January 15, 2021
Summary: Upper level high pressure is centered just off the central coast this afternoon. A strong warm air inversion resides over the valley floor. Take a drive up to Oakhurst this afternoon. The temperature at 1:00pm was 79 with a reading of 75 at Bass Lake. Most locations on the valley floor are ranging in the mid to upper 60s with Avenal reaching 70. Visibilities are generally 4 to 5 miles at most locations.
A fast moving weak wave of low pressure is currently moving through the Pacific Northwest and will race southeastward into the Great Basin Saturday. another fast moving wave of low pressure will race through central California Sunday night and into southern California Monday where it will form a closed low circulation. Out over the ocean, a southwest to northeast oriented ridge of high pressure will build into the Pacific Northwest, creating a northeast flow. Fortunately, the high will not build far enough to the north to pick up arctic air.
As the low races through, light snow showers are likely over the high Sierra and partly cloudy skies over the valley floor Monday. By early Tuesday, the low will set up shop just west of the northern Baja coastline. The counterclockwise circulation around the low, coupled with that northeast flow aloft and a strong surface high over the Great Basin will generate a strong Santa Ana wind event Monday through Tuesday with even a chance of a brief Mono wind event along the east to west facing canyons of the Sierra Nevada from Tulare County north. There is a chance the Santa Anas could leach down the slopes of the Tehachapi Mountains and into the extreme south valley.
The Baja low will be kicked eastward Wednesday night as a new a very cold low drops southward from western Canada into California Friday and Saturday. models show this feature to be fairly moisture starved, but it may form a low pressure system off the central coast, increasing the chance of light showers. That will be our best chance of rain next week.
If medium range models are correct, beginning a week from Monday we could possibly enter into a wet pattern. Keep in mind, though, that medium range models have frequently done us wrong this winter season.
Forecast: Mostly clear tonight with high and mid level clouds mixing in later in the night with areas of low clouds and fog developing towards the center of the valley after midnight north of Kern County. Mostly clear to occasionally partly cloudy Saturday through Sunday with well above average temperatures. Variable cloudiness Sunday night and Monday. Mostly clear to occasionally partly cloudy Monday night through Wednesday night. increasing cloudiness Thursday leading to a chance of light showers Friday.
Short Term:
| Madera 37/66/37/68 | Reedley 35/67/37/68 | Dinuba 35/65/36/67 | |
| Porterville 36/68/37/69 | Lindsay 34/67/35/68 | Delano 36/68/37/68 | |
| Bakersfield 43/70/44/70 | Taft 52/68/52/68 | Arvin 37/71/38/70 | |
| Lamont 38/70/39/71 | Pixley 36/68/37/68 | Tulare 34/66/35/67 | |
| Woodlake 35/66/37/68 | Hanford 37/66/38/68 | Orosi 34/65/35/67 | |
Winds: Winds through Sunday will be at or less than 10 MPH and variable in nature during the late mornings and afternoons and generally less than 5 MPH during the night and early morning hours with extended periods of near calm conditions. Later Sunday night through Monday evening, winds will be out of the north to northwest at 10 to 15 MPH. gusts over 30 MPH are possible along the west side. It’s also possible that strong Santa Ana winds affecting southern California could move far enough downslope for locally gusty east to southeast winds in the extreme south valley late Sunday night through Monday night.
Rain: It appears our next chance for measurable rain will not occur until late Thursday night through Saturday of next week. Some models show a very cold low from western Canada dropping into California, possibly forming a new low circulation off the central coast. Models do show a lack of moisture with this system, however if that low does form to our west, it might pick up enough moisture from the ocean to spread light showers down the valley. Medium range models show a wet and active pattern beginning a week from Monday, but keep in mind, medium range models have been burning us all winter.
Frost: All locations will be above 32 degrees tonight through Monday morning. there is a fundamental change in some models this afternoon. Basically, the pattern shift of a low forming over southern California Monday then off the northern Baja coast Tuesday remains. However, the southwest to northeast oriented ridge of high pressure is shown building into the Pacific Northwest, though not far enough to transfer a colder air mass into central California. The latest model information points towards readings remaining in the low to mid 60s during the day. The element we’ll need to watch closely is a very strong off shore flow Sunday night through Tuesday which may exchange out the current air mass for a drier one with lower dew points. For now, it appears the coldest it could possibly get would be upper 20s to lower 30s, but with other factors such as strong wind energy creating mixing, plus the possibility of clouds from the system to our south, means above freezing conditions may be maintained. By Thursday night and Friday morning, models are showing increasing cloud cover for a chance of showers. This will be a very cold weather system, but one which will give us enough cloud cover to maintain above freezing conditions.
Lows Tonight:
All locations will be above 32 tonight.
Next update: January 16/am