January 21, 2019
Summary: Towards the center and west side of the valley, skies are clear to partly cloudy as of 1:30pm. Towards the eastern and southern flanks of the valley, there’s still a lot of cloud cover against the Sierra Nevada foothills in Tulare County and are banking up against the north facing slopes of the Kern County mountains. These clouds, at least in part, will probably remain through the night and into the morning Tuesday. The brand new air mass now in place is definitely colder than the previous one. The latest freezing level taken over Vandenberg was only 4,800 feet and 4,200 feet over Oakland. As of 1:00pm, Tehachapi was reporting a temperature of just 36 and up at 8,200 feet, Bear Mountain was reporting 28 degrees.
The main forecast challenges the next couple of mornings will be two fold. The first will be increasing amounts of night and morning fog and low clouds, especially beginning Wednesday morning. The other will be areas of below freezing temperatures. It’s been a while since we’ve had to deal with subfreezing readings. Even so, nothing serious is expected.
A very weak trough will move through the Pacific Northwest Tuesday and Tuesday night then a giant high will anchor itself over the eastern Pacific while expanding northward and eastward. This will serve as a blockade against any Pacific storms. As warm subsiding air begins to develop under a dome of high pressure, a strong low level warm air inversion will develop, sealing the valley’s fate. As temperature/dew point spreads begin to narrow each night, fog and/or low clouds will become more prevalent. Possibly as early as Thursday, we could see some locations with little or no sunshine at all, especially near the center of the valley. This will be a recurring theme through the weekend and well into next week.
Models had pointed to some kind of a change about the first, and that still appears possible, but different than what had been indicated. For now, my main challenge will be the fog and its affect on both overnight lows and daytime highs.
Forecast: Mostly clear to occasionally partly cloudy towards the center and west side of the valley and from Fresno northward on the east side. Partly to mostly cloudy in much of Tulare and Kern Counties through Tuesday morning. Clearing Tuesday afternoon. Mostly clear Tuesday night with areas of fog developing, possibly becoming widespread by morning. Widespread fog and/or low clouds nights and mornings each day through Monday with afternoon clearing in some areas.
Short Term:
| Madera 32/53/30/52 | Reedley 33/53/30/53 | Dinuba 32/52/30/53 | |
| Porterville 34/53/30/51 | Lindsay 31/53/29/54 | Delano 35/53/33/54 | |
| Bakersfield 39/56/34/58 | Taft 41/56/37/58 | Arvin 37/56/33/58 | |
| Lamont 38/55/33/58 | Pixley 34/53/31/54 | Tulare 32/52/30/54 | |
| Woodlake 33/55/31/55 | Hanford 35/54/31/56 | Orosi 32/53/30/56 | |
Winds: Winds this evening will be out of the northwest at 5 to 12 MPH, diminishing during the later evening hours. After midnight and through Thursday, winds will be generally less than 7 MPH with extended periods of near calm conditions.
Rain: Expect dry weather for the next seven to possibly ten days.
Frost Discussion: Dew points this afternoon have tanked and are generally in the upper 30s to the lower 40s as compared to low to mid 50s the past few days. Air temperatures are generally in the low to mid 50s. cloud cover varies widely, varying to clear to partly cloudy along the west side and in the center of the valley to mostly cloudy to overcast in Tulare and Kern Counties. That is pretty much as expected. I would not be surprised to see portions of southeastern Tulare County and Kern County remain under some degree of cloud cover for much, if not all, of the night with generally clear skies towards the center and west side of the valley as well as from Fresno County north on the east side. This is the first night behind a storm system and typically there are many variations due to cloud cover, wind conditions, mixing, etc. and I anticipate that tonight will be no exception.
Dew points are certainly low enough for widespread low to mid 30s, especially north of Kern County, with a small chance of coldest locations being to 29 to 30 or so.
The inversion tonight will be quite weak with temperatures at 34 feet only 2 to 4 degrees warmer, at best.
We will see more locations at or below freezing Wednesday and Thursday mornings as the atmosphere settles down and a warm air inversion associated with building high pressure aloft takes over.
Coldest unprotected wind sheltered river bottom and like locations could drop down to 27 to 29 for short duration with many other locations between 30 and 34.
Fog will be more and more of a player as we progress through the week, plus we will begin to see slow moderation, resulting in temperatures generally above freezing beginning Friday. Beyond Friday, nothing suggests another particularly cold air mass affecting the region this weekend or next week, for that matter.
Lows Tonight:
| Terra Bella
Af |
Porterville
Af |
Ivanhoe
31 |
Woodlake
32 |
| Strathmore
Af |
McFarland
31 |
Ducor
Af |
Tea Pot Dome
Af |
| Lindsay
31 |
Exeter
30 |
Famoso
Af |
Madera
32 |
| Belridge
32 |
Delano
Af |
North Bakersfield
Af |
Orosi
32 |
| Orange Cove
32 |
Lindcove
30 |
Lindcove Hillside | Sanger River Bottom
29 |
| Root Creek
30 |
Venice Hill
32 |
Rosedale
Af |
Jasmine
Af |
| Arvin
Af |
Lamont
Af |
Plainview
32 |
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: Tuesday morning/January 22