Summary: High clouds from a weak upper air disturbance off the southern California coast will begin to be suppressed southeastward in response to a very cold low which is now spreading showers over the Pacific Northwest. That low will drop into northern California tonight, spreading showers down the range, mainly after midnight, with a slight chance of showers over the valley floor, mainly near the Sierra Nevada foothills.
On Sunday, the trough will actually begin to form a closed low circulation, centering just off the central coast. That is where the coldest and most unstable portion of the system will reside. Even so, the center of circulation will be close to the valley tomorrow during the time of maximum daytime heating. Scattered showers will become possible tomorrow, especially from late morning through the evening hours, as the low slides southward to our west.
Models are marginal on the possibility of isolated thunderstorms. But with the higher sun angle, the daytime heating effect is more significant now, so we’ll keep a slight chance of thunderstorms in our forecast for tomorrow afternoon and evening.
By Monday morning, the low will be moving into northern Baja, ending the chance of precipitation for the remainder of next week. Dramatically cooler weather will arrive Sunday. After record highs in the low 80s yesterday, temperatures will tumble into the mid to upper 50s Sunday and only the lower 60s Monday.
Upper level high pressure just off shore will ridge inland, briefly generating a strong northeast flow both at the surface and aloft. The main challenge for Monday and Tuesday will be chilly overnight low temperatures. This is discussed below. Tranquil conditions will prevail Tuesday through Thursday evening. A low pressure system will move into the Pacific Northwest Friday night and Saturday, but for now it looks like any precipitation will remain north of central California.
Forecast: Partly cloudy today. Increasing cloudiness tonight with a slight chance of showers after midnight, mainly near the Sierra Nevada foothills. A chance of showers Sunday through Sunday evening with a slight chance of isolated thunderstorms during the afternoon and evening. Partly cloudy Sunday night, but mostly cloudy in Kern County and possibly eastern Tulare County through Monday morning. mostly clear Monday afternoon through Friday. Partly cloudy Friday night and Saturday.
Short Term:
| Madera 73/43/56/32/62 | Reedley 74/42/57/33/61 | Dinuba 73/41/55/31/61 | |
| Porterville 75/42/57/32/62 | Lindsay 75/41/57/31/61 | Delano 75/42/57/33/62 | |
| Bakersfield 76/45/56/36/61 | Taft 74/45/56/37/61 | Arvin 77/42/57/34/60 | |
| Lamont 76/42/57/34/62 | Pixley 75/43/57/32/62 | Tulare 73/41/55/31/61 | |
| Woodlake 74/42/56/31/61 | Hanford 75/43/57/33/63 | Orosi 74/41/56/30/61 | |
Seven Day Forecast:
| Tuesday
Mostly clear 33/67 |
Wednesday
Mostly clear 37/72 |
Thursday
Mostly clear 41/75 |
Friday
Partly cloudy 43/70 |
Saturday
Mostly cloudy 48/68 |
Two Week Outlook: March 7 through March 13: This model actually indicates there’s an 80% chance of above average precipitation for California during this time frame. This is just about the highest I’ve seen it this winter. Temperatures should be fairly close to seasonal averages.
March: This model does not portray a break in the dry winter we’ve experienced thus far. Generally speaking, a ridge of upper level high pressure is projected to be the primarily feature just off the central coast, resulting in above average temperatures and drier than average conditions.
March, April, May: This model indicates above average temperatures in a swath from the west coast all the way into the southwestern U.S. Precipitation is also expected to be below average from California through the Desert Southwest.
Winds Discussion: Winds will be light this morning then will begin to increase out of the west then the northwest at 15 to 25 MPH at times this afternoon through Sunday with stronger gusts, mainly along the west side. Winds Sunday night and Monday will be generally light with the exception of the far west side where there is a chance of gusty winds out of the north to northeast at 15 to 30 MPH with stronger gusts. Winds Monday night and Tuesday will be generally at or less than 10 MPH with periods of near calm conditions.
Rain Discussion: As a cold trough of low pressure dives southward over central California tonight through Sunday evening, there will be a chance of light showers. For tonight, if any showers occur at all, the risk will be mainly near the Sierra Nevada foothills. As the daytime heating process gets revved up Sunday, there will be a chance of scattered light showers. Models are marginal on the chance of isolated thunderstorms, but the parameters are such that keeping a chance of thunderstorms in the forecast for Sunday afternoon and evening is necessary. If these storms do break out, the main challenge will be brief heavy rain and small hail. Dry weather will return Sunday night and continue for the remainder of the upcoming week.
Rainfall amounts will range from nothing to generally less than .10, however if isolated thunderstorms occur, as much as .25 could be measured.
Frost Discussion: The first spring frost of the season appears fairly likely for Monday and Tuesday mornings. Currently, the pool of very cold air aloft is just west of the Washington and Oregon coastline and is dropping quickly southward. Widespread low to mid 30s are likely Monday and Tuesday mornings. River bottom and similar low spots could possibly drop to between 27 and 29 degrees. On Monday morning, behind the exiting low, the atmosphere will be quite chaotic due to a strong off shore flow, both at the surface an daloft. Upslope clouds will no doubt bank up against the valley facing slopes of the surrounding mountains. Wind conditions will also play a part, especially towards the center and west side of the valley where winds will continue for much of the night, at least in some areas. Even so, where skies clear and winds are calm, the potential of this air mass could be realized.
On Tuesday morning, even though the air aloft will be modifying, cold and dry air will be trapped on the valley floor with little in the way of cloud cover or winds to offset the chill. There will be a greater possibility of more locations dropping to or below the freezing mark. Rapid modification will occur Tuesday night and Wednesday. it’s possible river bottom and similar locations could drop into the lower 30s Wednesday morning, but most locations will remain above the freezing mark.
Above freezing temperatures will prevail the remainder of the week as a westerly flow takes over.
Afternoon Dew Points Today: Upper 30s to the lower 40s. Kern, Mid to upper 30s. Humidity values ranging from 30%/90% at Hanford. Bakersfield 25%/85%
Actual Humidity range February 28, 2020: Delano, 77%/16% Porterville, 92%/20%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 40%, tomorrow 30%. Bakersfield: Today: 30% Tomorrow: 20%
ET Rates Over the Past Seven Days: Stratford .82, Parlier .79, Blackwell Corner .90, Arvin .85, Orange Cove .80, Porterville .70, Delano .76. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 54, Parlier 56, Blackwell 55, Arvin, 57, Orange Cove 56, Porterville 55, Delano 53
Record Temperatures: 76/30. Average Temperatures: 65/41
Heating Degree Days this Season: 1721 -434
Courtesy of the NWS
Average temperature for February so far: 52.2. +1.9
Precipitation: Seasonal total/average + or – 3.54 or -4.15. Month to Date: .T. -2.03
Since Oct 1, 2019, Bakersfield: 2.84, or -1.52. Month to Date: .01 -1.23
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove 967, Parlier 1035, Arvin 831, Shafter 885, Stratford 938, Delano 1013, Lindcove 1171, Porterville 1531
Hours at 45 or below 45.
Sunrise: 6:29 Sunset: 5:54 pm. Hours of Daylight: 11:23
Yesterday’s Weather:
MCE : Merced 153 : DH1500 / 80 / 45 / 0.00 /
MAE : Madera 253 : DH1500 / 82 / 44 / 0.00 /
FAT : Fresno Airport 333 : DH1500 / 83 / 51 / 0.00 /
HJO : Hanford Airport 242 : DH1500 / 78 / 47 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 83 / 46 / 0.00 /
BFL : Bakersfield Airport 496 : DHM / 83 / 53 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 79 / 47 / 0.00 /
ATEC1 : Avenal 787 : DH1553 / 84 / 52 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 81 / 47 / 0.00 /
TFTC1 : Taft 759 : DH1551 / 83 / 50 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 79 / 51 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr season % last year % Ave. 365 day ave.
STOCKTON 0.00 5.27 53 12.76 128 9.93 14.06
MODESTO 0.00 3.92 44 9.32 104 8.99 13.11
MERCED 0.00 5.69 68 9.54 114 8.37 12.50
MADERA 0.00 2.90 35 7.57 92 8.23 12.02
FRESNO 0.00 3.54 46 7.82 103 7.62 11.50
HANFORD 0.00 3.12 46 6.01 88 6.84 10.10
BAKERSFIELD 0.00 2.84 66 3.88 90 4.32 6.47
BISHOP 0.00 1.32 38 5.63 161 3.49 5.18
SALINAS 0.00 5.99 67 10.46 117 8.92 12.83
PASO ROBLES 0.00 6.61 74 11.68 131 8.91 12.78
SANTA MARIA 0.00 4.79 49 11.14 115 9.69 13.95
Next report: February 29/afternoon