February 12, 2019
Summary: I am looking at an amazing satellite in motion across the eastern Pacific Ocean and into California. Three separate weather systems will combine for quite a rain event over the next 60 hour or so beginning later tonight. A very strong subtropical low is moving northeastward between the California coast and Hawaii. An arctic low extends from British Columbia southwestward 2,000 to 3,000 miles out over the Pacific. In the meantime, we have a plethora of tropical moisture streaming towards the northeast under that tropical low northeast of Hawaii.
Already this afternoon, Doppler radar out of Monterey and Hanford is indicating a line of virga falling out of the advancing clouds. Virga is rain that doesn’t reach the ground. The lower levels of the atmosphere will rapidly moisten up with an increasing chance of showers later this evening, turning to rain after midnight and continuing through Thursday morning, heavy at times. Freezing levels have jumped from near 3,000 feet yesterday to 9,200 feet over Vandenberg as that warmer tropical air floods in from the southwest.
Models this afternoon are still indicating 6 to 10 inches of rain along the west facing slopes of the Sierra Nevada from the Kern County line northward with significant amounts of rain on the valley floor, possibly leading to local flooding. The rain will turn to showers Thursday afternoon as the arctic low begins to sink farther south. Showers will briefly end later Thursday night and Friday morning then a new, very cold low will drop southward from the Gulf of Alaska into the Pacific Northwest and northern California late Friday through Saturday night. expect periods of showers and snow once again well down into the foothills surrounding the valley.
New this afternoon on some models is yet another very cold modified arctic type system skirting the coastline of Canada and into northern and central California Monday for the possibility of more showers and very low snow levels. Finally, this system will move into the Great Basin Tuesday as the eastern Pacific high parks itself just off shore. The combination of a very cold trough of low pressure over the interior west and the high just off shore will theoretically create a north/northeast flow into California for the potential of more below freezing conditions beginning Tuesday morning.
The flow aloft Wednesday through Friday will be out of the northwest, maintaining below average temperatures. The low is expected to finally move inland Saturday for the possibility of temperatures actually rising to above average.
Forecast: A chance of showers later this evening. Rain, heavy at times, after midnight, continuing Wednesday through Thursday morning. Showers Thursday afternoon and evening then becoming mostly cloudy late Thursday night and Friday morning. Periods of showers at any given time from Friday afternoon through Monday evening. Partly cloudy Monday night and Tuesday.
Short Term:
| Madera 44/60/54/63 | Reedley 44/61/54/61 | Dinuba 43/59/53/60 | |
| Porterville 44/61/54/64 | Lindsay 43/60/53/63 | Delano 45/61/55/64 | |
| Bakersfield 48/62/56/65 | Taft 48/62/56/64 | Arvin 46/62/54/64 | |
| Lamont 46/61/55/65 | Pixley 45/61/55/63 | Tulare 44/60/54/62 | |
| Woodlake 44/61/54/63 | Hanford 45/60/54/63 | Orosi 43/60/53/62 | |
Winds: Winds will be out of the southeast tonight at 5 to 15 MPH, increasing to 15 to 25 MPH Wednesday through Thursday morning with gusts to 35 MPH possible. Gusts to 45 MPH are possible in Kern County, mainly near the base of the Tehachapi Mountains. Winds later Thursday afternoon through Friday will be out of the northwest at 10 to20 MPH with stronger gusts at times.
Rain: The chance for showers will arrive as early as later this evening then rain will become likely after midnight and become heavy at times by sunrise. Rain will continue at times Wednesday through Thursday morning, heavy at times mainly north of Kern County and especially along the eastern flank of the valley. The rain will turn to showers Thursday afternoon and evening before a brief slot opens up later Thursday night and Friday morning.
Rainfall amounts tonight through Thursday evening, north of Kern County and mainly along the east side of the valley, could range anywhere from .75 to 1.50. Along the west side, between .50 and 1.00 seems plausible. And even over the valley portion of Kern County, more than .50 would not be a shock.
The chance of showers will increase again Friday afternoon and continue on and off through the weekend with very low snow levels. For the first time, a few models this afternoon are showing another low forming, skirting the Canadian coast and moving into California Monday for the possibility of additional rain, ending Monday evening. Snow levels would be very low.
Dry weather will set up Tuesday and, if models are correct, will continue through the remainder of next week and possibly well into the following week, as well.
Frost Discussion: All locations will be above freezing tonight and each night through Monday morning. If there are several hours of clearing from Friday through Monday, lower 30s would not be out of the question. Some models are pointing to the development of a new semi-arctic low skirting the Canadian coastline over the weekend and spreading showers over the valley Monday with low snow levels. This system is expected to drive into the Great Basin Monday night and Tuesday. As that occurs, the eastern Pacific high will park just off shore, creating a north/northeast flow from western Canada into California. The possibility of overnight lows similar to this morning’s cannot be ruled out next Tuesday and Wednesday. This far out, obviously this is shaky, but considering the trends of this month I would not be surprised at all.
Next report: Wednesday morning/February 13