January 29, 2020
Summary: Considerable upslope clouds continue to regenerate along the valley facing slopes of the Kern County mountains and the west facing slopes of the Sierra Nevada. A low overcast based anywhere from 1600 feet over Visalia to 3,700 feet over Bakersfield will be slow in clearing. Nevertheless, most areas will see some sunshine this afternoon.
A low pressure system that moved through the Pacific Northwest yesterday has dived southeastward, carving out an elongated low from eastern Nevada to western Arizona. The combination of this low pressure system and upper level high pressure building in from the west has created a northerly flow. This will continue through Thursday. The air mass is marginally cooler than 24 hours ago, but no frost concerns are at hand in the short term forecast.
The center of circulation of the high will be just to our west Friday through Sunday, driving temperatures into the mid to upper 60s. that, of course, is assuming fog and low clouds don’t completely take over, in which case daytime highs would be ten degrees lower than forecast.
The high will rapidly be suppressed southward Sunday night in response to a cold low dropping southward from the eastern Gulf of Alaska which will dive into the western Great Basin just to the east of the Sierra Nevada Monday. While that’s developing, a massive high over the eastern Pacific will build into Alaska. That means a squeeze play between the cold trough just to our east and the off shore high will create a north/south flow right down the west coast and into California. This has been a season with very little serious frost concerns. It appears more and more that this will change early next week as modified arctic air moves into the western U.S. The coldest air will remain east of the Sierra Nevada. Even so, temperatures will fall below average next week, which is discussed in the frost section below.
A rather dynamic cold front will move down the valley Sunday night or Monday morning. however, with that low taking largely an overland trajectory, any precipitation will be confined to the Sierra Nevada with only a slight chance over the valley floor.
Forecast: Widespread fog and low overcast nights and mornings with hazy sunshine in the afternoon in most areas through Saturday night. increasing cloudiness by late Sunday. Mostly cloudy, breezy, and cooler Sunday night and Monday morning with a slight chance of showers. Partly cloudy and breezy Monday afternoon and night. mostly clear to occasionally partly cloudy Tuesday through Wednesday and much cooler.
Short Term:
| Madera 57/37/61/38/65 | Reedley 56/37/61/38/66 | Dinuba 55/37/60/38/65 | |
| Porterville 56/38/61/39/66 | Lindsay 56/37/62/39/66 | Delano 57/40/61/41/67 | |
| Bakersfield 55/43/62/44/69 | Taft 57/43/62/45/68 | Arvin 55/40/62/43/69 | |
| Lamont 55/41/62/43/68 | Pixley 56/38/61/39/66 | Tulare 56/37/60/39/65 | |
| Woodlake 55/37/61/39/65 | Hanford 57/40/61/43/67 | Orosi 55/36/61/38/65 | |
Seven Day Forecast:
| Saturday
Am fog/pm sun 40/67 |
Sunday
Am fog/partly cloudy 40/55 |
Monday
Slight chance of showers 33/52 |
Tuesday
Mostly clear 30/54 |
Wednesday
Mostly clear 30/55 |
Two Week Outlook: February 3 through February 9: This model indicates a large high will be off the north American continent with an equally large trough of low pressure over the interior west. This will result in a northerly flow with below average temperatures. The storm track is well north so precipitation is unlikely.
January: This model is rather inconclusive on precipitation and temperature trends. If anything, precipitation will be close to average with temperatures that are marginally above average. It does appear there will be potentially extended periods of dry weather, leading to episodes of fog and low clouds from time to time.
February, March, April: If this model has any kind of a grip on the situation, temperatures will run somewhat above average during the late winter/early spring period. This model would really dash the hopes of a wet winter as it does indicate below average rain for the three month period.
Winds Discussion: Winds will generally be at or less than 6 MPH with periods of near calm conditions through Saturday.
Rain Discussion: The only chance of rain for the next week to possibly ten days will be late Sunday and Sunday night, possibly into early Monday. A cold front will move rapidly down the valley. However, models continue to show this system to be moisture starved, so most if not all the precipitation will be confined to the Sierra Nevada with just a small chance of a few light showers on the valley floor.
Frost Discussion: Short term, we will have no problems with frost through Sunday morning. for several days, we’ve been discussing the potential of a cold weather episode beginning Monday. Some models show this air mass invading central California Sunday, especially during the late afternoon to overnight hours. The GFSX model guidance is advertising a low of 32 Monday, 30 Tuesday, and 33 Wednesday. other models are also indicating below freezing temperatures, especially for Tuesday and Wednesday. if this model information is accurate, coldest unprotected locations could drop down into the 26 to 28 degree category as early as Monday morning with a greater risk Monday and Tuesday morning.
With some luck, we could see some upslope clouds Monday, but this is shaping up to be a dry air mass, so that possibility is unlikely.
The pattern guiding me to some of these conclusions shows a massive upper high over the eastern Pacific with a very cold trough of low pressure over the interior west, just to the east of the Sierra Nevada. The coldest air will be over Nevada and points east. Even so, models are showing a distinct northerly flow aloft from the Yukon Territory southward into California the first half of next week.
Afternoon Dew Points Today: Mid to upper 40s. Kern: Mid to upper 40s. Humidity values ranging from 65%/100% at Hanford. Bakersfield 55%/95%
Actual Humidity range January 28, 2020: Delano, 100%/65% Porterville, 99%/57%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 50%, tomorrow 70%. Bakersfield: Today: 30% Tomorrow: 60%
ET Rates Over the Past Seven Days: Stratford .46, Parlier .35, Blackwell Corner .40, Arvin .36, Orange Cove .32, Porterville .33, Delano .42. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 53, Parlier 52, Blackwell 53, Arvin, 52, Orange Cove 53, Porterville 53, Delano 50
Record Temperatures: 73/24. Average Temperatures: 57/36
Heating Degree Days this Season: 1321 -369
Courtesy of the NWS
Average temperature for January so far: 47.9 +2.8
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2019 Fresno: 3.53 season. or -1.90. Month to Date: .65 -1.31
Since Oct 1, 2019, Bakersfield: 2.83, or -.16. Month to Date: .23 -.79
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove 685, Parlier 757, Arvin 581, Shafter 666, Stratford 657, Delano 740, Lindcove 866, Porterville 1170
Hours at 45 or below 45.
Sunrise: 7:03 Sunset: 5:22 pm. Hours of Daylight: 10:17
Yesterday’s Weather:
MCE : Merced 153 : DH1600 / 64 / 42 / 0.00 /
MAE : Madera 253 : DH1600 / 62 / 41 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 62 / 42 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 63 / 38 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 62 / 36 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 60 / 39 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 61 / 37 / 0.00 /
ATEC1 : Avenal 787 : DH0613 / M / M / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 62 / 37 / 0.00 /
TFTC1 : Taft 759 : DH1551 / 59 / 46 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 65 / 44 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr season % last year % Ave. 365 day ave.
STOCKTON 0.00 5.27 73 7.91 110 7.18 14.06
MODESTO 0.00 3.92 61 6.35 99 6.42 13.11
MERCED 0.00 5.69 95 6.12 103 5.96 12.50
MADERA 0.00 2.90 48 4.58 76 6.03 12.02
FRESNO 0.00 3.54 65 4.42 81 5.44 11.50
HANFORD 0.00 3.12 62 3.33 66 5.05 10.10
BAKERSFIELD 0.00 2.83 95 2.27 76 2.99 6.47
BISHOP 0.00 1.16 45 3.46 134 2.59 5.18
SALINAS T 5.99 96 5.80 93 6.24 12.83
PASO ROBLES 0.00 6.61 108 6.36 104 6.13 12.78
SANTA MARIA 0.00 4.79 74 6.41 99 6.50 13.95
Next report: January 29/afternoon