January 17, 2021
For today, expect one more day of well above average temperatures under clear skies and leave it at that so I can concentrate on a rare weather pattern which is already beginning to unfold. There is a weak low pressure system located off the coast of the Pacific Northwest at this hour which will race southward along the coast and begin to close up and form a closed low pressure system just off the central coast late tonight. by Monday, this system will be intensifying off the southern California coast. By later Monday night and Tuesday morning, the center of circulation of a now cut off low will be just off the northern Baja coastline.
In the meantime, a very strong surface high will center over Idaho and Montana while at the mid and upper levels of the atmosphere, the high, which has resulted in recent tranquil weather, will shift further out over the ocean, building a southwest to northeast ridge into the Pacific Northwest and southwest Canada. The squeeze play between the eastern rim of the high and the low off of Baja will generate first, a very strong northeast flow aloft late tonight and Monday, becoming easterly Monday night and Tuesday morning. this rare configuration creates a very strong off shore flow at all levels of the atmosphere and also presents some intriguing weather possibilities.
Mono winds are rare along the Sierra Nevada, but when they do happen they can be quite dramatic. Winds exceeding 60 MPH are possible, especially along east to west facing canyons from Kings Canyon north. Monday night and Tuesday morning looks to be the best window of opportunity for this to occur.
In the meantime, a powerful Santa Ana wind event will occur in southern California. Some of the typically windy spots could see winds exceed 100 MPH. the main question I have is whether these winds will work their way downslope off the Tehachapi and into the extreme south valley. If this occurs, local gusts of 70 to 80 MPH could not be ruled out at places like the bottom of the Grapevine., locations such as Arvin and Lamont could conceivably see winds of 60 to 70 MPH and even as far north as Bakersfield, gusts exceeding 45 MPH could not be ruled out.
These winds are notoriously difficult to nail down. Many times, they remain just above the valley floor. For growers, the best advice I can give is that the proper configuration is there for a strong wind event beginning Monday afternoon and lasting through Tuesday morning.
The low off of Baja will pick up moisture and spread showers into southern California, possibly as far north as LA County. However, there’s no reason to believe precipitation will track this far north. The Baja low will be kicked eastward Wednesday night as the next feature of note in the form of a very cold low drops southward from western Canada and into California Friday and Saturday. models still indicate this system will lack moisture, but I do believe it’s our only hope at measurable rain this week. After this weekend, models do show a possibly active pattern, one which would result in well below average temperatures and low snow levels.
Forecast: After the patchy morning fog burns off, expect hazy sunshine this afternoon. Mostly clear tonight. partly cloudy at times Monday through Wednesday with a chance of strong, gusty winds in Kern County Monday afternoon through Tuesday morning. mostly clear Wednesday night. increasing cloudiness later Thursday and Thursday night. a chance of light showers Friday through Saturday morning. partly cloudy Saturday afternoon through Sunday.
Short Term:
| Madera 67/37/65/35/62 | Reedley 69/37/68/34/64 | Dinuba 67/36/67/33/63 |
| Porterville 71/35/68/34/63 | Lindsay 70/36/68/33/63 | Delano 70/38/67/39/62 |
| Bakersfield 72/48/70/45/62 | Taft 68/54/63/45/60 | Arvin 72/40/71/48/62 |
| Lamont 71/38/67/48/62 | Pixley 70/38/68/34/63 | Tulare 66/34/67/33/62 |
| Woodlake 68/36/68/33/61 | Hanford 68/39/68/34/62 | Orosi 68/35/68/33/61 |
Seven Day Forecast:
| Wednesday
Mostly clear 32/61 |
Thursday
Partly cloudy 31/63 |
Friday
Chance of showers 39/66 |
Saturday
AM showers possible 41/56 |
Sunday
Partly cloudy 37/57 |
Two Week Outlook: January 24 through January 30: This model paints roughly 80% of the lower 48 with below average temperatures, including California. It also indicates there will be an active pattern over the western U.S. with a greater potential for precipitation.
January: This model doesn’t really show a trend for temperatures at all. We’ll call it near average this time around. Not surprisingly, it does indicate January will have below average precipitation, as has been the case this La Nina year.
January, February, March: This model does not really offer much hope for a decent rainy season as below average precipitation is indicated over the Golden State. Temperatures over this 90 day period will be generally above seasonal average.
Winds Discussion: “Winds will be light and variable through tonight. a very rare configuration will set up Monday afternoon through Tuesday morning as a very strong off shore flow at all levels of the atmosphere align from east to west. This is one of the proper configurations I look for foro high winds in the extreme south valley. On most occasions, these winds blow over the top of the valley, but occasionally they don’t and the risk factor this time around I put at higher than normal. If these winds do make it down to the valley’s surface, gusts of 70 to 80 MPH cannot be ruled out at places like the bottom of the Grapevine. Locations like Mettler and Taft could see winds exceeding 50 MPH while locations such as Arvin and Lamont conceivable could see winds stronger than 60 MPH. Again, if these winds do make it downslope and down to the valley floor, gusts could exceed 40 MPH as far north as Bakersfield. the Sierra Nevada blocks these winds from the remainder of the valley, where winds will be generally at or less than 15 MPH with the exception of the far west side where north to northeast winds could exceed 40 MPH.
Again, all of this has the greatest chance of occurring Monday afternoon through Tuesday morning.
Winds Wednesday could still reach the extreme south valley but not as strong, generally at or less than 30 MPH with light winds Wednesday night and Thursday.
Rain Discussion: Dry weather will continue through Thursday night. a very cold low will drop into California Friday through Saturday. on paper, this system looks starved for moisture. Even so, if it’s going to rain this week it will be Friday through Saturday with a chance of light showers. Models show an active pattern beginning Monday of next week for additional chances of precipitation. Let’s hope these models don’t hang us out to dry again.
Frost Discussion: All locations will be above 32 degrees Monday morning. Tuesday morning’s forecast will be very difficult to nail down. The strong off shore flow explained above will dry out the air mass on the valley floor, bringing down dew points. However, there will be tremendous wind energy above the valley floor Tuesday, creating mixing. It’s possible wind sheltered locations, especially along the east side, could briefly dip into the 20s with most locations in the 30s. in Kern County, if these winds occur, temperatures may not drop out of the 50s.
There will be a greater risk of upper 20s Wednesday morning. It’ s possible, however, that the cloud canopy from the low to our south could circulate far enough to the north to keep temperatures above freezing. Thursday morning may be the best chance for below average temperatures as the Baja low races off to the west, leaving mostly clear skies. For now, I’m not going to forecast anything colder than upper 20s and lower 30s. increasing clouds and a chance of showers will keep temperatures above freezing as we enter into a cold but active weather pattern.
Lows Tonight: All locations will be above 32 tonight.
Afternoon Dew Points Today: Upper 40s to the lower 50s. Mid to upper 40s.
Actual Humidity Range Yesterday: Delano, NA Porterville, NA
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 90%, tomorrow 80%. Bakersfield: Today: 90% Tomorrow: 70%
ET Rates Over the Past Seven Days: ET information has been unavailable for the past seven days. Seventy two hours. Stratford .NA, Parlier .NA, Blackwell Corners .NA, Arvin .NA, Orange Cove .NA, Porterville .NA, Delano .NA. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 53, Parlier 50, Blackwell 53, Arvin, 52, Orange Cove 52, Porterville NA, Delano 46
Record Temperatures: 74/20. Average Temperatures: 55/35
Heating Degree Days This Season: 1199. Varies widely from location to location. courtesy of the NWS
Average Temperature for this month So Far: 48.8 +4.4 courtesy of the NWS
Precipitation: Seasonal total for Fresno, 1.42, or -3.22 or 31% of average. Month to Date: .T or -1.17
Precipitation for Bakersfield, Season, .74, +or- -1.82, or 29% of average. Month to date .00, or -.60
Water year season is from October 1st through September 30.
Chilling Hours November 1st through February 28: Orange Cove, 670, Parlier, 784, Arvin, 640, Belridge, 727, Shafter, 737, Stratford, 746, Delano, 806, Porterville, 750
Hours at 45 or below 45. Courtesy UC Davis
Sunrise: 7:09 am Sunset: 5:10 pm Hours of Daylight: 9:59
Yesterday’s Weather
MCE : Merced 153 : DH1600 / 65 / 38 / 0.00 /
MAE : Madera 253 : DH1600 / M / 42 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 65 / 43 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 66 / 36 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 70 / 36 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 69 / 41 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 64 / 38 / 0.00 /
ATEC1 : Avenal 787 : DH1538 / 68 / 41 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 70 / 38 / 0.00 /
TFTC1 : Taft 759 : DH1600 / 67 / 37 / 0.00 /
Rainfall: 24hr W.Y. % Last Y. % Ave. Year ave.
STOCKTON 0.00 2.09 34 5.14 84 6.13 14.06
MODESTO 0.00 1.54 29 3.85 71 5.40 13.11
MERCED 0.00 2.28 44 0.00 0 5.16 12.50
MADERA 0.00 0.77 15 0.00 0 5.30 12.02
FRESNO 0.00 1.42 31 0.00 0 4.64 11.50
HANFORD 0.00 0.67 15 0.00 0 4.54 10.10
BAKERSFIELD 0.00 0.74 29 0.00 0 2.56 6.47
BISHOP 0.00 0.21 9 1.16 51 2.27 5.18
SALINAS 0.00 0.96 18 5.86 112 5.23 12.83
PASO ROBLES 0.00 0.99 19 6.61 130 5.10 12.78
SANTA MARIA 0.00 1.77 32 4.77 88 5.45 13.95
Next report: January 17/pm