February 17, 2019
Summary: The freezing level over Oakland earlier this morning was 3,700 feet while at Vandenberg it was 3,800 feet. Temperatures on the valley floor, as of 1:00pm were unusually cold, ranging from 44 at Visalia to 50 at Bakersfield. Dew points were still in the lower 40s which is a little higher than expected. Skies have already cleared along much of the west side and have partially cleared towards the center of the valley. As progressively drier air begins to feed in on a northwest surface flow and a northerly flow aloft, skies will gradually clear from north to south, although the lifting motion of the southern Sierra and the Kern County mountains may result in at least some cloud cover most of the night in portions of eastern Tulare County and areas of the valley portion of Kern County.
There is still a batch of light showers over Tuolumne and Merced Counties which will be moving southeastward, possibly lasting through the early evening as they journey down the valley. All the action should be over by nine or ten pm with the exception of the mountain areas where snow flurries may last into the morning hours over the Kern County mountains down to roughly 1,500 feet or so.
Skies will clear Monday as a dry, north/northeast flow aloft wraps around the back side of the exiting low which will finally be moving into the interior west. The aforementioned northerly flow will continue through Tuesday, leading to what promises to be a freeze event Tuesday and Wednesday mornings. This is discussed in the frost section.
There is one more of these very cold systems upstream at this point which will drop southward overland from western Canada, ending up in central California Wednesday night and Thursday. Since this storm is taking an overland trajectory on its journey southward, precipitation amounts are expected to be quite light and widely scattered. For this same reason, it will be very cold with snow levels possibly as low as 500 feet in the surrounding mountains and foothills. Both Porterville and Bakersfield have elevations of over 500 feet, so the possibilities are tantalizing.
Friday and possibly Saturday mornings could possibly also see local frost, but we’ll cross that bridge later in the week. At long last, though, a westerly flow will break through during the second half of this coming weekend for the beginning of a warming trend. As that’s occurring, a new low will be dropping southward into the Pacific Northwest, possibly affecting parts of northern California but for now we’ll go with a dry forecast for early next week. So far, it appears the precipitation line after early next week will remain to our north, so we’ll reflect that in our longer range forecasts.
Forecast: Still a chance for scattered showers and isolated thunderstorms through early this evening, ending by nine or ten oclock. Becoming mostly clear towards the center and west side of the valley and partly cloudy to cloudy elsewhere. Clearing Monday morning. Mostly clear Monday afternoon through Tuesday night and continued cold. Increasing cloudiness Wednesday with a small chance of light showers by later in the afternoon. Light showers likely Wednesday night into Thursday night with a slight chance of snow flurried Thursday night. partly cloudy Friday. Mostly clear to occasionally partly cloudy Friday night through Sunday.
Short Term:
| Madera 30/49/28/52 | Reedley 31/48/28/52 | Dinuba 30/48/28/53 | |
| Porterville 30/49/28/53 | Lindsay 30/49/27/53 | Delano 31/48/29/52 | |
| Bakersfield 34/48/31/54 | Taft 34/47/32/54 | Arvin 32/47/29/54 | |
| Lamont 33/47/30/53 | Pixley 31/48/28/53 | Tulare 30/48/27/52 | |
| Woodlake 30/49/28/53 | Hanford 31/49/29/53 | Orosi 29/49/27/53 | |
Winds: Winds this evening will be out of the northwest at 5 to 15 MPH, diminishing during the late evening hours and becoming generally less than 8 MPH with periods of near calm conditions after midnight. Winds Monday through Tuesday night will be generally at or less than 8 MPH with periods of near calm conditions, mainly during the night and morning hours. Winds Wednesday will be out of the southeast at 5 to 15 MPH.
Rain: As of the time of this writing, scattered showers were still occurring throughout the valley and will continue to do so, ending about 9:00 or 10:00pm with dry conditions later tonight through Tuesday night. precipitation will be generally less than .10 with possibly isolated locations at around .25 where isolated thunderstorms occur. Clouds will be increasing Wednesday ahead of our next chance of light showers which could begin early afternoon Wednesday, becoming likely Wednesday night through Thursday evening. The fact that this system will be taking an overland trajectory means amounts will probably be no more than .10 or .20 with more over the mountains. As you might expect, snow levels will be extremely low. Some models are still saying snow levels will be down to about 500 feet by Thursday evening. There are a number of locations in Tulare and Kern Counties and in extreme western Kings and Fresno Counties that are above 500 feet, so snow flurries on the valley floor cannot be ruled out Thursday evening. Dry weather will return Friday and, it appears, dry weather will continue through early next week, though some models show showers returning to northern California Sunday and Monday of next week. Models for later next week indicate the storm track will be farther north, so for now we’ll go with the flow.
Frost Discussion: As of 2:00pm, the dew points were generally in the upper 30s and lower 40s, which certainly is not extremely low by early spring standards. Still, we are dealing with a very cold air mass with freezing levels down to between 3,000 and 4,000 feet. There has been some clearing along the west side and towards the center of the valley and the clearing trend will continue through the night in those areas. The flow through the mid layer of the atmosphere is out of the northwest and out of the north up higher. This should result in enough clouds banking against the surrounding mountains for some cloud cover to remain over much of the night for much of Kern County and possibly southeastern Tulare County, though that’s by no means guaranteed. My feeling is, the first night of a freeze, such as this one, is chaotic with local wind conditions, mixing, and cloud cover. Still, where skies clear for several hours and winds are calm, readings from 28 to 31 cannot be ruled out. If your location happens to enjoy a canopy of cloud cover during the night, then expect low to mid 30s.
Tuesday and Wednesday mornings will be a tougher challenge as I do anticipate mostly clear skies and little or no wind. This will set the stage for strong radiational cooling. Lows in the 27 to 30 degree range are certainly possible each night with an isolated sandy river bottom out there possibly down to 25 to 26, but that would be only in very isolated spots.
Thursday morning will be above freezing due to heavy cloud cover and showers which may or may not hold for Friday morning. Ideal conditions Friday and possibly Saturday morning could see lows drop right back into the upper 20s to the lower 30s.
For now, it appears we will finally break out of this very cold pattern of the last three weeks with above freezing conditions Sunday morning and possibly beyond. I have to say, though, the two week model continues to indicate there will be below average temperatures right up through the first of March.
Lows Tonight:
| Terra Bella
30 |
Porterville
29 |
Ivanhoe
29 |
Woodlake
30 |
| Strathmore
29 |
McFarland
29 |
Ducor
30 |
Tea Pot Dome
29 |
| Lindsay
28 |
Exeter
28 |
Famoso
30 |
Madera
30 |
| Belridge
28 |
Delano
29 |
North Bakersfield
31 |
Orosi
29 |
| Orange Cove
29 |
Lindcove
28 |
Lindcove Hillside
32 |
Sanger River Bottom
27 |
| Root Creek
28 |
Venice Hill
29 |
Rosedale
32 |
Jasmine
31 |
| Arvin
32 |
Lamont
31 |
Plainview
30 |
Mettler
32 |
| Edison
31 |
Maricopa
30 |
Holland Creek
32 |
Tivy Valley
29 |
| Kite Road South
31 |
Kite Road North
28 |
AF=Above Freezing
Next report: Monday morning/February 18