February 28, 2019
Summary: The valley is largely clear of shower activity at this hour with a few exceptions. Over the Sierra Nevada, light showers continue. We will remain under a moist, westerly flow aloft today. The amount of moisture is significant, however there’s no real trigger at this time to generate much shower activity so what showers there are today will be generally widely scattered. Showers will continue over the Sierra Nevada due to that westerly flow being forced upward orographically.
The air mass remains quite mild with the freezing level over Oakland last night right at 7,000 feet. Further south at Vandenberg, the freezing level jumps up to 8,700 feet. Satellite imagery over the Pacific clearly depicts a lower latitude storm with a mass of subtropical moisture moving into its southeastern side. That low will race across the Pacific and into northern and central California Friday night through Saturday night. this will not be a blockbuster storm. However, it will add another inch or two of rain in the foothills and mountains and possibly as much as .50 on the valley floor, generally from northern Tulare County north with considerably less along the west side and in Kern County due to the usual rain shadows.
Showers will continue for a time Sunday behind the exiting low. Another very temporary ridge of high pressure will then move in from the west for dry weather late Sunday through Monday. Clouds will begin to increase Monday night then one of the strongest systems we’ve seen this winter will arrive just in time for meteorological spring to begin. Models have been amazingly consistent on this system and they all indicate it will be a very large system and will have a significant pineapple connection. Models paint this atmospheric river of air right into central California Tuesday for potentially extremely heavy precipitation, especially in the Sierra Nevada and to a lesser extent the Kern County mountains. This AR feed will move slowly into southern California Wednesday for heavy rain over the southland.
Models beyond Wednesday mix things up a bit in trying to nail down a particular pattern. Overall, however, a broad area of low pressure is projected to cover the eastern Pacific, allowing for additional activity to move into central California, possibly around a week from Saturday. For now, though, with model differences, that’s pretty much conjecture on my part.
Forecast: Variable cloudiness through Friday with a chance of widely scattered showers today. The chance of rain will increase Friday night, continuing at times Saturday through Saturday night. showers Sunday morning with a chance of showers Sunday afternoon. Mostly to partly cloudy Sunday night and Monday. Increasing cloudiness Monday night with an increasing chance of rain. Rain, heavy at times, Tuesday and Tuesday night with showers Wednesday and Wednesday night. a chance of showers Thursday.
Short Term:
| Madera 67/50/65/54/65 | Reedley 66/50/65/54/65 | Dinuba 65/50/64/53/64 | |
| Porterville 67/50/66/54/67 | Lindsay 67/49/65/54/66 | Delano 67/52/65/53/67 | |
| Bakersfield 70/53/67/55/68 | Taft 69/54/67/55/68 | Arvin 70/52/67/55/69 | |
| Lamont 69/52/67/55/68 | Pixley 67/50/65/54/65 | Tulare 65/49/65/53/65 | |
| Woodlake 67/50/64/53/65 | Hanford 67/51/65/55/66 | Orosi 66/50/65/53/66 | |
Seven Day Forecast:
| Sunday
AM showers 54/68 |
Monday
Partly cloudy 49/64 |
Tuesday
Heavy rain 51/65 |
Wednesday
Rain likely 51/66 |
Thursday
Chance of showers 46/65 |
Two Week Outlook: March 6 through March 12: The storm door will remain open during this time frame, but a fundamental change does occur. Potential storm systems will originate in the Gulf of Alaska, meaning temperatures will likely be below average with lower snow levels along the Sierra Nevada.
March: February is a classic example of the unreliability of long range weather forecasting. The 30 day outlook for February was for above average temperatures and drier than normal conditions. Can you say “Ooops”? anyway, the 30 day out look for March gives us marginally above average temperatures with equal chances of above or below precipitation (so in other words, flip a coin).
February, March, April: At least this model projects about equal chances for either above or below average precipitation. There is actually a greater possibility of below average rain over the Pacific Northwest. Generally speaking, temperatures should remain at least marginally above average.
Winds: Winds will be variable today at 5 to 12 MPH. Winds tonight and Friday will remain variable, generally at or less than 10 MPH with periods of near calm conditions. Winds later Friday night through Sunday will be generally out of the southeast at 15 to 25 MPH from Fresno County north and along the west side. In Kern County, winds will be out of the east to southeast at 10 to 20 MPH with local gusts to 40 MPH possible near the base of the Tehachapi Mountains. In Tulare County, winds Friday night through Sunday will be generally out of the east to southeast at 10 to 15 MPH with locally stronger gusts.
Rain: Generally widely scattered showers can be expected for the remainder of the day with amounts generally less than .10 with many areas probably receiving no more than a trace. A very temporary dry slot will set up tonight and last through Friday then precipitation will again spread in from the west/southwest Friday night, continuing on and off through Saturday night. rain will taper off into showers Sunday morning. Rainfall amounts along the east side of the valley from northern Tulare County up through Madera County could approach .50 with locally more with generally about .33 down into southeastern Tulare County. Rain shadows along the west side and in Kern County will definitely be a factor with this storm. Possibly .10 to .25 could occur over the valley portion of Kern County and around .25 along the west side.
Dry weather will return Sunday afternoon through Monday. After that, one of the wettest storms of the winter will arrive Monday night and continuing through Wednesday. On paper, this system will have all the necessary dynamics for a huge rain event, especially along the Sierra Nevada. As the low approaches, it will have plenty of cold air feeding in from the Gulf of Alaska and a significant pineapple connection which current models show moving right into central California Tuesday and Tuesday night then down into southern California Wednesday. Normally I don’t like to take a shot at precipitation amounts this far out, but in instances in the past with similar characteristics, 5 to 10 inches of rain have fallen over the Sierras from the Kern County line north.
Frost Discussion: All locations will be above freezing for the foreseeable future.
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Afternoon Dew Points Today: Low to mid 50s. Low to mid 50s. Humidity values ranging from 55%/90% at Hanford. Bakersfield 45%/90%
Actual Humidity February 27, 2019: Delano, NA Porterville, 93%/47%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 50%, tomorrow 30% Bakersfield: Today: 50% Tomorrow: 30%
ET Rates Over the Past Seven Days: Stratford .61, Parlier .63, Blackwell .59, Lindcove .57, Arvin 62, Orange Cove .59, Porterville .59, Delano .NA Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 52, Parlier 51, Blackwell 50, Lindcove, 54, Arvin, 50, Orange Cove 49, Porterville 51, Delano NA
Record Temperatures: 79/28. Average Temperatures: 65/42
Heating Degree Days this Season: 1732 -410
Courtesy of the NWS
Average temperature for February so far: 47.9 -2.3
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 7.82 season. or +.20. Month to Date: 3.26 +1.30
Since Oct 1, 2018, Bakersfield: 3.88, or -.44. Month to Date: 1.20 -.00
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, 878, Parlier, 845 , Arvin, 804 Shafter, 848 Stratford, 846, Lindcove, 1179, Porterville, 1647
Hours at 45 or below 45.
Sunrise: 6:30 am Sunset: 5:53 pm. Hours of Daylight: 11:21
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 70 / 54 / 0.25 /
FAT : Fresno Airport 333 : DH1600 / 68 / 53 / 0.03 /
HJO : Hanford Airport 242 : DH1600 / 66 / 50 / 0.02 /
NLC : Lemoore Naval AS 234 : DH1600 / 65 / 50 / 0.04 /
BFL : Bakersfield Airport 496 : DH1600 / 69 / 48 / 0.01 /
VIS : Visalia Airport 292 : DH1600 / 66 / 52 / T /
ATEC1 : Avenal 787 : DH1554 / 58 / 48 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 71 / 51 / T /
TFTC1 : Taft 759 : DH1553 / 62 / 49 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / 63 / 52 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr Season % L.Y. % Ave. Ave. yearly total
STOCKTON 0.05 12.74 128 4.96 50 9.93 14.06
MODESTO 0.04 9.32 104 3.75 42 8.99 13.11
MERCED 0.06 9.54 114 2.58 31 8.37 12.50
MADERA 0.25 7.57 92 1.76 21 8.23 12.02
FRESNO 0.03 7.82 103 1.90 25 7.62 11.50
HANFORD 0.04 5.99 88 2.08 30 6.84 10.10
BAKERSFIELD 0.01 3.76 87 1.32 31 4.32 6.47
BISHOP 0.00 5.63 161 0.20 6 3.49 5.18
SALINAS 0.03 10.46 117 2.64 30 8.92 12.83
PASO ROBLES 0.35 11.67 131 2.66 30 8.91 12.78
SANTA MARIA 0.15 11.12 115 2.16 22 9.69 13.95
Next report: Thursday afternoon/February 28