December 2, 2020
Summary: The current barometric pressure at Pocatello, Idaho was 30.51 inches of mercury while LAX was reporting 30.02. that’s a good half inch of pressure difference between the northern Great Basin and the southern California coast. Winds over the Kern County mountains are slowly picking up. At last report, Sandburg was reporting northeast winds at 23 gusting to 31 MPH.
In the big picture, upper level high pressure has been nudged northward into the Pacific Northwest and the Canadian Rockies while a low center is over Oklahoma. That low has stretched westward into Arizona. This will create an easterly flow aloft over the southern half of California, meaning the winds at the upper levels of the atmosphere and at the surface are almost aligned. This pattern favors Santa Ana winds driving downslope off the Kern County mountains and into the Kern County portion of the valley floor. These winds are compressed as they move downslope, which heats the air. Therefore, I wouldn’t be surprised to see portions of Kern County surpass the 70 degree mark tomorrow along with plummeting dew points and humidity. The Sierra Nevada does an efficient job of blocking these winds from the remainder of the valley.
During the second half of the weekend, a low will drop out of the Pacific Northwest and into Nevada Sunday. Some models show this low moving across central California Monday, eventually settling off the northern Baja/southern California coast. For now, it appears this system will be precipitation free, but by Monday night and Tuesday yet another off shore flow will occur due to the position of the low.
I’m still looking at the pattern for roughly the 11th and 12th of December. I realize there’s a great deal of time between now and then, however models the past few days have been depicting high pressure jutting northeastward through the Pacific Northwest and into western Canada and the possible development of a strong winter storm over the Desert Southwest. This pattern would, in theory, drive a colder air mass into central California. We’re getting deep enough into December now for me to take these potential developments seriously.
Forecast: Other than occasional periods of high clouds, it will be mostly clear through Saturday night. Mostly clear to occasionally partly cloudy Sunday. Partly cloudy Sunday night and Monday. Mostly clear to occasionally partly cloudy Monday night through Wednesday.
Short Term:
| Madera 32/66/29/63 | Reedley 31/66/28/63 | Dinuba 29/65/27/62 | |
| Porterville 31/68/29/64 | Lindsay 29/66/28/63 | Delano 32/68/29/63 | |
| Bakersfield 46/71/38/62 | Taft 48/71/43/63 | Arvin 46/71/34/63 | |
| Lamont 44/71/33/63 | Pixley 30/68/28/63 | Tulare 28/65/27/62 | |
| Woodlake 30/65/27/62 | Hanford 32/67/29/63 | Orosi 29/65/27/62 | |
Winds: There is currently almost a half inch difference in pressure between southern Idaho and the southern California coast. That’s a significant difference. Wednesday night and Thursday, the winds aloft will be out of the east, almost aligned with surface winds. Historically, this pattern favors winds blowing downslope off the Tehachapi Mountains and the extreme southern Sierra Nevada, resulting in strong, gusty, east to southeast winds with gusts possibly as strong as 50 MPH at places like the bottom of the Grapevine and 35 MPH as far north as Bakersfield. the best chance of this occurring will be late tonight and Thursday morning. elsewhere, winds will be at or less than 10 MPH during the late morning and afternoon hours and variable in nature and at or less than 5 MPH with periods of near calm conditions during the night and early morning hours. Light winds will return to Kern County later Thursday night through Saturday.
Rain: Expect dry weather tonight and for at least the next 7 to possibly 10 days.
Frost: Tonight’s forecast will be considerably trickier than the past week or so. A strong off shore flow will begin tonight with the possibility of gusty east to southeast winds over the valley portion of Kern County. Most locations south of Delano will see winds in the 40 to 50 MPH range. We may begin to see some mixing in the atmosphere north of Kern County which would, in theory, nudge temperatures up a bit.
Coldest overnight lows tonight north of Kern County will drop down to 27 to 28 degrees with most flatland locations between 29 and 33 and above freezing conditions on hillsides.
This pending off shore flow will drive dew points down drastically in Kern County and should lower them somewhat over the remainder of the district, again giving the atmosphere the ability to radiate its heat skyward.
Lows as early as Friday morning may drop into the 24 to 26 degree range in those traditional cold locations and 27 to 29 elsewhere. There’s a greater risk of this Saturday morning and possibly Sunday morning.
There does seem to be a decent trend now in a low pressure system moving across the Pacific Northwest, tracking over Nevada Sunday and then over central California Sunday night and Monday. It remains to be seen, but if we keep our fingers crossed we may have a shot at reducing the radiational cooling process, especially Monday but also possibility Tuesday.
We should see yet another off shore flow Monday and Tuesday, due to the low positioning off the Baja coastline. I’m still watching the pattern for the 11th and 12th. Over the past few days, including today, models show a southwest to northeast oriented high from the Pacific northeastward into northern Canada and possibly a strong winter storm developing over the Desert Southwest. This could potentially pump some cold air into California. This far out, I’m definitely not ready to mention this as a freeze situation, but we’re deep enough into December where I take projections like this more seriously.
Lows Tonight:
| Terra Bella
31 |
Porterville
31 |
Ivanhoe
29 |
Woodlake
30 |
| Strathmore
30 |
McFarland
29 |
Ducor
31 |
Tea Pot Dome
30 |
| Lindsay
29 |
Exeter
29 |
Famoso
29 |
Madera
32 |
| Belridge
30 |
Delano
Af |
North Bakersfield
Af |
Orosi
29 |
| Orange Cove
30 |
Lindcove
29 |
Lindcove Hillside
Af |
Sanger River Bottom
27 |
| Root Creek
29 |
Venice Hill
30 |
Rosedale
Af |
Jasmine
Af |
| Arvin
Af |
Lamont
Af |
Plainview
31 |
Mettler
Af |
| Edison
AF |
Maricopa
Af |
Holland Creek
Af |
Tivy Valley
Af |
| Kite Road South
Af |
Kite Road North
Af |
AF=Above Freezing
Next report: December 3/am