December 27, 2019
Summary: Skies have cleared this afternoon over most of the valley. All of the regularly reporting stations were indicating mostly clear skies with the exception of Fresno which was reporting a broken layer of clouds based at 2,500 feet. Dew points are fairly uniform as of 1:00pm and are running in the upper 30s. With a relatively clear sky tonight, a combination of areas of frost and widespread dense fog will be the main challenges.
In the broad picture, yesterday’s storm system has shifted all the way into the Arizona/New Mexico border region. This is allowing upper level high pressure to build in from the eastern Pacific. A northerly flow aloft is currently underway, maintaining a moderately cold air mass over California.
The freezing level over Vandenberg earlier today had risen to 6,200 feet and 8,900 feet over Oakland, indicating a warm air inversion will set up tonight which should increase the chance of widespread dense fog Saturday morning.
In the far northeast Pacific is a developing low pressure system. Models continue to show it sliding southward just off shore Sunday through Monday. By Sunday night, the low will be just to the northwest of the Golden Gate then just off the southern California coast by Monday morning. as the storm slides southward just off the central coast, bands of light showers will pinwheel inland Sunday night and Monday morning. this will be a fast moving system with rapidly improving weather by late Monday afternoon. After Monday, a large upper high over the eastern Pacific will again shift inland, dominating our weather from New Year’s Day through January 4th. It appears the high will be suppressed southward about the 5th and 6th.
I took note of the two week model this afternoon which is suddenly calling for below average temperatures with an increasing chance of precipitation between the fourth and the tenth.
Forecast: Mostly clear tonight with widespread fog forming after midnight, fanning out through most of the valley by sunrise. Widespread fog and low clouds Saturday morning, becoming mostly clear during the afternoon. Fog reforming Saturday night and Sunday morning then increasing higher clouds Sunday afternoon. Showers likely Sunday night and Monday morning with a slight chance of showers Monday afternoon. Partly cloudy Monday night and Tuesday morning. mostly clear to occasionally partly cloudy Tuesday through Friday with widespread fog and low clouds during the night and morning hours.
Short Term:
| Madera 30/52/31/55 | Reedley 31/53/31/55 | Dinuba 30/52/31/54 | |
| Porterville 31/54/31/55 | Lindsay 30/53/30/55 | Delano 32/54/32/55 | |
| Bakersfield 35/55/35/57 | Taft 35/54/37/57 | Arvin 32/56/32/57 | |
| Lamont 32/55/32/57 | Pixley 30/55/31/56 | Tulare 30/52/31/54 | |
| Woodlake 31/53/31/55 | Hanford 32/54/32/55 | Orosi 30/53/31/55 | |
Winds: Winds will be generally at or less than 6 MPH with periods of near calm conditions through Sunday. Winds Sunday night and Monday morning will be out of the east or southeast at 8 to 15 MPH with stronger gusts possible, mainly in Kern County. Winds will be mainly out of the northwest Monday afternoon at 5 to 10 MPH, diminishing Monday evening.
Rain: Expect dry weather through Sunday. The chance for showers will begin to increase by Sunday evening, becoming likely Sunday night and Monday morning. the highest risk of rain will be in western Fresno, Kings, and Kern Counties which will be closer to the low as it passes southward to our west. Dry weather will return Monday afternoon and, if models are correct, may continue through much of the first week of January, although the new two week model which begins on January fourth is hinting at a possible cold and wetter pattern developing.
Frost Discussion: As of 1:00pm, dew points were generally in the upper 30s with most locations reporting mostly clear skies. With generally clear skies, fairly decent radiational cooling will begin tonight. this will be one of those nights where there will be a race between fog formation and frost. Coldest unprotected locations could drop down to 27 to 29 degrees for short durations. Most flatland type terrain or gentle slopes will range between 29 and 33. If fog and low clouds form more quickly than anticipated, then readings could be a tad warmer.
The inversion tonight will be weak to moderate with temperatures at 34 feet at most locations ranging from 3 to 5 degrees warmer.
For Sunday morning, much will hinder on the arrival of cloud cover ahead of the next Pacific storm from the Gulf of Alaska which will skirt the California coast. If clouds hold off until after sunrise, temperatures will be similar to tonight’s forecast. All locations will be above freezing Monday morning due to heavy cloud cover and a good chance of light showers. For Tuesday morning and several days thereafter, lows potentially ranging in the upper 20s to the mid 30s will prevail as the air mass behind the Sunday night/Monday storm event will be relatively cold, but nothing unusual for the season.
The two week model piqued my interest this afternoon as it’s now tilting towards below average temperatures and above average precipitation between the fourth and the tenth of January. For now, however, I see nothing to indicate a critically cold pattern is on the weather horizon.
Lows Tonight:
| Terra Bella
31 |
Porterville
31 |
Ivanhoe
30 |
Woodlake
31 |
| Strathmore
31 |
Mcfarland
30 |
Ducor
32 |
Tea Pot Dome
31 |
| Lindsay
30 |
Exeter
30 |
Famoso
32 |
Madera
30 |
| Belridge
30 |
Delano
32 |
North Bakersfield
32 |
Orosi
29 |
| Orange Cove
30 |
Lindcove
30 |
Lindcove Hillside
34 |
Sanger River Bottom
28 |
| Root Creek
29 |
Venice Hill
30 |
Rosedale
32 |
Jasmine
31 |
| Arvin
33 |
Lamont
33 |
Plainview
30 |
Mettler
33 |
| Edison
33 |
Maricopa
32 |
Holland Creek
33 |
Tivy Valley
30 |
| Kite Road South
33 |
Kite Road North
30 |
AF=Above Freezing
Next report: December 28/morning