December 30, 2018
Summary: Temperatures this morning are as cold to a degree or two warmer in some locations as they were yesterday. More below in the frost section.
We have a rapidly evolving weather pattern. A cold low is dropping southeastward from British Columbia into the Pacific Northwest. The leading edge of this low has already reached southern Oregon and southern Idaho. It will dig into the Great Basin Monday. As the low drops into Arizona, initially a north to south flow will develop into California and by New Year’s Eve night and New Year’s Day, the upper winds will be out of the north/northeast. By Monday night, a relatively strong surface high will center over Wyoming and Utah, creating a relatively strong off shore flow. The combination of all these factors will inject another burst of cold and, more importantly, dry air into the San Joaquin Valley.
On Tuesday, but more especially Wednesday and Thursday, we’ll see temperatures back down into the mid to upper 20s with a slight chance of lower 20s in those traditional cold pockets. The good news is, a flat zone of upper level high pressure will develop across the eastern Pacific, extending its reach into the western United States. This, in turn, creates a westerly flow, bringing much milder air in above the valley floor and eventually slow moderation in overnight low temperatures.
For the fourth day in a row, the model consensus says precipitation could return to central California this coming weekend. Some show a slug of subtropical moisture moving into southern California and possibly into central California. At the same time, a trough of low pressure will be streaming into northern and central California, so I feel comfortable adding at least a chance of rain to the forecast, mostly likely late Saturday and Sunday.
Forecast: Other than occasional high clouds, it will be mostly clear through tonight. Mostly clear to occasionally partly cloudy New Year’s Eve through New Year’s Day. Mostly clear Tuesday night through Friday. Increasing cloudiness Friday night leading to a chance of rain late Saturday through Sunday.
Short Term:
| Madera 55/29/52/27/51 | Reedley 54/29/52/27/51 | Dinuba 53/28/51/27/50 | |
| Porterville 56/29/53/27/52 | Lindsay 56/28/51/26/50 | Delano 56/30/51/29/51 | |
| Bakersfield 56/35/55/33/52 | Taft 56/38/53/32/51 | Arvin 56/30/53/28/51 | |
| Lamont 57/30/52/29/52 | Pixley 55/29/51/27/50 | Tulare 54/28/52/27/50 | |
| Woodlake 55/29/53/28/51 | Hanford 56/31/53/28/51 | Orosi 54/29/53/28/51 | |
Seven Day Forecast:
| Wednesday
Mostly clear 26/52 |
Thursday
Mostly clear 27/55 |
Friday
Mostly clear 31/59 |
Saturday
PM rain possible 44/59 |
Sunday
Chance of rain 44/57 |
Two Week Outlook: January 6 through January 12: This model indicates a higher potential for rain during this time frame. It’s possible lower latitude storms could affect the area. With generally a westerly flow, expect temperatures to run above average.
January: This model shows generally above average temperatures for January over the western one-third of the United States while near to below average temperatures will prevail east of the Rockies. There is no firm indicator of really above or below average precipitation although it does forecast below average rain in the Pacific Northwest.
January, February, March: The western half of the United States is projected in a very general sense to have above average temperatures for the next 90 days. Like the 30 day outlook, it seems to want to project near average precipitation, which would be nice.
Winds: Winds will be at or less than 6 MPH with periods of near calm conditions through tonight. Winds Monday along the west side will increase out of the northwest at 15 to 25 MPH with stronger gusts, especially along the Interstate 5 corridor. Elsewhere, winds will be generally along the northwest at about 5 to 15 MPH with stronger gusts from Fresno County northward. Winds Monday night and Tuesday along the far west side will be out of the north 10 to 20 MPH with stronger gusts. Winds elsewhere will be generally variable at 5 to 15 mph with periods of near calm conditions Monday night. winds Wednesday will be generally less than 8 MPH with periods of near calm conditions.
Rain: Expect dry weather through at least Friday night. For the fourth day in a row, some models are pointing to a chance of rain over the weekend next weekend. Some models show a slug of subtropical moisture possibly moving into the southern half of California while a trough of low pressure moves through northern and central California about the same time. This far out, I’m comfortable just using the word “chance” as much could change, and usually does.
Frost Discussion: As of 6:30am, Navelencia, Exeter, west Porterville, and Maricopa were reporting 27 degrees while most other locations were between 28 and 31. Temperatures this morning are running a degree or two warmer than there were yesterday, especially in the south valley. We should see minor modification tonight due to possible mixing ahead of a very cold low currently moving into the Pacific Northwest which will rapidly move into the Great Basin Monday and into Arizona Monday night and Tuesday. Winds wrapping around the back side of this system will be out of the north over California with a reasonably good chance another surge of modified arctic air will move into the valley. Mid to upper 20s are likely again Monday and more especially Tuesday through Thursday. The potential of this air mass will again depend upon how much of this moderately colder and drier air mass ultimately settles in. for now, I’m just going with widespread mid to upper 20s again with an outside chance of lower 20s in the traditional cold unprotected pockets.
The good news is that this pattern will not last long. By Wednesday, a flat zone of upper level high pr essure will form across the Pacific and extend into the western United States. This will generate a westerly flow, meaning much milder air aloft will begin to move in as early as Wednesday night and Thursday, ultimately mixing down and bringing those overnight lows up.
Above freezing conditions can be expected Friday and beyond.
Lows Tonight:
| Terra Bella
29 |
Porterville
29 |
Ivanhoe
28 |
Woodlake
29 |
| Strathmore
29 |
McFarland
28 |
Ducor
30 |
Tea Pot Dome
29 |
| Lindsay
28 |
Exeter
28 |
Famoso
29 |
Madera
29 |
| Belridge
28 |
Delano
30 |
North Bakersfield
31 |
Orosi
28 |
| Orange Cove
29 |
Lindcove
28 |
Lindcove Hillside
34 |
Sanger River Bottom
27 |
| Root Creek
28 |
Venice Hill
29 |
Rosedale
31 |
Jasmine
30 |
| Arvin
31 |
Lamont
30 |
Plainview
29 |
Mettler
Af |
| Edison
32 |
Maricopa
28 |
Holland Creek
33 |
Tivy Valley
30 |
| Kite Road South
32 |
Kite Road North
29 |
AF=Above Freezing
Afternoon Dew Points Today: Mid to upper 30s. Kern: Mid to upper 30s.
Humidity: Porterville: 60%/95%, Bakersfield: 55%/90%
Actual Humidity December 29, 2018: Delano, 97%/44% Porterville, NA
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 90%, tomorrow 70% Bakersfield: Today: 90% Tomorrow: 80%
ET Rates Over the Past Seven Days: Stratford .32, Parlier .24, Blackwell .33, Lindcove .20, Arvin .31, Orange Cove .23, Porterville .NA, Delano .28 Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 54, Parlier 52, Blackwell 53, Lindcove, 58, Arvin, 52, Orange Cove 56, Porterville NA, Delano 50
Record Temperatures: 67/24. Average Temperatures: 53/35
Heating Degree Days this Season: 778 -304
Courtesy of the NWS
Average temperature for December so far: 49.1 +4.4
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 2.33 season. or -1.00, Month to Date: .56 -1.07
Since Oct 1, 2018, Bakersfield: 1.30, or -.58. Month to Date: .62 -.32
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, 355, Parlier, 384 , Arvin, 312 Shafter, 404 Stratford, 366, Delano 378, Lindcove, 567, Porterville, 747
. Hours at 45 or below 45.
Sunrise: 7:11 am Sunset: 4:53 pm. Hours of Daylight: 9:42
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 57 / 33 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 55 / 34 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 55 / 29 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 55 / 27 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 56 / 31 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 54 / 29 / M /
ATEC1 : Avenal 787 : DH1557 / 56 / 28 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 57 / 29 / 0.00 /
TFTC1 : Taft 759 : DH1550 / 52 / 35 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr Season % L.Y. % Ave. Ave. yearly total
STOCKTON 0.00 5.88 128 0.96 21 4.58 14.06
MODESTO 0.00 4.49 114 1.03 26 3.93 13.11
MERCED 0.00 3.87 115 1.11 33 3.37 12.50
MADERA 0.00 2.99 83 0.41 11 3.60 12.02
FRESNO 0.00 2.33 70 0.41 12 3.33 11.50
HANFORD 0.00 1.87 63 0.41 14 2.96 10.10
BAKERSFIELD 0.00 1.30 69 0.07 4 1.88 6.47
BISHOP 0.00 1.57 101 0.16 10 1.55 5.18
SALINAS 0.00 4.77 127 0.78 21 3.77 12.83
PASO ROBLES 0.00 3.60 103 0.27 8 3.49 12.78
SANTA MARIA 0.00 2.74 70 0.12 3 3.89 13.95
Next report: Sunday afternoon/December 30