January 24, 2018
Summary: Rain has spread over most of northern California. Precipitation is approaching Sacramento and San Francisco, but the portion of the front off the central coast appears to be losing its upper air support, as expected. Showers will spread down the valley by late evening and during the early morning hours. By the time this system moves into Kern County, it will be a shadow of its former self. The far southern portion of the valley and the Tehachapi Mountains will be the last regions to receive potential light showers. Showers will continue for a time Thursday morning but by midday the front will be east of the Sierra Nevada, bringing the precipitation to a halt.
Upslope clouds will develop along the Sierra Nevada foothills and the Tehachapi Mountains, leaving mostly to partly cloudy skies in portions of the east valley and/or Kern County possibly through Friday morning. The air mass settling in behind the front is relatively cold, but certainly nothing unusual for late January. It is possible there could be areas of frost Friday through Sunday, however during the late part of the weekend and into early next week, upper level high pressure will again cap the valley floor with a warm air inversion. This will become more and more conducive to widespread fog and low clouds.
The upper high along the coast will remain for all of next week and medium range models favor a dry pattern for the first week in February.
Forecast: Increasing cloudiness this afternoon. Showers spreading down the valley tonight then a chance of showers Thursday morning. Partly to mostly cloudy Thursday afternoon through Friday morning. Mostly clear to occasionally partly cloudy Friday night through Saturday with increasing amounts of fog and low clouds. Mostly clear Sunday through Wednesday, but with extensive fog and low clouds nights and mornings, possibly lasting through the day in some areas.
Short Term:
| Madera 45/57/33/58 | Reedley 43/58/32/58 | Dinuba 44/59/32/59 | |
| Porterville 45/59/32/59 | Lindsay 44/58/32/58 | Delano 45/60/33/59 | |
| Bakersfield 46/60/36/58 | Arvin 45/60/34/59 | Taft 47/59/38/60 | |
| Lamont 44/60/33/59 | Pixley 43/59/32/59 | Tulare 43/57/31/58 | |
| Woodlake 45/58/32/59 | Hanford 45/59/32/59 | Orosi 44/60/33/59 | |
Winds: Winds will be mainly out of the southeast through the evening hours at 5 to 15 MPH. winds later tonight and Thursday will be out of the northwest at 10 to 15 MPH, diminishing Thursday night. winds Friday and Saturday will be generally less than 10 MPH with periods of near calm conditions.
Rain: Precipitation is rapidly moving into the Bay Area and Sacramento. Analyzing the cold front off the central coast, we find the southern flank of the front, or the portion that will move through the valley tonight, is losing its upper air support. Even so, light rain will spread down the valley tonight into early Thursday with showers rapidly tapering off Thursday morning. Dry weather will set up Thursday afternoon. It’s possible some up slope light showers could occur along the Sierra Nevada and the extreme south valley, otherwise dry weather will continue Thursday night through the weekend and more than likely through all of next week.
Rainfall amounts will not be impressive with this system. Most locations north of Kern County will pick up between a tenth to a quarter of an inch and likely just a few hundredths north of Kern County.
Frost Information: All locations will be above 32 degrees tonight. Clouds are already increasing ahead of a rapidly moving cold front which will spread light showers down the valley tonight and early Thursday. On Friday morning, we should see our old friends the upslope clouds in their usual locations. The air mass moving in behind the front is relatively cold but nothing to write home about for late January. It’s possible a few locations could dip down into the lower 30s Friday morning where skies clear and winds die off. There is a greater risk of low 30s Saturday and Sunday mornings with even a small chance of a few low pockets briefly getting into the upper 20s. by Sunday, more and more fog will be fanning out throughout the valley and by early next week it may take over as a warm air inversion again clamps down on the valley. Therefore, most of next week should see above freezing readings. But if for some reason the fog isn’t quite as extensive as I currently believe, low to mid 30s would be possible. There remains no evidence of a pattern which could move cold air into the west, so a serious frost or freeze is just not in the forecast for the short or medium term.
Lows Tonight: All locations will be above freezing.
Next report: Thursday morning, January 25