March 20, 2018
Summary: Get ready, here it comes. The dynamics of this upcoming event and the water content of tropical moisture moving in from the southwest is the highest you’ll see every five to ten years. The overall pattern is for a powerful low pressure system still about 800 miles to the west of San Francisco to move slowly east/northeast. In the meantime, an atmospheric river of air stretching from nearly Hawaii to roughly 200 miles off the southern and central California coast is nicely taking shape. There will be a chance of light rain this morning as the initial scouts from this flow begin to move in from the southwest. Rain will become likely this afternoon with very heavy precipitation at times tonight through about midday Thursday.
Model information is now projecting that 5 to 10 inches of rain will fall from Santa Barbara County southward to about Los Angeles County over the mountains and that same amount is possible over the Sierra Nevada with the snow level above 8,000 feet. All of this rain will be falling on top of 5 to 10 feet of snow that fell last week. This is a recipe for tremendous run off in the rivers and streams along the west facing slopes of the Sierra.
Here on the valley floor, and I can’t remember when I’ve seen this before, with very high moisture content in the atmosphere, two inches of rain is certainly possible from this afternoon through Thursday evening, possibly even over the valley portion of Kern County. The low will eventually move inland late Thursday into early Friday, driving a cold front down the valley Thursday afternoon. That is when the precipitation pattern will become more showery.
A ridge of high pressure will finally begin to move inland Friday through Sunday for a return to dry weather. If models are accurate, next week will be dry with the two week model indicating dry weather all the way through April 2.
Forecast: Light showers this morning. Rain will spread in from the southwest this afternoon. Rain, locally heavy at times, from late this afternoon through Thursday morning. Showers Thursday afternoon and night. Mostly to partly cloudy Friday. Partly cloudy Friday night through Sunday. Mostly clear Sunday night through Tuesday.
Short Term:
Madera 67/56/67/58/67 | Reedley 67/57/66/58/67 | Dinuba 66/55/66/57/66 | |
Porterville 68/58/68/58/67 | Lindsay 67/57/65/58/66 | Delano 68/57/66/59/68 | |
Bakersfield 70/59/69/60/70 | Arvin 70/58/70/61/71 | Taft 69/60/69/61/70 | |
Lamont 69/58/69/60/70 | Pixley 68/57/66/58/67 | Tulare 65/56/66/58/67 | |
Woodlake 66/56/66/58/67 | Hanford 67/57/66/58/68 | Orosi 66/57/66/58/66 |
Seven Day Forecast:
Friday
Mostly cloudy 45/63 |
Saturday
Partly cloudy 40/61 |
Sunday
Partly cloudy 38/62 |
Monday
Mostly clear 39/67 |
Tuesday
Mostly clear 44/73 |
Two Week Outlook: March 7 through April 2: This model is persistent in showing a strong ridge of upper level high pressure building over and off the west coast. This is a dry pattern. Temperatures under this regime will range above seasonal values.
March: Not much encouragement as far as rainfall is concerned as this model is indicating below average precipitation, especially over the second half of the month. So far, this model predicts near average temperatures.
March, April, May: The ninety-day outlook doesn’t exactly make one happy if rain is the desired outcome. It does show a better than average chance of above average temperatures, mainly due to high pressure off shore, and below average precipitation.
Winds: Winds will be generally out of the southeast today at 5 to 15 mph with stronger gusts, increasing to 10 to 15 MPH tonight through Wednesday morning. Winds late Wednesday through Thursday will be out of the southeast, increasing to 15 to 30 MPH in places with gusts over 40 MPH possible in the extreme south valley. Winds Thursday night and Friday will be out of the northwest at 10 to 20 MPH with light winds returning Saturday and Sunday.
Rain: Models this morning are striking in the fact that the moisture content of an atmospheric river of air moving in from the southwest is such that it only occurs every 5 to 10 years. If this storm lives up to what I see on paper, tremendous amounts of rain will fall over the Coast Range, the Kern County mountains, and especially the Sierra Nevada which could accumulate 5 to 10 inches of rain between this afternoon and Thursday night. The moisture content is so high it will probably overcome any rain shadow effects, thus the valley floor will experience heavy rain, as well. From this afternoon through Thursday night, more than 2 inches of rain is possible, especially along the east side. Even the valley portion of Kern County could record between one and two inches before this storm is over.
A cold front will move down the valley Thursday afternoon. That is when the rain will turn more showery. Showers will continue through Thursday night. The whole mess should be moving into the interior west Friday with dry weather beginning then and lasting through the weekend and all of next week.
Frost: All locations will be above freezing for the foreseeable future.
Lows Tonight: All locations will be above 32 degrees.
Afternoon Dew Points Today: Low to mid 40s Kern: Low to mid 40s
Humidity: Visalia: 45%/95% Bakersfield: 45%/85%
Actual Humidity March 19, 2018: Delano, 91%/37%, Porterville, 98%/33%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 0% tomorrow 0% Bakersfield: Today: 0% Tomorrow: 0%
ET Rates Over the Past Seven Days March 19, 2018: Stratford .81, Parlier .61, Blackwell .82 Lindcove .66, Arvin .74, Orange Cove .66, Porterville .68, Delano .73, Madera Two .63. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 58, Parlier 57, Blackwell 59, Lindcove, 59, Arvin, 60, Orange Cove 56, Porterville 59, Delano 58, Madera Two 56
Record Temperatures: 89/33. Average Temperatures: 68/44
Heating Degree Days this Season: 1871, -480 Courtesy of the NWS
Average temperatures for March so far, 54.1 -0.6
Precipitation: Seasonal total/average/above or below average:
Since October 1, 2017 Fresno: 3.82 season. or -5.22. Month to Date: 1.92
Since October 1, 2017, Bakersfield: 2.41, or -2.76, Month to Date: .1.09
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, 952, Parlier, 977, Arvin, 851, Shafter, 1007, Stratford, 965, Madera two, 1480, Lindcove, 1105, Porterville, 1433. Hours at 45 or below 45.
Sunrise: 7:01 am Sunset: 7:12 pm. Hours of Daylight: 12:07
Yesterday’s Weather:
MAE : Madera 253 : DH1700 / 69 / 34 / 0.00 /
FAT : Fresno Airport 333 : DH1700 / 69 / 41 / 0.00 /
HJO : Hanford Airport 242 : DH1700 / 69 / 36 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1700 / 70 / 31 / 0.00 /
BFL : Bakersfield Airport 496 : DH1700 / 70 / 44 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 54 / 39 / 0.00 /
ATEC1 : Avenal 787 : DH1600 / 68 / 36 / 0.00 /
PTV : Porterville Airport 442 : DH1700 / 71 / 35 / 0.00 /
TFTC1 : Taft 759 : DH1654 / 66 / 44 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 66 / 40 / 0.00 /
Rainfall Totals:
STOCKTON 0.00 6.54 57 17.89 156 11.47 14.06
MODESTO 0.00 5.02 48 14.09 134 10.48 13.11
MERCED 0.00 4.40 44 13.51 136 9.90 12.50
MADERA 0.00 4.09 43 13.19 137 9.62 12.02
FRESNO 0.00 3.82 42 12.87 142 9.04 11.50
HANFORD 0.00 3.08 38 9.21 114 8.06 10.10
BAKERSFIELD 0.00 2.41 47 7.29 141 5.17 6.47
BISHOP 0.00 0.20 5 7.81 201 3.89 5.18
SALINAS 0.00 4.32 41 14.79 140 10.53 12.83
PASO ROBLES 0.00 5.16 48 14.63 136 10.78 12.78
SANTA MARIA 0.00 3.17 27 16.22 140 11.61 13.95
Next Report: Tuesday, March 20/PM