January 21, 2019
Summary:The low pressure system and its associated cold front has moved into the Great Basin this morning. There are still some showers occurring over the Sierra Nevada and the Kern County mountains. Oddly enough, at last report Tehachapi was reporting light rain with a temperature of 32 degrees. Sandberg above the ridge route was reporting light snow at 33 degrees. Go figure.
As the storm over the Great Basin speeds eastward, skies will begin to clear towards the center and west side of the valley. A north/northwest flow will prevail aloft through Tuesday morning, meaning upslope clouds will bank up against the valley facing slopes of the Tehachapis and the west facing slopes of the Sierra Nevada. Widespread clear will take place towards the center and west side of the valley.
The air mass diving southward along the backside of the low is colder with snow levels down to 3,500 to 4,000 feet. Now that we’ve exchanged air masses, at least local frost is a distinct possibility beginning tonight but especially on Wednesday and Thursday mornings as the air mass stabilizes. At midweek, a rapidly expanding upper level high will develop over the eastern Pacific and by Friday will ridge as far north as Alaska. California will be on the eastern side of this high. Temperatures will be above average above the valley floor however, as a strong warm air inversion develops underneath that high, the ground rules will be set for increasing amounts of night and morning fog and low clouds possibly lasting all day in some areas. This pattern is projected to be with us for quite a while, meaning we will have stable conditions through the end of the week and more than likely next week, as well.
Some of the medium range models are suggesting a possible change about the first of February, but after today fog will begin to determine our weather fate.
Forecast: Remaining mostly cloudy along the eastern and southern flanks of the valley today through Tuesday morning. Becoming mostly clear towards the center and west side of the valley. Clearing everywhere Tuesday afternoon. From Tuesday night through Monday of next week, expect increasing amounts of fog and low clouds, possibly locally persistent through the day by Thursday and each day thereafter.
Short Term:
| Madera 56/34/54/31/57 | Reedley 55/34/53/32/56 | Dinuba 54/33/52/30/55 | |
| Porterville 56/34/53/30/57 | Lindsay 56/32/53/30/57 | Delano 56/35/53/33/56 | |
| Bakersfield 54/49/57/45/59 | Taft 57/41/57/37/60 | Arvin 53/39/57/33/60 | |
| Lamont 55/37/56/33/59 | Pixley 55/34/53/31/56 | Tulare 54/34/53/30/56 | |
| Woodlake 54/34/53/31/57 | Hanford 55/35/54/32/57 | Orosi 55/32/53/30/56 | |
Seven Day Forecast:
| Thursday
AM fog/PM sun 33/54 |
Friday
AM fog/PM sun 39/55 |
Saturday
AM fog/PM sun 42/57 |
Sunday
AM fog/PM sun 42/58 |
Monday
AM fog/PM sun 43/55 |
Two Week Outlook: January 28 through February 3: This model indicates there’s a possible change somewhere around February 1 which, in theory, could bring precipitation back to central California. This same model also indicates a generally west to southwest flow, meaning temperatures will be 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: Later today along the west side, winds will be out of the northwest at 10 to 20 MPH with stronger gusts. Elsewhere, winds will be mainly out of the northwest at 5 to 12 MPH with stronger gusts, mainly from Fresno County north. Winds will diminish this evening with winds of generally less than 7 MPH and extended periods of near calm conditions through Thursday.
Rain: There is still a slight chance of a few light showers for a time this morning, mainly near the
Sierra Nevada foothills. Dry weather will prevail this afternoon and for the next week to possibly ten days.
Frost Discussion: The storm that brought precipitation and gusty winds last night is now east of the Sierra Nevada. A north/northwest flow is wrapping around the back side of the low and into California, causing cooler air to surge into the valley. Even though this is almost a northerly flow, its origins are over the Pacific Northwest and not polar regions. Still, it’s cooler air with widespread low to mid 30s over the next couple of nights. I anticipate upslope clouds will develop today along the north facing slopes of the Kern County mountains and the west facing slopes of the Sierra Nevada. These clouds may hang in there all the way into Tuesday morning, but generally clear skies will prevail towards the center and west side of the valley.
Coldest overnight lows tonight will range from 28 to 30 but only in locations with clear skies and calm winds and are generally low lying locales. This is the first night after a storm passage and generally matters are pretty chaotic in the atmosphere in those situations. Where cloud cover prevails, readings will probably only drop into the mid 30s to the lower 40s.
There’s a greater risk for Wednesday and Thursday mornings for lower 30s and isolated upper 20s as the relatively cold air settles onto the valley floor and high pressure caps the valley with a warm air inversion.
This is by no means a threatening situation. Add to that the fact that once the inversion sets up, fog and low clouds will become more and more widespread, possibly hanging in there all day in some locations, which would certainly modify lows.
Medium range models continue to show this high in place through the end of the month with arctic type masses remaining well to our east.
Lows Tonight:
| Terra Bella
af |
Porterville
Af |
Ivanhoe
31 |
Woodlake
Af |
| Strathmore
Af |
McFarland
32 |
Ducor
Af |
Tea Pot Dome
Af |
| Lindsay
31 |
Exeter
30 |
Famoso
Af |
Madera
32 |
| Belridge
32 |
Delano
Af |
North Bakersfield
Af |
Orosi
32 |
| Orange Cove
32 |
Lindcove
31 |
Lindcove Hillside | Sanger River Bottom
29 |
| Root Creek
30 |
Venice Hill
Af |
Rosedale
Af |
Jasmine
Af |
| Arvin
Af |
Lamont
Af |
Plainview
Af |
Mettler
Af |
| Edison
Af |
Maricopa
Af |
Holland Creek
af |
Tivy Valley
Af |
| Kite Road South
Af |
Kite Road North
Af |
AF=Above Freezing
Afternoon Dew Points Today: Low to mid 40s. Kern, Low to mid 40s.
Humidity: Porterville: 70%/100%, Bakersfield: 60%/90%
Actual Humidity January 20, 2019: Delano, NA, Porterville, 98%/64%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 50%, tomorrow 60% Bakersfield: Today: 20% Tomorrow: 50%
ET Rates Over the Past Seven Days: Stratford .24, Parlier .27, Blackwell .32, Lindcove .25, Arvin .53, Orange Cove .28, Porterville .25, Delano NA Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 54, Parlier 53, Blackwell 54, Lindcove, 57, Arvin, 54, Orange Cove 57, Porterville 53, Delano NA
Record Temperatures: 72/19. Average Temperatures: 55/36
Heating Degree Days this Season: 1116 -424
Courtesy of the NWS
Average temperature for January so far: 50.1 +5.5
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 4.42 season. or -.48, Month to Date: 2.09 +.66
Since Oct 1, 2018, Bakersfield: 2.27, or -.43. Month to Date: .97 +.23
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove, 508, Parlier, 521 , Arvin, 461 Shafter, 531 Stratford, 515, Delano 523, Lindcove, 786, Porterville, 1070
Hours at 45 or below 45.
Sunrise: 7:08 am Sunset: 5:13 pm. Hours of Daylight: 10:03
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 67 / 48 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 63 / 48 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 62 / 44 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 62 / 42 / 0.00 /
BFL : Bakersfield Airport 496 : DHM / 64 / 46 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 62 / 45 / M /
ATEC1 : Avenal 787 : DH1556 / 67 / 45 / 0.00 /
PTV : Porterville Airport 442 : DH1600 / 62 / 45 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr Season % L.Y. % Ave. Ave. yearly total
STOCKTON 0.22 7.91 122 3.66 57 6.47 14.06
MODESTO T 6.32 110 3.38 59 5.74 13.11
MERCED 0.00 6.00 109 2.16 39 5.48 12.50
MADERA 0.00 4.47 80 1.43 26 5.59 12.02
FRESNO 0.00 4.00 82 1.36 28 4.90 11.50
HANFORD 0.00 3.32 70 1.72 36 4.75 10.10
BAKERSFIELD 0.00 2.27 84 1.03 38 2.70 6.47
BISHOP 0.00 3.23 135 0.20 8 2.40 5.18
SALINAS T 5.59 100 2.22 40 5.57 12.83
PASO ROBLES 0.00 6.35 117 2.20 40 5.44 12.78
SANTA MARIA 0.00 6.38 110 1.97 34 5.80 13.9
Next report: Monday afternoon/January 21