December 16, 2019
Summary: Temperatures for the first half of December have run seven and a half degrees above average. All of a sudden we get to readings in the upper 20s and low 30s and it feels cold, but actually this is more the way December is supposed to look. Strong surface high pressure is building over the Great Basin while upper level high pressure moves in from the west. We may begin to see some strong, gusty winds over portions of the valley region of Kern County Tuesday and Tuesday night. some surface models indicate a 20 to 25 millibar difference in pressure between the Great Basin and off shore San Francisco Tuesday afternoon. Locations most vulnerable will be the bottom of the Grapevine, of course, and possibly up the highway 58 corridor east/southeast of Bakersfield. North of Kern County, winds will remain light.
That low center has been on modeling information for the past week or so. It’s interesting to note the low center has been projected for several days now to be just west of San Francisco Wednesday and that is still the case this morning. it will rapidly weaken as it moves inland so there’s just a chance of light showers, mainly along the west side and from Fresno County north.
Upper level high pressure will shift eastward over California Thursday through Friday night. models for the past 10 days actually have been showing a significant trough of low pressure stretching from the Gulf of Alaska to southern California from the 21st through Christmas Eve. This far out, it’s still difficult to determine precipitation amounts, but they could potentially be pretty good, especially over the mountains.
Beginning Christmas Day, the low will shift into the Desert Southwest while upper level high pressure builds over the eastern Pacific. This is actually a piece of good news as the winds aloft will be out of the west/northwest, or generally over water, instead of the northerly or even northeasterly flows that have shown up on earlier models. Even so, for the 72 hours or so after Christmas, chilly days and frosty mornings appear likely. Some models depict more precipitation about New Year’s Eve to end the decade.
Forecast: Patchy fog this morning. otherwise it will be mostly clear. Patchy fog again tonight with high, thin clouds mixing in. partly cloudy Tuesday. Variable cloudiness Tuesday night and Wednesday with a small chance of light showers late Tuesday night and Wednesday, mainly from Fresno County northward and along the west side. There will be a chance of strong, gusty, east to southeast winds over areas of the valley portion of Kern County Tuesday and Tuesday night. partly cloudy Wednesday. mostly clear to occasionally partly cloudy Thursday through Friday night with patchy night and morning fog. Increasing cloudiness Saturday. a slight chance of showers Saturday night with an increasing chance of rain at times Sunday through Monday.
Short Term:
| Madera 54/30/55/37/57 | Reedley 55/31/56/36/57 | Dinuba 54/31/55/35/56 | |
| Porterville 56/31/56/37/58 | Lindsay 55/30/56/36/58 | Delano 56/32/58/38/59 | |
| Bakersfield 57/39/62/42/60 | Taft 57/41/59/42/59 | Arvin 57/34/59/39/60 | |
| Lamont 57/33/56/39/59 | Pixley 56/31/56/36/57 | Tulare 54/30/56/35/56 | |
| Woodlake 55/31/56/37/57 | Hanford 55/32/56/37/57 | Orosi 54/30/56/36/57 | |
Seven Day Forecast:
| Thursday
Patchy fog/partly cloudy 35/57 |
Friday
Patchy fog/mostly clear 34/55 |
Saturday
Increasing clouds 36/62 |
Sunday
Chance of rain 42/59 |
Monday
Rain likely 45/58 |
Two Week Outlook: December 23 through December 29: This model is showing a broad, cold trough of low pressure as the dominant feature with potentially cold storms moving out of the Gulf of Alaska and into California. The chance of precipitation, especially between the 22 and Christmas, is relatively high with below average temperatures.
December: NOAA always projects warmer than average temperatures during the winter months and has a fairly low batting average. This model follows suit with a projection of above average temperatures, especially over the western U.S. The latest projection for precipitation is near average rainfall will prevail.
January, February, March: This model indicates above average temperatures this winter, but what’s new, especially over the western one-third of the U.S. There are two small notations for below average precipitation. The first is over Louisiana. The second is over northern and central California. Let’s hope this projection is inaccurate, but that’s the official prognosis from NOAA.
Winds: Winds north of Kern County will be generally at or less than 7 MPH today and tonight, becoming out of the east to southeast at 5 to 12 MPH Tuesday and Tuesday night. Over the valley portion of Kern County, there is a chance of strong, gusty, east to southeast winds reaching 30 to 40 MPH near the base of the Tehachapi Mountains, possibly in excess of 50 MPH in places such as the bottom of the Grapevine and along the Highway 58 corridor east/southeast of Bakersfield. If these winds do occur, the most likely period would be Tuesday afternoon through Tuesday night as a 25 millibar difference in pressure occurs between the Great Basin and just off shore San Francisco. As the low moves inland early Wednesday, it will rapidly weaken and the winds will rapidly die off, as well. Winds Wednesday will be generally out of the southeast at 5 to 10 MPH with light winds Wednesday night through Thursday.
Rain: There will be a chance for light showers late Tuesday night and Wednesday from Fresno County northward and along the west side from Kings County north. Amounts will likely be no more than a few hundredths of an inch. Dry weather will prevail Wednesday night through Friday night and quite possibly Saturday. a significant trough of low pressure will stretch from the Gulf of Alaska to California from the 21st through the 24th. Timing the precipitation from this event is a bit challenging, but a good chance of rain will exist periodically from Sunday through next Tuesday. Precipitation amounts are unclear at this time, however significant amounts of rain and snow would not be a surprise over the Sierra Nevada. For now, some models are pointing to dry weather from Christmas Day through the 29th with possibly some precipitation at the end of the year to wind up the decade.
Frost Discussion: As of 6:00am, Navalencia and Fowler had chilled down to 29 degrees with several other locations at 30 and just about all locations are between 30 to 34 degrees. I would anticipate similar conditions tonight with the coldest, unprotected low lying regions to chill down to 27 to 29 degrees.
Satellite imagery indicates high clouds are off shore and they will move in overnight. But for now, it appears they will be too thin to really be a player. The inversion tonight will be moderate with temperatures at 34 feet from 3 to 6 degrees warmer at most locations.
I do look for all locations to be above freezing Wednesday and Thursday mornings due to cloud cover, although it is possible that, if skies clear, low 30s could occur Thursday through Saturday mornings.
During the second half of the weekend, we’ll evolve into a new pattern that will bring precipitation back to central California. Clouds and on and off precipitation between Sunday and Tuesday will keep conditions above freezing. The latest medium range models for the week between Christmas and New Year’s show dry weather up until the 29th with a chilly north/northwest flow aloft. This would lead to some frost nights, but it’s not a freeze pattern so for now it looks like nothing dangerous is on the horizon.
Lows Tonight:
| Terra Bella
31 |
Porterville
31 |
Ivanhoe
30 |
Woodlake
30 |
| Strathmore
30 |
Mcfarland
31 |
Ducor
32 |
Tea Pot Dome
31 |
| Lindsay
30 |
Exeter
29 |
Famoso
31 |
Madera
30 |
| Belridge
30 |
Delano
32 |
North Bakersfield
32 |
Orosi
30 |
| Orange Cove
31 |
Lindcove
30 |
Lindcove Hillside | Sanger River Bottom
27 |
| Root Creek
29 |
Venice Hill
30 |
Rosedale
32 |
Jasmine
31 |
| Arvin
34 |
Lamont
33 |
Plainview
31 |
Mettler
AF |
| Edison
AF |
Maricopa
AF |
Holland Creek
33 |
Tivy Valley
31 |
| Kite Road South
33 |
Kite Road North
30 |
AF=Above Freezing
Afternoon Dew Points Today: Upper 30s to the lower 40s. Kern: Mid to upper 30s. Humidity values ranging from 45%/90% at Hanford. Bakersfield 40%/30%
Actual Humidity range December 15, 2019: Delano, 100%/54% Porterville, 98%/51%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 80%, tomorrow 30%. Bakersfield: Today: 90% Tomorrow: 40%
ET Rates Over the Past Seven Days: Stratford .24, Parlier .26, Blackwell Corner .27, Arvin .NA, Orange Cove .30, Porterville .29, Delano .29. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 57, Parlier 54, Blackwell 57, Arvin, 56, Orange Cove 55, Porterville 56, Delano 51
Record Temperatures: 70/25. Average Temperatures: 54/35
Heating Degree Days this Season: 563 -230
Courtesy of the NWS
Average temperature for December so far: 52.7- +7.5
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 2.50 season. or +.09. Month to Date: 1.78 +1.07
Since Oct 1, 2018, Bakersfield: 1.61, or +.22. Month to Date: .53 +.09
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove 211, Parlier 276, Arvin 160, Shafter 201, Stratford 220, Delano 251, Lindcove 268, Porterville 421
Hours at 45 or below 45.
Sunrise: 7:05 Sunset: 4:45 pm. Hours of Daylight: 9:39
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 57 / 38 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 56 / 44 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 57 / 40 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 57 / 37 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 54 / 39 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 56 / 36 / 0.00 /
ATEC1 : Avenal 787 : DH1600 / M / M / M /
PTV : Porterville Airport 442 : DH1600 / 57 / 36 / 0.00 /
TFTC1 : Taft 759 : DH1548 / 52 / 44 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr season % last year % Ave. 365 day ave.
STOCKTON 0.00 4.05 116 3.87 111 3.48 14.06
MODESTO 0.00 2.79 96 3.05 105 2.91 13.11
MERCED 0.00 4.53 180 2.69 107 2.52 12.50
MADERA 0.00 1.91 72 2.42 91 2.66 12.02
FRESNO 0.00 2.50 104 1.92 80 2.41 11.50
HANFORD 0.00 1.77 91 1.71 88 1.94 10.10
BAKERSFIELD T 1.60 116 1.20 87 1.38 6.47
BISHOP 0.00 1.06 95 1.31 117 1.12 5.18
SALINAS 0.00 4.12 146 3.87 137 2.82 12.83
PASO ROBLES T 4.70 192 2.84 116 2.45 12.78
SANTA MARIA 0.00 2.68 95 1.95 69 2.81 13.95
Next report: Monday afternoon/December 16