January 20, 2018
Summary:As expected, plenty of upslope clouds have developed against the north facing slopes of the Kern County mountains and against the west facing slopes of the foothills of the Sierra Nevada. Points north of that have partly cloudy to clear skies at this hour. The upsloping is generating a few light showers near the base of the Tehachapi’s and snow showers above 3,000 feet. A strong north/northwest flow is evident and it continue to pump cold air in behind yesterday’s weather system.
The drier air now moving down the valley will begin to erode the cloud deck in Tulare and Kern Counties during the day. It is possible some upslope clouds could last into Sunday morning, however, I do believe most of this cloud cover will mix out, revealing mostly clear skies and leading to strong radiational cooling tonight. That cooling will allow conditions that would lead to fairly widespread frost. This is discussed below.
Dry weather will continue through Sunday night then the next weather system, which is quite weak, will move into northern California on Monday with light showers possible as far south as Fresno County. For now, it looks like the south valley will remain dry. A weak ridge of upper level high pressure will fill in behind the Monday event for dry weather Tuesday and Wednesday with some possible areas of morning fog.
From late Wednesday night through Thursday night, a considerably stronger winter storm will sweep in from the Gulf of Alaska. Some models are showing as much as a quarter to a half inch of rain north of Kern County with lesser amounts further south and possibly one to two inches of rain in the foothills. This system will slide eastward by Friday morning, allowing upper level high pressure to fill back in from the west. All of these models are predicting a strong ridge of upper level high pressure for next weekend and well into the following week.
Forecast: Mostly cloudy today into the evening in the south valley with a chance of a few light showers near the base of the Kern County mountains. Mostly clear to occasionally partly cloudy elsewhere. Gradual clearing tonight in the south valley with mostly clear skies elsewhere. Mostly clear Sunday after patchy morning fog and low clouds. Increasing cloudiness Sunday night leading to a chance of light showers as far south as Fresno County with the south valley remaining dry. Becoming mostly clear Tuesday through Wednesday with areas of morning fog and low clouds. Increasing cloudiness Wednesday night. rain late Wednesday night into Thursday night. mostly to partly cloudy Friday and Friday night. becoming mostly clear Saturday with areas of night and morning fog and low clouds.
Short Term:
| Madera 55/30/56/34/59 | Reedley 54/31/58/34/59 | Dinuba 56/29/58/33/58 | |
| Porterville 56/30/58/35/60 | Lindsay 55/29/58/33/60 | Delano 56/32/57/35/61 | |
| Bakersfield 54/36/59/34/61 | Arvin 53/32/56/36/61 | Taft 57/35/57/38/60 | |
| Lamont 55/31/57/35/60 | Pixley 56/29/58/34/59 | Tulare 55/28/58/33/58 | |
| Woodlake 56/30/57/35/59 | Hanford 56/30/58/33/59 | Orosi 55/28/58/34/59 | |
Seven Day Forecast:
| Tuesday
Patchy fog/partly cloudy 37/57 |
Wednesday
AM fog/PM sun 36/61 |
Thursday
Rain likely 42/55 |
Friday
Mostly cloudy 35/55 |
Saturday
AM fog/PM sun 36/58 |
Two Week Outlook: January 25 through January 31: This model now indicates a blocking ridge of upper level high pressure will be over and off the west coast. This pattern would drive the storm track well north. Temperatures would rise to marginally above average values, assuming the fog doesn’t take over, with very little chance of precipitation.
February: This model doesn’t really grasp at any particular pattern through the month. In fact, central California, if you believe this model, should have temperatures close to seasonal values with near average precipitation, as well.
February, March, April: This model goes all the way through April and it is calling for a ridge of upper level high pressure off the southern California coast to be the most dominant, but not the only, feature during the spring months. If this model has any credence at all, temperatures should be marginally above average with below average precipitation.
Winds: Winds will be generally less than 10 MPH with periods of near calm conditions through Tuesday.
Rain: Upsloping against the valley facing slopes of the Tehachapi’s has condensed the clouds enough for some snow showers and isolated showers in the extreme south valley. With upsloping continuing today, we’ll keep a slight chance of showers in the extreme south with dry conditions elsewhere. Dry weather will continue through Sunday night. on Monday, a weak weather system will move into northern California, possibly spreading light showers down to Fresno County. For now, I believe the south valley will remain dry. Tuesday and Wednesday will be dry until possibly late Wednesday night as a stronger winter storm moves in from the northwest. Some models are indicating as much as a quarter to a half inch could be added up north of Kern County with as much as a quarter inch in Kern County. So, expect rain Thursday into Thursday night with dry weather returning Friday and continuing through the weekend. In fact, dry weather will go on through at least the middle of the following week, if not longer.
Frost: Most locations were in the mid 30s to the lower 40s this morning due to wind conditions and upslope clouds. Forecast models show these clouds eroding later today and tonight with mostly clear skies after midnight. It’s possible some of these clouds could linger into Sunday morning, mainly in Kern County and southeast Tulare County, but that’s by no means guaranteed. For this report, I will operate under the assumptions that conditions will set up for a frost night.
With a cold air mass over the region, coldest locations could dip down to 26 to 28 degrees with most locations between 29 and 34. Durations will be fairly short.
The inversion will tighten up after midnight with temperatures at 34 feet ranging from 3 to 5 degrees warmer.
Sunday morning is a tough call. The timing of cloud cover ahead of the next weather system will play a large role. If the clouds arrive in time, mid 30s to lower 40s can be expected. If skies remain relatively clear, upper 20s to lower 30s will be possible in colder locations. Right now, I’m leaning towards the milder outcome, but that is low confidence at this juncture.
There should be plenty of cloud cover Tuesday morning and the air mass coming in behind this system is not particularly cold. Temperatures should range in the mid 30s to the lower 40s. a more significant Pacific storm will be headed in Thursday with rain, clouds, and above freezing conditions. The air mass behind this system will be relatively cold, but not as cold as the current air mass. With this in mind, mid to upper 30s look likely.
Upper level high pressure will take over for the weekend and beyond. No doubt we’ll get into another fog regime, maintaining above freezing conditions.
Lows Tonight:
| Terra Bella
29 |
Porterville
30 |
Ivanhoe
30 |
Woodlake
29 |
| Strathmore
28 |
McFarland
28 |
Ducor
30 |
Tea Pot Dome
30 |
| Lindsay
28 |
Exeter
28 |
Famoso
30 |
Madera
30 |
| Belridge
29 |
Delano
31 |
North Bakersfield
30 |
Orosi
28 |
| Orange Cove
29 |
Lindcove
28 |
Lindcove Hillside
34 |
Sanger River Bottom
26 |
| Root Creek
28 |
Venice Hill
29 |
Rosedale
30 |
Jasmine
30 |
| Arvin
32 |
Lamont
30 |
Plainview
29 |
Mettler
34 |
| Edison
33 |
Maricopa
30 |
Holland Creek
31 |
Tivy Valley
29 |
| Kite Road South
32 |
Kite Road North
29 |
AF=Above Freezing
Afternoon Dew Points Today: Mid 30s to the lower 40s. Mid 30s to the lower 40s.
Humidity, Visalia, 65%/95% Bakersfield, 70%.95%
Actual Humidity January 18, 2018: Delano, NA, Porterville, 97%/47%
Percentage of Sunshine Today/Tomorrow: Visalia: Today 50% tomorrow 80%, Bakersfield: Today 20% tomorrow 60%.
ET Rates Over the Past Seven Days January 18, 2018: Stratford .12, Parlier .14, Blackwell, .28 Lindcove .20, Arvin .23, Orange Cove .25, Porterville .14, Delano .NA., Madera Two 12. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 54, Parlier 53, Blackwell 56, Lindcove, 58, Arvin, 57, Orange Cove 51, Porterville 55, Delano NA, Madera Two 54
7.2
Record Temperatures: 74/23. Average Temperatures: 55/35
Heating Degree Days this Season: 1076, -425 Courtesy of the NWS
Average temperatures for January so far, 53.2 +8.7
Precipitation: Seasonal total/average/above or below average:
Since October 1, 2017 Fresno: 1.23 season. or -3.54. Month to Date: .82
Since October 1, 2017, Bakersfield: .88, or -1.76, Month to Date: .82
Water year season is from October 1st through September.
Chilling ours November 1st through February 28: Orange Cove, 545, Parlier, 583, Arvin, 541, Shafter, 641, Stratford, 484, Madera two, 955, Alpaugh, NA, Lindcove, 661, Porterville, 883. Hours at 45 or below 45.
Sunrise: 7:09 am Sunset: 5:12 pm. Hours of Daylight: 10:01
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 59 / 48 / 0.12 /
FAT : Fresno Airport 333 : DH1600 / 57 / 49 / 0.13 /
HJO : Hanford Airport 242 : DH1600 / 55 / 44 / 0.04 /
NLC : Lemoore Naval AS 234 : DH1600 / 56 / 43 / 0.06 /
BFL : Bakersfield Airport 496 : DH1600 / 53 / 47 / 0.15 /
VIS : Visalia Airport 292 : DH1600 / 54 / 45 / 0.10 /
ATEC1 : Avenal 787 : DH1323 / 54 / 46 / 0.04 /
PTV : Porterville Airport 442 : DH1600 / 52 / 46 / 0.11 /
TFTC1 : Taft 759 : DH1600 / 50 / 45 / 0.17 /
LOSC1 : Los Banos 120 : DH1600 / 58 / 49 / M /
Rainfall: Season % Last y. % Ave. Annual Ave.
STOCKTON T 3.66 57 11.13 174 6.39 14.06
MODESTO 0.02 3.38 60 9.06 160 5.65 13.11
MERCED 0.16 2.16 40 9.00 167 5.40 12.50
MADERA 0.12 1.43 26 7.78 141 5.52 12.02
FRESNO 0.13 1.36 28 8.90 184 4.84 11.50
HANFORD 0.04 1.72 37 5.38 114 4.70 10.10
BAKERSFIELD 0.15 1.03 39 4.90 184 2.67 6.47
BISHOP 0.00 0.20 8 4.15 175 2.37 5.18
SALINAS 0.02 2.22 41 7.99 146 5.48 12.83
PASO ROBLES 0.04 2.20 41 8.16 152 5.36 12.78
SANTA MARIA 0.02 1.97 35 8.88 156 5.71 13.95
Next Report: Saturday afternoon/January 20