October 23, 2020
Summary: A complex weather patter will develop over the weekend. In the short term, upper level high pressure is located off the coast of the Pacific Northwest while a very cold trough of low pressure has engulfed the northern Rockies and much of the Midwestern U.S. I found a few locations below 0 over Montana and Wyoming early this morning. a weak upper low is also located several hundred miles off the southern California coast.
By Saturday night, a trough of very cold low pressure will drop from western Canada all the way down into Nevada by Sunday morning and into Arizona by Monday morning. the latest models indicate this will be a dry event for the valley with only light snow showers over the higher elevations of the Sierra Nevada. Light showers will be possible, mainly Sunday night and Monday morning, over southern California as that off shore low tracks eastward across the southern part of the state and interacts with that cold trough diving southward.
The main impact of this will be much cooler temperatures leading to temperatures we haven’t seen since last spring. By Monday afternoon and night, a big high will be building along the west coast while that cold trough remains over the interior west. This will create a north/northeast flow aloft which will drive dry air down the valley. Couple that with a very strong off shore flow and we should see a number of locations in the upper 30s Tuesday morning. I still feel there is a chance of low spots teasing with the freezing mark Tuesday and possibly again Wednesday morning.
That off shore high will slowly build inland by midweek, leading to a warming trend. Most models show that high remaining in place for the rest of the week, although a couple are indicating a weak low will develop somewhere near or over California Friday morning. at any rate, it does not appear there will be active weather associated with this feature. Even the two week outlook which now moves through the first week in November shows a persistent blocking pattern with high pressure over the west and a could trough of low pressure east of the Rockies.
Forecast: Mostly clear today. Mostly clear with occasional cloudiness Saturday. Partly cloudy Saturday night. variable cloudiness Sunday through Monday morning with a slight chance of sprinkles, mainly in the south valley, Sunday evening through Monday morning. clearing Monday afternoon. Mostly clear Tuesday through Friday with a warming trend.
Short Term:
Madera 80/46/78/45/71 | Reedley 80/47/79/46/72 | Dinuba 80/45/78/44/70 |
Porterville 81/46/79/44/72 | Lindsay 80/45/78/44/70 | Delano 81/50/79/47/71 |
Bakersfield 79/58/78/53/70 | Taft 80/48/78/54/70 | Arvin 81/51/79/50/70 |
Lamont 81/53/78/50/71 | Pixley 81/47/79/45/71 | Tulare 80/47/77/43/70 |
Woodlake 80/46/78/44/71 | Hanford 80/48/78/46/71 | Orosi 80/45/79/43/70 |
Seven Day Forecast:
Monday
AM sprinkles 39/68 |
Tuesday
Mostly clear 36/78 |
Wednesday
Mostly clear 41/81 |
Thursday
Mostly clear 42/82 |
Friday
Mostly clear 42/80 |
Two Week Outlook: October 29 through November 4: 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 12 MPH and variable in nature. Winds Saturday will be out of the west or northwest at 8 to 15 MPH with stronger gusts. Winds later Saturday night through Sunday evening will be out of the northwest at 10 to 20 MPH. Gusts to near 30 MPH are possible, mainly along the west side but locally elsewhere, decreasing Sunday night. Winds Monday will be generally ata or less than 15 MPH, however, along the far west side, winds out of the north to northeast at 10 to 20 MPH with stronger gusts are possible.
Rain Discussion: The chance of measurable rain late Sunday into Monday morning appears quite unlikely. A weak low moving through southern California will interact with a cold deep trough of low pressure, resulting in a chance of light showers over southern California Sunday night and Monday morning. it’s possible a few sprinkles could occur in the south valley, mainly in Kern County, due to upsloping against the valley facing walls of the Tehachapi Mountains. By Monday afternoon and for the remainder of next week, expect a return to a dry weather pattern.
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 23, 2020:
Today’s air quality is listed as moderate for the entire valley.
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, 97%/32%, Porterville, 94%/28%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 100%, tomorrow 100%. Bakersfield: Today: 100% Tomorrow: 100%
ET Rates Over the Past Seven Days: Stratford 1.03, Parlier .87, Blackwell Corners .98, Arvin 1.10, Orange Cove .97, Porterville .76, Delano .87. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 69, Parlier 70, Blackwell NA, Arvin, 71, Orange Cove 74, Porterville 73, Delano 66
Record Temperatures: 90/35. Average Temperatures: 76/47
Heating Degree Days This Season: 0, -53
Courtesy of the NWS
Average Temperature for September So Far: 71.8 +6.5
Precipitation: Seasonal total for Fresno, .00, -.36 Month to Date: .00, -.36
Precipitation for Bakersfield, Season, .00, +or- -.16. Month to date .00, -.16
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: 7:15 Sunset: 6:10 pm Hours of Daylight: 10:56
Yesterday’s Weather
MCE : Merced 153 : DH1700 / 81 / 49 / 0.00 /
MAE : Madera 253 : DH1700 / 83 / 49 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 84 / 59 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 85 / 51 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 85 / 52 / 0.00 /
BFL : Bakersfield Airport 496 : DH1700 / 85 / 61 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 84 / 56 / 0.00 /
ATEC1 : Avenal 787 : DH1700 / 81 / 58 / 0.00 /
PTV : Porterville Airport 442 : DH1700 / 86 / 57 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 79 / 56 / 0.00 /
Rainfall: 24hr W.Y. % Last Y. % Ave. Year ave.
STOCKTON 0.00 0.00 0 0.00 0 0.46 14.06
MODESTO 0.00 0.00 0 0.00 0 0.40 13.11
MERCED 0.00 0.00 0 0.00 0 0.39 12.50
MADERA 0.00 0.00 0 0.00 0 0.42 12.02
FRESNO 0.00 0.00 0 0.00 0 0.36 11.50
HANFORD 0.00 0.00 0 0.00 0 0.25 10.10
BAKERSFIELD 0.00 0.00 0 0.00 0 0.16 6.47
BISHOP 0.00 0.00 0 0.00 0 0.19 5.18
SALINAS 0.00 T 0 0.00 0 0.35 12.83
PASO ROBLES 0.00 0.00 0 0.00 0 0.35 12.78
SANTA MARIA 0.00 0.00 0 0.00 0 0.32 13.95
Next report: October 24, 2020