February 1, 2019
Summary: The first bands of mainly light showers are just now beginning to move inland from northern San Luis Obispo County northward into northern California. Even a few isolated embedded thunderstorms were showing up west of San Francisco but have since decreased in intensity. This is one of those complex, powerful Pacific storms that will have all kinds of ramifications for just about the entire state. Quantitative precipitation estimates for along the Sierra Nevada foothills indicate more than four inches of rain is possible in the foothill area of the Sierra Nevada with possibly as much as six feet of new snow from tonight through Saturday night above 7,500 feet. I tell people that sometimes, and they just shake their heads.
All of the isobars I mentioned the past couple of days are still off shore, but will move towards the coast during the night and inland after midnight through Saturday. Isobars are lines of equal pressure and when you see them tightly wound on a surface weather map, it means the potential for strong winds is there. One model has sustained winds at Bakersfield for midday Saturday at 34 MPH out of the northeast. The risk factor for high winds over the Kern County portion of the valley is high for later tonight, especially after midnight, and through the day Saturday. Strong winds can be expected along the west side with gusty winds elsewhere. All this is detailed in the wind portion of the report.
The center of the low will finally move on shore, but not until Saturday night so there will be a prolonged period of possibly strong winds and heavy rain. It’ll be Sunday morning before this monster finally moves east of the Sierra Nevada only to be replaced by another strong and much colder low pressure system. This storm’s origins are in western Canada and it will slide down the coast of the Pacific Northwest Saturday night and into Oregon and northern California Sunday. It will be in that position all the way into late Tuesday night. Even though this system will be carrying considerably less precipitation, it will keep bands of showers going along the isolated afternoon thunderstorms for this entire time frame. Snow levels will plummet to 2,500 feet near Yosemite to possibly 3,500 feet over the Kern County mountains. It’ll be Wednesday morning before the action finally ends with dry weather thereafter.
However, the high pressure off shore never really will move inland. Instead, we’ll end up with a cold trough over the interior west and a high off shore, initially creating a northeast flow then a northerly flow by Friday. This will result in well below average temperatures, both day time and nighttime.
Forecast: Periods of rain tonight through Saturday, locally heavy at times, especially along the east side of the valley north of Kern County. Expect strong, gusty, southeasterly winds to develop after midnight, continuing through Sunday. Showers Saturday night. periods of showers Sunday through Tuesday night. there will be a chance of isolated thunderstorms each afternoon through Tuesday. A chance of a few lingering showers into early Wednesday. Otherwise, Wednesday will be mostly to partly cloudy. Clearing Wednesday night. mostly clear Thursday through Friday.
Short Term:
| Madera 55/61/50/59 | Reedley 56/62/51/60 | Dinuba 55/60/50/60 | |
| Porterville 56/62/50/61 | Lindsay 55/61/50/59 | Delano 56/63/50/62 | |
| Bakersfield 59/66/52/64 | Taft 60/66/53/65 | Arvin 59/66/51/64 | |
| Lamont 58/66/52/64 | Pixley 57/62/50/60 | Tulare 55/61/50/59 | |
| Woodlake 55/61/49/59 | Hanford 56/62/50/59 | Orosi 55/62/49/60 | |
Winds: Winds through this evening will be mainly out of the southeast at 10 to 15 MPH with stronger gusts. After midnight, winds will increase out of the south to southeast, becoming 15 to 35 MPH by sunrise with stronger gusts. Winds Saturday through Sunday will be mainly out of the southeast at 15 to 35 MPH with gusts to 45 MPH possible north of Fresno and along the west side. In Kern County, there is high potential for very strong winds. One model gives Bakersfield sustained winds of 34 by midday Saturday with stronger gusts. Projected winds on top of the Tehachapi may exceed 70 MPH and it’s possible some of these winds may make it down the north facing slopes and onto the valley floor. Winds near Wheeler Ridge and near the bottom of th e Grapevine could gust to 60 to 70 MPH with 50 plus MPH gusts not out of the question. In a swath from the Arvin/Edison area all the way over the Belridge and Taft winds in the 20 to 35 MPH range with stronger gusts won’t be surprising. From Monday through Tuesday, expect periods of breezy weather at times.
Rain: Light rain is already spreading over the coast range with light showers showing up on radar over western Kings and Fresno Counties. The real precipitation, however, will not arrive until later this evening. There is high potential for heavy amounts of rain on the valley floor, especially along the east side north of Kern County. The dynamics of the storm are such that there will be strong rain shadows along the west side and in Kern County. However, the atmosphere has such a high degree of saturation due to the pineapple connection that these rain shadows may actually be over come with significant rain in the south and west portions of the valley, as well. Models continue to indicate possibly well over an inch of rain could fall on the east side north of Kern county and between a half and three quarters of an inch on the west side. One model actually gives Bakersfield almost .90 from tonight through Saturday night.
Much lighter showers will continue Sunday through Tuesday night as a much colder storm arrives and centers over northern California. Snow levels in the foothills will drop down near 2,500 feet year Yosemite and 3,500 feet over the Kern County mountains beginning Sunday, continuing through Tuesday night.
Dry weather will return Wednesday and continue the remainder of next week.
Frost Discussion: Above freezing conditions will continue through at least Tuesday morning. A very cold low will park over northern California Sunday through Tuesday night with periods of showers and lowering freezing levels. When the low finally exists at midweek, a northeast flow will develop aloft along with an off shore surface flow. This will drive a cold and drier air mass into the valley for the likelihood of low to mid 30s with the possibility of the coldest regions down to 27 to 29 or so, especially Thursday and Friday mornings. A cold northerly flow will continue right into the weekend for well below average temperatures which may keep low temperatures in the 30s next Saturday and Sunday, as well.
Next report: Saturday morning/February 2