January 26, 2021
Summary: Rain is rapidly spreading over northern California. At this hour, light precipitation had spread as far south as Monterey. The parent low continues to intensify off the Oregon coast and will be centered roughly 200 miles west of Crescent City by early Wednesday morning. models continue to indicate very strong differences in surface pressure will exist between the northwest coast of California and the inland sections of southern California. Strong winds will begin to pick up from Fresno County north during the later evening hours, spreading southward during the predawn hours.
The exact configuration that will unfold over the next 72 hours is coming more into focus. Initially, a 170 MPH jet stream will flank underneath the low and into northern California later tonight and Wednesday morning with strong winds and heavy precipitation. From late Wednesday afternoon thoroughly roughly midday Thursday, some models are pinpointing a pineapple connection roughly 250 miles wide sweeping from north of Hawaii and coming on shore from the Bay Area on the north to roughly Santa Maria on the south, perpendicular to the Coast Range and the Sierra Nevada. In other words. It appears we are right smack in the bulls-eye, especially from late Wednesday afternoon through midday Thursday.
Potential rainfall amounts and wind velocity are discussed below.
The AR will drop southward into southern California late Thursday night and Friday as the heavy rain turns to periods of showers Friday. A weak ridge of upper level high pressure off the California coast will result in dry weather Saturday through Monday. Another cold low will drop out of the Gulf of Alaska, possibly forming a similar configuration, Tuesday and Wednesday of next week. However, on paper this system doesn’t appear to be nearly as strong.
Forecast: Rain reaching into Fresno County by midnight, spreading slowly southward during the early morning hours. Rain, heavy at times, Wednesday through Thursday north of Kern County with periods of showers in Kern County. Rain tapering off late Thursday night with periods of showers Friday, decreasing during the afternoon. Partly cloudy Friday night through Monday with patchy morning fog. Increasing cloudiness Monday night leading to a chance of rain Tuesday.
Short Term:
| Madera 44/57/50/58 | Reedley 43/58/51/58 | Dinuba 43/57/50/56 | |
| Porterville 43/58/50/59 | Lindsay 42/58/50/57 | Delano 43/59/51/58 | |
| Bakersfield 44/59/53/59 | Taft 45/58/53/59 | Arvin 43/60/52/58 | |
| Lamont 44/59/52/58 | Pixley 42/58/51/59 | Tulare 42/56/50/57 | |
| Woodlake 42/58/51/57 | Hanford 42/58/51/57 | Orosi 41/57/49/57 | |
Winds: Winds this evening will be mainly out of the southeast at 8 to 15 MPH. later tonight north of Kern County and along the east side, winds will be mainly out of the southeast at 15 to 25 MPH with gusts to 35 MPH, continuing Wednesday and Wednesday night. Towards the center but more especially along the west side of the valley, winds after midnight through Wednesday evening will be out of the southeast but at 20 to 35 MPH with gusts to near 50 MPH possible, especially near the base of the Coast Range. In Kern County, the main concern is the extreme south valley near the base of the mountains. Winds will increase out of the south to southeast at locations such as the bottom of the Grapevine to 25 to 45 MPH. Local gusts to 70 MPH cannot be ruled out. Elsewhere, at places such as Taft, Mettler, Wheeler Ridge, Arvin/Edison, and Lamont, gusts in excess of 55 MPH are possible. Gusts to 45 MPH are possible as far north as Oildale.
Later Wednesday night and Thursday, throughout the valley, winds will continue at 10 to 20 MPH from the southeast with stronger gusts. Winds Thursday night and Friday will be generally less than 20 MPH with stronger gusts, mainly in the vicinity of showers.
Rain: If some of the short term models are correct, our infamous pineapple connection will come on shore from near the Bay Area on the north to Santa Maria on the south. In other words, we’re smack in the bulls-eye, especially Wednesday afternoon through midday Thursday. Even though rain shadows will develop along the west side and in Kern County, the fact that so much moist air will be moving overhead courtesy of a 170 MPH jet stream means that even many west side locations will pick up significant amounts of rain. For now, I don’t believe the heaviest precipitation will arrive in Kern County until later Thursday through Friday.
Rainfall amounts north of Kern County and over the eastern half of the valley will generally range from 1.50 to 3,00 inches. Along the west side of the valley, also north of Kern County, anywhere from .75 to 2.25 is likely. Rainfall may be particularly heavy along the lip of the Coast Range. In Kern County, anywhere from .50 to 1.00 seems plausible. Dry weather will prevail over the weekend and through Monday.
Some medium range models project a low will drop out of the north into a position similar to our current system, but weaker, for a chance of rain Tuesday and Wednesday of next week.
Frost: All locations will be above 32 degrees tonight and each night for at least the next week. Models after Wednesday of next week are trying to show a colder, drier pattern. The configuration would set up a north to northeast flow over California, possibly pumping some modified air into the region.
Next update: January 27/am