January 18, 2018
Summary: The low clouds from the first part of the day are rapidly dissipating as a weak southeast flow moves up the valley. Higher clouds are increasing over the northern half of the valley ahead of a cold front which is spreading light showers over northern California down to a Sacramento/San Francisco line. The front will move steadily southward tonight, spreading light showers over the area. I do anticipate something of a rain shadow along the west side and, of course, in Kern County. But the opposite is true over the Sierra Nevada where lift from a strong southwesterly flow aloft will provide at least a healthier dose of precipitation. Eight to ten inches of snow are possible in the Sierra north of Tulare County with lesser amounts further south.
Scattered showers are possible through Friday night as a cold pool of relatively unstable air moves overhead. Saturday through Sunday night will be dry as a weak ridge moves in from the west. However, with a fairly strong push of northwesterly winds aloft, upslope clouds will form along the Sierra Nevada and the valley facing slopes of the Kern County mountains so clearing, especially along the eastern and southern portions of the valley, will be slow.
Local frost is possible Sunday morning as the colder air stabilizes on the valley floor. More in the frost discussion.
The next weather system looks at least a little more promising for light showers Monday and Monday night. the best dynamics with this system will be over northern California, however light showers are possible from mainly Fresno County north.
Models continue to show a third system moving in late Wednesday night and Thursday. On paper, this is the most promising of the three… at least for now.
Forecast: Increasing cloudiness this evening with light showers spreading down the valley. Scattered showers Friday and possibly Friday night. mostly to partly cloudy Saturday. Mostly clear to partly cloudy Saturday night through Sunday. Increasing cloudiness Sunday night with a chance of light showers Monday through Monday night, mainly from Fresno County northward. Mostly to partly cloudy Tuesday. Becoming mostly clear to partly cloudy Tuesday night and Wednesday morning with morning fog. Increasing cloudiness Wednesday night with a chance of rain Thursday.
Short Term:
| Madera 50/56/34/56 | Reedley 49/57/33/56 | Dinuba 48/56/33/56 | |
| Porterville 49/57/34/57 | Lindsay 49/58/33/57 | Delano 51/58/37/57 | |
| Bakersfield 50/58/38/57 | Arvin 48/57/37/57 | Taft 51/59/39/57 | |
| Lamont 49/58/36/57 | Pixley 49/57/35/56 | Tulare 47/56/34/57 | |
| Woodlake 48/57/35/57 | Hanford 50/57/35/57 | Orosi 49/57/34/56 | |
Winds: Winds will be mainly out of the southeast at 5 to 15 MPH before midnight. During the early morning hours, winds will be mainly out of the northwest at 10 to 20 MPH with locally stronger gusts. Winds Friday night will be mainly out of the northwest at 5 to 15 MPH and 5 to 10 MPH Saturday. Winds Saturday night and Sunday will be generally at or less than 10 MPH.
Rain: As of the time of this writing, light showers had spread as far south as a Sacramento/San Francisco line. A cold front will move steadily down the valley tonight and early Friday with light showers, especially just ahead of and behind the front. There is a strong southwesterly flow along the frontal system which will no doubt create rain shadows in the usual locations and rainfall totals in those locations may be fairly light. The east side north of Kern County should do better, but even there I’m only expecting about a tenth or two north of Kern County and less than a tenth of an inch in Kern County. The chance of light scattered showers will continue through Friday night with dry weather returning Saturday through Sunday night. the next system upstream will spread showers over the northern half of the state. In the valley, that translates to Fresno County northward, but we’ll add a chance of light showers in the south valley. Expect dry weather Tuesday through Wednesday. The third system will approach late Wednesday night for the possibility of rain for the entire valley Thursday. After Thursday, for now models are pointing to dry conditions.
Frost Information: A cold front will move down the valley tonight with only light showers and with a chance of scattered light showers Friday through Friday night. the air mass coming in behind the front is substantially colder and where it clears Saturday morning, temperatures will fall well down into the 30s with a slight chance of coldest locations in the lower 30s. There is a greater risk of local areas of frost Sunday morning with some possible upper 20s in the coldest wind sheltered areas where it remains clear. Clouds should be increasing Monday morning, maintaining above freezing conditions. Tuesday and Wednesday’s temperatures will depend on cloud cover. For now, it appears most locations will drop into the 30s. Another system will move through Wednesday night and Thursday for above freezing conditions. For now, there’s nothing longer term suggesting a particularly cold pattern on the horizon.
Lows Tonight:
All locations will be above freezing tonight.
Next Report: Friday morning/January 19