May 18, 2020
Summary: The center of circulation of a deep cold core low is just west of Eureka this morning. the freezing level above Oakland taken a couple of hours ago was down to 7,000 feet. A cold front moved through the valley overnight and is now moving into southern California. Doppler radar is showing various areas of precipitation. The low will continue to move southeastward and will be directly above central California this evening. Even though the coldest and most unstable portion of this system will be overhead during the overnight hours, the combination of very strong heating with the high sun angle this time of year and cold air moving in aloft will be enough to trigger more showers and isolated thunderstorms this afternoon and evening. The showers will decrease somewhat tonight as the warming effect of the daylight hours wanes.
Tuesday will be a tricky call as the main parent low moves into Nevada and the back side of the system hangs back over central California. Most of the action will be over the Sierra Nevada, but I wouldn’t be surprised to see scattered showers and a few thunderstorms break out Tuesday afternoon through the early evening hours. By Thursday, the low will have moved into Montana and Wyoming while a new low moves into the Pacific Northwest. Unlike the previous storm, however, this system will thrust eastward so dry weather can be expected Wednesday and beyond.
Pressure patterns for the late part of the workweek through the weekend and well into next week will be fairly weak, so don’t expect dramatic warming. Temperatures will recover but only to near average.
Forecast: Scattered showers today and tonight. isolated thunderstorms will be possible this afternoon and evening. Localized heavy rain and small hail will be associated with any thunderstorm development. A chance of showers Tuesday morning with a lesser chance Tuesday afternoon. Isolated thunderstorms will again be possible Tuesday afternoon and evening. Mostly to partly cloudy Tuesday night and Wednesday morning. mostly clear to occasionally partly cloudy Wednesday afternoon and on through Monday of next week.
Short Term:
| Madera 74/48/73/47/79 | Reedley 74/47/72/47/80 | Dinuba 73/47/72/46/78 | |
| Porterville 74/47/73/46/79 | Lindsay 74/46/73/45/79 | Delano 75/49/73/48/80 | |
| Bakersfield 76/54/72/53/80 | Taft 73/55/72/54/78 | Arvin 75/51/72/52/80 | |
| Lamont 75/53/72/52/79 | Pixley 75/48/73/47/80 | Tulare 73/47/72/46/79 | |
| Woodlake 73/47/72/46/78 | Hanford 74/49/73/48/80 | Orosi 73/47/72/46/78 | |
Seven Day Forecast:
| Thursday
Mostly clear 51/85 |
Friday
Mostly clear 52/87 |
Saturday
Mostly clear 52/87 |
Sunday
Mostly clear 53/88 |
Monday
Mostly clear 52/86 |
Two Week Outlook: May 25 through May 31: This model is reverting back to more of a high pressure regime over our region with generally above average temperatures during this period. The chance of rain appears very low.
May: The first month of the dry season will be typically dry, in other words this model is portraying near average precipitation for the month of May. It also appears the trend of above average temperatures will continue for the month.
May, June, July: Obviously, over the next 90 days precipitation will be largely nonexistent with the usual few exceptions, mainly during the month of May. Models show the western half of the U.S. having generally above average temperatures.
Winds Discussion: Winds will be mainly out of the northwest at 8 to 15 MPH at time through tonight with gusts to 25 MPH, mainly near showers. Winds Tuesday will be variable to 15 MPH. Winds Tuesday night through Thursday will be generally at or less than 15 MPH afternoons and evenings and mainly out of the northwest. Winds during the night and early morning hours will be variable to around 8 MPH with periods of near calm conditions.
Rain Discussion: The following are rainfall amounts as of 6:30am. Bakersfield and Lamont .01, Buttonwillow .03, Porterville .04, Exeter .11, Tulare .13, Visalia .18, Reedley and Fresno .08, Madera .07.
Even though rainfall amounts on the valley floor have been very light, the mountain areas have been the recipients of heavy precipitation. Yosemite Valley has tallied .89, Dinky Creek 1,50, Shaver 1.08, and Wawona 1.32 with lighter amounts further south. The precipitation pattern will be quite spotty for the remainder of this event. Rainfall amounts will range from just a few hundredths to upwards of .25. If thunderstorms occur, isolated pockets could receive more than .50. most of the action will occur through tonight, especially this afternoon and evening. I do want to keep a chance of showers in the forecast for Tuesday, as well, especially along the east side of the valley even though the most active portion of this storm will have moved into Nevada. Isolated thunderstorms will be possible again Tuesday afternoon through the early evening hours. Dry weather will return Tuesday night and will continue through the weekend. Currently, nothing is showing up on models that would indicate more rain in the near and medium terms.
Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: Upper 40s to the lower 50s. Humidity values ranging from 50%/90% at Hanford. Bakersfield 40%/85%
Actual Humidity range May 17, 2020: Delano, 74%/30%, Porterville, 86%/23%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 20%, tomorrow 40%. Bakersfield: Today: 20% Tomorrow: 50%
ET Rates Over the Past Seven Days: Stratford NA, Parlier 1.72, Blackwell Corner 1.86, Arvin 1.80, Orange Cove NA, Porterville 1.69, Delano 1.78. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford NA, Parlier 72, Blackwell 76, Arvin, 72, Orange Cove NA, Porterville 78, Delano 76
Record Temperatures: 103/42. Average Temperatures: 85/54
Cooling Degree Days this Season: 162 +61
Courtesy of the NWS
Average temperature for May so far: 70.1 +2.9
Precipitation: Seasonal total for Fresno/average + or 7.52 or -3.43. Month to Date: .01 -.27
Since Oct 1, 2019, Bakersfield: 7.03, or +.82. Month to Date: .01 -.11
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: 5:48, Sunset: 8:03 pm. Hours of Daylight: 14:14
Yesterday’s Weather:
MCE : Merced 153 : DH1700 / 83 / 59 / 0.00 /
MAE : Madera 253 : DH1700 / 86 / 55 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 86 / 61 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 86 / 54 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 87 / 53 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 89 / 58 / 0.00
VIS : Visalia Airport 292 : DH1600 / 86 / 55 / 0.00 /
ATEC1 : Avenal 787 : DH1600 / 81 / 55 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 87 / 53 / 0.00 /
TFTC1 : Taft 759 : DH1650 / 85 / 60 / 0.00 /
Rainfall: 24hr W.Y. % Last Y. % Ave. Year ave.
STOCKTON 0.06 8.05 60 16.75 124 13.49 14.06
MODESTO T 6.86 55 12.76 102 12.48 13.11
MERCED T 9.34 78 12.43 104 11.91 12.50
MADERA 0.00 5.81 51 10.45 91 11.44 12.02
FRESNO 0.00 7.51 69 10.31 94 10.95 11.50
HANFORD 0.00 6.51 68 8.02 84 9.60 10.10
BAKERSFIELD 0.00 7.03 113 6.56 106 6.21 6.47
BISHOP 0.00 2.25 51 8.37 190 4.40 5.18
SALINAS T 9.06 73 12.86 104 12.42 12.83
PASO ROBLES 0.00 11.34 92 14.32 116 12.36 12.78
SANTA MARIA 0.00 10.42 76 15.05 110 13.64 13.
Next report: May 19/morning