to upper 40s.
Actual Humidity Range Yesterday: Delano, 99%/19%, Porterville, 89%/18%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 100%, tomorrow 100%. Bakersfield: Today: 100% Tomorrow: 100%
ET Rates Over the Past Seven Days: Stratford 1.04, Parlier .86, Blackwell Corners .98, Arvin 1.09, Orange Cove .94, Porterville .75, Delano .87. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 68, Parlier 70, Blackwell NA, Arvin, 71, Orange Cove 74, Porterville 72, Delano 66
Record Temperatures: 95/36. Average Temperatures: 76/47
Heating Degree Days This Season: 2, -55
Courtesy of the NWS
Average Temperature for September So Far: 71.4 +6.3
Precipitation: Seasonal total for Fresno, .00, -.39 Month to Date: .00, -.39
Precipitation for Bakersfield, Season, .00, +or- -.17. Month to date .00, -.17
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, Parlier, Arvin, Shafter, Stratford, Delano, Lindcove, Porterville
Hours at 45 or below 45.
Sunrise: 7:16 Sunset: 6:09 pm Hours of Daylight: 10:54
MCE : Merced 153 : DH1700 / 78 / 48 / 0.00 /
MAE : Madera 253 : DH1700 / 78 / 45 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 80 / 54 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 79 / 47 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 80 / 48 / 0.00 /
BFL : Bakersfield Airport 496 : DH1700 / 76 / 58 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 79 / 48 / 0.00 /
ATEC1 : Avenal 787 : DH1625 / 78 / 55 / 0.00 /
PTV : Porterville Airport 442 : DH1700 / 76 / 51 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 77 / 51 / 0.00 /
Rainfall: 24hr W.Y. % Last Y. % Ave. Year ave.
STOCKTON 0.00 0.00 0 0.00 0 0.49 14.06
MODESTO 0.00 0.00 0 0.00 0 0.43 13.11
MERCED 0.00 0.00 0 0.00 0 0.42 12.50
MADERA 0.00 0.00 0 0.00 0 0.45 12.02
FRESNO 0.00 0.00 0 0.00 0 0.39 11.50
HANFORD 0.00 0.00 0 0.00 0 0.26 10.10
BAKERSFIELD 0.00 0.00 0 0.00 0 0.17 6.47
BISHOP 0.00 0.00 0 0.00 0 0.20 5.18
SALINAS 0.00 T 0 0.00 0 0.36 12.83
PASO ROBLES 0.00 0.00 0 0.00 0 0.38 12.78
SANTA MARIA 0.00 0.00 0 0.00 0 0.35 13.95
Next report: October 26, 2020