December 16, 2019
Summary: Clear skies prevail over central California and the immediate waters off the California coast. Satellite imagery shows a low pressure system located about 800 miles off the northern California coast which is chugging steadily eastward. Temperatures this afternoon are actually a degree or two cooler than 24 hours ago but are just about where they should be for the time of year, ranging in the low to mid 50s. with upper level high pressure overhead, the freezing level is slowly nudging upward with the reading earlier today over Vandenberg at 8,100 feet. With generally clear skies for at least most of the night, radiational cooling will be strong. Many locations will be at or just below freezing tonight, with the exception of the larger urban areas. More below in the frost discussion.
Late Tuesday and Tuesday night, a low center will be just west of the Golden Gate. Models continue to indicate there will be significant differences between California and the Great Basin as opposed to off the northern California coast. This will create a squeeze play as winds always head towards the point of lowest pressure, blowing downslope off the Tehachapi Mountains and over the Kern County portion of the valley floor. If these winds make it all the way down to the valley floor, the time of greatest risk will be Tuesday afternoon and Tuesday night.
Models also show this low moving inland by early Wednesday and basically just falling apart with a minimal chance of showers from Merced northward.
Upper level high pressure will build in from the west later Wednesday and will dominate our pattern through Friday night. pockets of fog and low clouds will be prevalent during the early morning hours with daytime temperatures rising to marginally above average.
Over the weekend, a significant trough of low pressure will develop along the west coast. One models shows a secondary low forming along the northern California coast Sunday. It then is projected to slide down the coast, possibly moving across southern California Tuesday and Wednesday. this will be a tricky one to try to forecast this far out, but for now I have to say the chance of rain will begin to pick up Sunday but more especially Monday and Tuesday. One model also shows a secondary low racing out of the Gulf of Alaska and into California Christmas Day. In theory, this would renew the chance of showers.
The pattern for the day after Christmas and for several days thereafter appears cold as the low which will move through Christmas moves into the interior west. Some models are back to showing a north/northeast flow wrapping around the back side of the exiting system, possibly leading to some chilly nights. Stay tuned as longer range forecasts tend to change daily.
Forecast: Mostly clear skies tonight with high, thin clouds mixing in after midnight. Patchy fog later tonight and Tuesday morning. clouds will begin to increase Tuesday with mostly cloudy conditions Tuesday night into early Wednesday. clearing by midday Wednesday then mostly clear to occasionally partly cloudy Wednesday afternoon through Friday night with areas of night and morning fog and low clouds. Partly cloudy Saturday, increasing cloudiness Saturday night leading to a chance of rain Sunday with a continuing risk of rain Sunday night through Monday.
Short Term:
| Madera 30/56/37/57 | Reedley 31/56/36/57 | Dinuba 29/55/35/56 | |
| Porterville 30/57/36/58 | Lindsay 29/56/35/58 | Delano 31/57/37/58 | |
| Bakersfield 37/59/41/60 | Taft 41/59/41/59 | Arvin 32/59/38/60 | |
| Lamont 32/60/38/61 | Pixley 30/56/36/58 | Tulare 29/55/36/57 | |
| Woodlake 30/56/36/58 | Hanford 32/57/37/57 | Orosi 29/56/36/57 | |
Winds: Winds tonight will be generally at or less than 7 MPH with periods of near calm conditions. Winds north of Kern County Tuesday will be out of the east to southeast at 5 to 12 MPH. Over the valley portion of Kern County, it’s possible some strong gusty winds will set up during the day Tuesday, lasting through Tuesday night. one model suggests sustained winds of 18 MPH at Meadows Field early Tuesday evening. If these winds occur, strongest winds will be near the bottom of the Grapevine where winds could approach or possibly exceed 50 MPH. Elsewhere in Kern County, winds of 15 to 30 MPH are possible with stronger gusts. These winds will diminish late Tuesday night with winds of no more than 5 to 10 MPH Wednesday and light to calm winds Wednesday night through Thursday.
Rain: Expect dry conditions through at least Saturday if not Saturday night. a developing trough of low pressure will extend from the Gulf of Alaska to off the southern California coast by early next week. There is modeling indicating a secondary low will develop off the northern California coast then move inland through southern California Tuesday. If I were a betting man, I would bet the highest precipitation totals will be south of Kern County. Even so, a good chance of rain exists from Sunday and at times through Tuesday night. one model indicates a new low will race out of the Gulf of Alaska and into California Christmas Day for possibly another shot at picking up rain and mountain snow. After Christmas Day, models show high pressure taking over for at least a few days. Models this afternoon are all over the place in determining a particular pattern for the end of the decade.
Frost Discussion: Air temperatures as of 1:00pm were in the low to mid 50s. In other words, it’s a fairly typical December afternoon. Even though high, thin clouds will be streaming overhead, especially during the late part of the night, my feeling is they won’t hamper the radiational cooling process. Dew points this afternoon are fairly high, ranging in the upper 30s to the lower 40s. So, there won’t be critically cold temperatures tonight. coldest readings tonight in unprotected low spots will chill to 27 to 29 degrees for roughly 2 hours with most of your flat terrain locations ranging from 29 to 33 degrees and with hillsides in the mid 30s. the inversion tonight will be moderate with temperatures at 34 feet ranging from 3 to 6 degrees warmer.
Most locations will be above freezing Wednesday morning, however if cloud cover exits the premises earlier than anticipated, low to mid 30s would be the result.
Upper level high pressure will take over Thursday through Friday night with widespread low to mid 30s each night, even though daytime highs will be nudging upwards. From Sunday through Christmas Eve, overnight lows will remain above freezing due to anticipated heavy cloud cover and chances of precipitation. Conditions for Christmas Day and beyond may dip below freezing for a few nights. Currently, a critical pattern doesn’t look likely, but as a low moves into the interior west Christmas Day, the possibility of a north/northeast flow aloft and a potential strong off shore flow could lead to some subfreezing nights.
Lows Tonight:
| Terra Bella
30 |
Porterville
30 |
Ivanhoe
29 |
Woodlake
30 |
| Strathmore
30 |
Mcfarland
31 |
Ducor
31 |
Tea Pot Dome
30 |
| Lindsay
29 |
Exeter
29 |
Famoso
31 |
Madera
30 |
| Belridge
29 |
Delano
31 |
North Bakersfield
31 |
Orosi
29 |
| Orange Cove
30 |
Lindcove
30 |
Lindcove Hillside | Sanger River Bottom 27 |
| Root Creek
29 |
Venice Hill
30 |
Rosedale
32 |
Jasmine
31 |
| Arvin
AF |
Lamont
AF |
Plainview
30 |
Mettler
AF |
| Edison
AF |
Maricopa
32 |
Holland Creek
33 |
Tivy Valley
31 |
| Kite Road South
33 |
Kite Road North
30 |
AF=Above Freezing
Next report: Tuesday morning/December 17