May 25, 2018
Summary: The center of circulation of a cold closed low is just to the west of San Francisco at this hour. The first phase of this event saw a strong surge of marine air move over the coastal mountains, forming a low overcast over the entire San Joaquin Valley during the early morning hours. Meanwhile, above that low cloud deck, clouds are increasing with even a few light showers showing up from Fresno County northward. The low will track right across central California today, giving an increasing threat of scattered showers and isolated thunderstorms. The pool of cold air associated with this system is quite cold considering we’re pushing June. Numerous showers and scattered thunderstorms will become apparent over the Sierra Nevada. Freezing levels will drop to 9,500 to 10,000 feet, resulting in snow possibly as low as 8,000 feet. A great weekend to go camping!
The best dynamics of this storm will be from Fresno County northward, however the chance of active weather will cover the entire area today and tonight. By Sunday morning, the low will have slowly moved into western Nevada, ending the chance of showers on the valley floor, but that chance will continue over the Sierra Nevada.
As you might expect, temperatures today will plummet with some locations struggling into the lower 70s and perhaps mid 70s Saturday. The turn around day will be Sunday as upper level high pressure begins to move in from the west as the low is ejected into Utah. That high will dominate the pattern through Tuesday night with much warmer conditions. Temperatures may reach the 90 degree mark as early as Monday. The high, as has been the pattern this month, will be short lived. A new trough of low pressure will move in from the eastern Pacific Wednesday and Thursday. No active weather will be associated with this trough. The main energy will be over the Pacific Northwest, however temperatures will again cool to near to possibly even below average by Thursday. Nothing too exciting longer term as dry weather continues along with seasonal conditions.
Forecast: Mostly cloudy through Saturday with a chance of scattered showers and isolated thunderstorms through early Saturday morning. Partly cloudy Saturday night. Becoming mostly clear and warmer Sunday through Tuesday. Mostly clear and a bit cooler Wednesday through Friday.
Short Term:
| Madera 70/54/75/54/83 | Reedley 71/55/77/55/84 | Dinuba 70/53/77/54/83 | |
| Porterville 70/55/75/55/84 | Lindsay 70/54/76/54/84 | Delano 72/56/77/56/85 | |
| Bakersfield 73/58/75/58/84 | Arvin 71/58/75/58/84 | Taft 73/59/75/59/83 | |
| Lamont 73/57/75/58/83 | Pixley 71/54/76/55/83 | Tulare 70/54/75/55/83 | |
| Woodlake 72/54/77/55/85 | Hanford 70/55/77/56/85 | Orosi 72/53/77/55/83 | |
Seven Day Forecast:
| Monday
Mostly clear 60/90 |
Tuesday
Mostly clear 63/95 |
Wednesday
Mostly clear 63/90 |
Thursday
Mostly clear 55/84 |
Friday
Mostly clear 54/82 |
Two Week Outlook: May 31 through June 6: This model shows a trough of low pressure moving into the western states and remaining for a few days. No precipitation would be expected with this pattern, however temperatures would lower to near seasonal values.
June: As we head into the summer months, it appears this June will be mostly dry, as is typical. Models are projecting higher than average pressure patterns during the month so look for temperatures, generally speaking, to be above average.
June, July, August: All summers are hot in the San Joaquin Valley, and typically very dry. This summer will be no exception. If there’s any tendency on modeling at all it would be that upper level high pressure would be marginally stronger than average with temperatures also running marginally above average. The monsoon season will begin in several weeks so it’s impossible to tell it will be an active one this year. We’ll just have to wait and see.
Winds: Winds through Saturday will be out of the northwest at 10 to 20 MPH with local gusts to 30 MPH, mainly in western Fresno and Kings Counties. Winds Saturday night through Monday will generally be less than 15 MPH.
Rain: Already this morning, a few light showers developed over Fresno and Madera Counties. The center of the cold upper low is just to the west of San Francisco and will drag slowly eastward across our area through tonight. As it does, the chance of scattered showers and isolated thunderstorms will increase, especially from Fresno County north. However, the risk factor can be considered to be just about anywhere. I would put the chance of measurable rain from Fresno County north at roughly 50%, perhaps a little less south of that line. Rainfall amounts, where it does rain, will be generally less than .10, but if isolated thunderstorms occur, a quarter inch or more could occur in isolated pockets. By early Saturday morning, the low will have moved into Nevada, so Saturday will be dry after a small chance of early morning showers occurs over the foothills. Dry weather will continue Saturday night and then for the foreseeable future.
Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: Upper 40s to the lower 50s.
Humidity: Visalia: 45%/85% Bakersfield: 40%/75%
Actual Humidity May 23, 2018: Delano, 84%/33%, Porterville, 82%/32%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 20% tomorrow 60% Bakersfield: Today: 30% Tomorrow: 70%
ET Rates Over the Past Seven Days May 23, 2018: Stratford 1.84, Parlier 1.65, Blackwell 1.97, Lindcove 1.59, Arvin 1.88, Orange Cove 1.79, Porterville 1.61, Delano 1.62, Madera Two 1.69. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 70, Parlier 71, Blackwell 77, Lindcove, 70, Arvin, 81, Orange Cove 66, Porterville 79, Delano 76, Madera Two, 78
Record Temperatures: 103/41. Average Temperatures: 86/56
Cooling Degree Days this Season: 193 +57 Courtesy of the NWS
Average temperatures for May so far, 69.8 +1.9
Precipitation: Seasonal total/average/above or below average:
Since July 1, 2017 Fresno: 6.73 season. or -4.28. Month to Date: .00
Since July 1, 2017, Bakersfield: 3.93, or -2.31. Month to Date: T
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, Parlier, Arvin, Shafter, Stratford, Madera two, Lindcove, Porterville, Hours at 45 or below 45.
Sunrise: 5:45 am Sunset: 8:08 pm. Hours of Daylight: 14:21
Yesterday’s Weather:
MAE : Madera 253 : DH1700 / 80 / 54 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 83 / 56 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 83 / 57 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 82 / 53 / 0.00 /
BFL : Bakersfield Airport 496 : DH1700 / 83 / 59 / 0.00 /
VIS : Visalia Airport 292 : DH1700 / 81 / 56 / 0.00 /
ATEC1 : Avenal 787 : DH1646 / 79 / 56 / 0.00 /
PTV : Porterville Airport 442 : DH1700 / 82 / 55 / 0.00 /
TFTC1 : Taft 759 : DH1655 / 80 / 60 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 74 / 58 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
Year % Last Y. % Ave. Annual ave.
STOCKTON 0.00 9.09 67 21.68 160 13.59 14.06
MODESTO 0.00 8.00 63 16.79 133 12.60 13.11
MERCED 0.00 6.91 58 15.79 132 12.00 12.50
MADERA 0.00 7.22 63 14.17 123 11.50 12.02
FRESNO 0.00 6.73 61 17.20 156 11.02 11.50
HANFORD 0.00 4.70 49 11.04 114 9.67 10.10
BAKERSFIELD 0.00 3.93 63 7.81 125 6.24 6.47
BISHOP 0.00 1.47 33 9.16 206 4.45 5.18
SALINAS 0.00 7.13 57 16.36 131 12.48 12.83
PASO ROBLES 0.00 9.62 78 16.14 130 12.40 12.78
SANTA MARIA 0.00 6.01 44 18.44 135 13.69 13.95
Next report: Saturday, May 26