May 17, 2019
Summary: After a day of widespread showers and thunderstorms, it’s time for the weather to settle down, if only for a short period. The center of circulation from yesterday’s event is now in southcentral Nevada and is moving eastward. The freezing level over Oakland last night was down to 6,000 feet. Vandenberg reported a freezing level of 7,000 feet. This certainly shows up nicely at Tehachapi and Sandberg where temperatures are 37 degrees at the 4,000 foot elevation with light rain and strong winds.
On the valley floor, it’s a mixed bag this morning. Some areas have relatively clear skies while others are under a low overcast. Skies will be generally partly cloudy today, becoming mostly clear tonight into early Saturday.
The next Pacific storm is also shaping up to be a major event for this late in the season, especially. A trough of low pressure which currently extends from the Gulf of Alaska into the western U.S. will be the catalyst for a new, robust, cold low pressure system which will begin to spread precipitation over northern California Saturday. A few showers could penetrate into north/central California Saturday afternoon, but the bulk of the precipitation will arrive Saturday evening with on and off precipitation through at least Sunday evening.
On Sunday afternoon, yet another pool of cold, unstable air will push in behind a strong cold front, setting the stage for another possible round of scattered thunderstorms Sunday afternoon and evening.
Models are still showing a broad area of low pressure over the western states and off shore Monday through Friday of next week. These models are still having trouble coming up with a definitive pattern. One suggests another possible fairly strong low spreading showers over the area Tuesday while others show any precipitation remaining over the mountain areas. For now, I feel most comfortable going with a small chance of showers each day through Thursday. There is some consensus on models that a new pattern will begin to evolve about Friday of next week. Currently, it doesn’t appear to be a strong ridge pattern, but one which would return temperatures back to seasonal averages and would put an end to this very unusual May rain pattern.
Forecast: Partly cloudy today. Mostly clear tonight and early Saturday. Increasing cloudiness Saturday morning. Cloudy Saturday afternoon with a chance of showers mainly from Fresno County north. Periods of showers Saturday night through at least Sunday evening with a chance of isolated to scattered thunderstorms again Sunday afternoon and evening. A small chance of showers later Sunday night and each day through Thursday. The greatest risk of showers will be later Monday night through Tuesday night. clearing Thursday night. mostly clear Friday.
Short Term:
| Madera 68/46/72/49/67 | Reedley 68/47/71/49/68 | Dinuba 67/45/71/48/68 | |
| Porterville 68/47/73/50/68 | Lindsay 69/46/71/50/67 | Delano 69/49/72/51/68 | |
| Bakersfield 67/52/74/55/68 | Taft 69/52/74/55/69 | Arvin 67/50/77/52/68 | |
| Lamont 68/50/74/52/69 | Pixley 69/48/72/50/67 | Tulare 68/46/71/50/67 | |
| Woodlake 68/47/72/50/67 | Hanford 68/47/73/50/67 | Orosi 68/46/71/50/68 | |
Seven Day Forecast:
| Monday
Slight chance of showers 48/68 |
Tuesday
Chance of showers 51/67 |
Wednesday
Slight chance of showers 48/76 |
Thursday
Partly cloudy 53/83 |
Friday
Mostly clear 55/85 |
Two Week Outlook: May 23 through May 29: This model predicts above average precipitation for much of the western U.S. with the main bulls eye at northern California. The risk of very late season will continue to be relatively high during this period with below average temperatures.
May: As we now enter the dry season, precipitation chances, according to this model, will be that of most Mays, in other words, near seasonal. Nothing too dramatic shows up as far as temperatures are concerned with readings near to marginally above average.
May, June, July: As we move through the late spring through mid summer, precipitation opportunities will be typical, in other words, not very high and that’s especially true for June and July. For this 90 day period, temperatures are projected to run somewhat above seasonal values.
Winds: Winds today will be mainly out of the northwest at 10 to 15 MPH with locally stronger gusts, decreasing to 5 to 8 MPH tonight. Winds Saturday will be mainly out of the southeast at 5 to 15 MPH, becoming out of the northwest later Saturday night and Sunday at 10 to 20 MPH with stronger gusts. Winds Monday will be mainly out of the northwest at 5 to 15 MPH.
Rain: Numerous locations from Madera to Kern County recorded between .33 and .75. Now, we turn our attention to the next nemesis which will arrive in the form of a strong low pressure system. This system will drive a strong cold front down the valley later Saturday night and early Sunday with widespread shower activity. It appears this next storm will be similar to yesterday’s event. A cold pool of very unstable air will move overhead during the day Sunday. Assuming that, like yesterday, there were breaks in the cloud cover, isolated to scattered thunderstorms will erupt resulting in locally heavy rain and small hail. Just as a broad brush, rainfall amounts from this upcoming system could exceed .50 in some locations with lesser amounts in other areas, especially in Kern County. Again, the main precipitation event will begin Saturday evening and last well through Sunday night. for now, I’m just going to keep a small chance of showers in the forecast each day Monday through Wednesday as a broad area of low pressure will remain over the western U.S. and off shore. There will be systems moving through this trough from time to time, but models are having a difficult time discerning where the main impact will be. For now, it looks like the best chance of precipitation will be Tuesday into Wednesday. We’ll go with dry weather at this point for Thursday and beyond as the trough of low pressure slowly fills, allowing dry weather to return. Most of the medium range models are now indicating dry weather for next weekend and the following week as well. Adopting a wait and see attitude on that.
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Afternoon Dew Points Today: Low to mid 40s. Kern: Low to mid 40s. Humidity values ranging from 40%/90% at Hanford. Bakersfield 40%/75%
Actual Humidity May 16, 2019: Delano, 99%/45% Porterville, 95%/39%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 50%, tomorrow 30% Bakersfield: Today: 40% Tomorrow: 30%
ET Rates Over the Past Seven Days: Stratford 1.27, Parlier 1.42, Blackwell 1.55, Lindcove .NA, Arvin 1.46, Orange Cove 1.40, Porterville 1.47, Delano 1.39. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 71, Parlier 71, Blackwell 75, Lindcove, NA, Arvin, 71, Orange Cove 70, Porterville 76, Delano 74
Record Temperatures: 106/44. Average Temperatures: 85/55
Cooling Degree Days this Season: 160 +64
Courtesy of the NWS
Average temperature for May so far: 68.7 +1.7
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 10.31 season. or -.62. Month to Date: .84 +.58
Since Oct 1, 2018, Bakersfield: 6.56, or +.35. Month to Date: .56 +.44
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, Parlier, Arvin, Shafter, Stratford, Lindcove, Porterville,
Hours at 45 or below 45.
Sunrise: 5:49 am Sunset: 8:02 pm. Hours of Daylight: 14:11
Yesterday’s Weather:
MAE : Madera 253 : DH1700 / 71 / 54 / 0.53 /
FAT : Fresno Airport 333 : DH1700 / 67 / 52 / 0.52 /
HJO : Hanford Airport 242 : DH1700 / 67 / 54 / 0.35 /
NLC : Lemoore Naval AS 234 : DH1700 / 66 / 54 / 0.31 /
BFL : Bakersfield Airport 496 : DHM / 68 / 54 / 0.05 /
VIS : Visalia Airport 292 : DH1700 / 67 / 53 / 0.15 /
ATEC1 : Avenal 787 : DHM / 63 / 53 / M /
PTV : Porterville Airport 442 : DH1700 / 68 / 53 / 0.11 /
TFTC1 : Taft 759 : DH1655 / 63 / 55 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 65 / 58 / 0.04 /
Rainfall: Water year Oct 1st through September 30th
24hr Season % L.Y. % Ave. Ave. yearly total
STOCKTON 0.44 16.75 124 9.09 67 13.47 14.06
MODESTO 0.08 12.24 98 8.00 64 12.46 13.11
MERCED 0.20 12.30 103 6.91 58 11.90 12.50
MADERA 0.38 10.37 91 7.22 63 11.42 12.02
FRESNO 0.46 10.01 92 6.73 62 10.93 11.50
HANFORD 0.33 8.02 84 4.70 49 9.58 10.10
BAKERSFIELD 0.05 6.37 103 3.93 63 6.21 6.47
BISHOP 0.28 8.37 190 1.25 28 4.40 5.18
SALINAS 0.14 12.83 103 7.13 57 12.41 12.83
PASO ROBLES 0.17 14.32 116 9.62 78 12.35 12.78
SANTA MARIA 0.15 15.05 110 6.01 44 13.63 13.95
Next report: Friday afternoon/May 17