January 18, 2019
Summary: Most parts of the valley are enjoying a bit of sunshine this afternoon. The exception so far is portions of the valley region of Kern County which remain under a low overcast. The latest observation at Bakersfield indicated the low cloud deck is at 1,000 feet at Meadows Field. Dew points this afternoon are very high, ranging in the low to mid 50s. With clear to partly cloudy skies, temperatures will have no problem falling to the dew point with widespread ground fog forming, possibly lifting into a low overcast Saturday with partial afternoon clearing. That same rule of thumb will apply to Saturday night and Sunday morning, as well.
Weak upper level high pressure centered well off the southern California coast has driven the storm track back up into the northern one-third of California. The rain line will continue to migrate a bit further north.
In the short term, warmer air aloft is certainly moving in. the freezing level has jumped up to 11,000 feet above Vandenberg while over Oakland, the freezing level is just 6,200 feet. Temperatures will rise into the 60s both Saturday and Sunday, assuming fog and low clouds don’t completely take over. Clouds will increase Sunday afternoon ahead of one more trough of low pressure which will spread precipitation over northern and central California Sunday night and Monday morning. Rainfall amounts will be quite light, probably no more than a tenth or two on the valley floor. As this system moves into the Great Basin, the winds aloft Monday night and Tuesday will briefly be out of the north. Couple that with an off shore flow and it could possibly scour out the valley of its low level moisture, possibly leading to local frost Tuesday and Wednesday mornings. This is discussed below.
Beginning Tuesday, a massive ridge will build northward along the North American continent and will encompass the western one-third of the U.S. This high will efficiently create a warm air inversion, setting the stage for increasing amounts of fog and low clouds by midweek and beyond. Above the valley floor, temperatures will rise to well above average.
Medium range models for late next week through the following week continue to indicate a very large blocking ridge will be in place for a prolonged period of dry weather. Some models are showing the arctic air we’ve been discussing east of the Rockies, spilling into the Great Basin with even a slight chance of this air making its way into California. For now, we’ll keep that scenario out of the forecast, but we will diligently be watching.
Forecast: Mostly clear to partly cloudy tonight with widespread fog developing after midnight. Widespread fog and/or low clouds Saturday and Sunday mornings with some clearing Saturday afternoon. Increasing higher clouds Sunday afternoon leading to the likelihood of light rain Sunday night and Monday morning. Mostly to partly cloudy Monday afternoon through Tuesday morning. Mostly clear Tuesday afternoon through Friday but with increasing amounts of night and morning fog and low clouds.
Short Term:
| Madera 42/58/43/62 | Reedley 42/59/44/62 | Dinuba 42/58/44/61 | |
| Porterville 43/61/44/63 | Lindsay 41/61/44/63 | Delano 44/63/44/64 | |
| Bakersfield 47/62/48/66 | Taft 48/63/48/67 | Arvin 48/63/48/67 | |
| Lamont 45/63/48/66 | Pixley 42/63/44/63 | Tulare 42/60/44/62 | |
| Woodlake 42/60/43/61 | Hanford 44/62/43/62 | Orosi 42/60/43/62 | |
Winds: Winds will be generally less than 6 MPH through Sunday morning with periods of near calm conditions. Winds Sunday afternoon will be out of the southeast at 5 to 15 MPH, continuing Sunday night. Winds Monday will be out of the northwest at 10 to 20 MPH with stronger gusts possible along the west side.
Rain: The chance of light rain will increase Sunday evening with periods of light rain Sunday night and Monday morning. This system pales in comparison to other recent storms and will probably drop no more than a tenth or two at most locations. Dry weather will return Monday afternoon, beginning a long period of dry weather through the remainder of next week and, if models are correct, possibly through the end of January.
Frost Discussion: All locations will be above 32 degrees tonight and each night through Monday morning. Models now show a north/south flow developing behind a weather system which will move through Sunday night and Monday morning. We may see some gusty, northwesterly winds Monday afternoon, possibly scouring out the valley’s low level moisture. If this happens, we would see widespread low to m id 30s as early as Tuesday morning with a chance of upper 20s in unprotected river bottom and like locations. That same rule of thumb will apply for Wednesday and possibly Thursday mornings. The other solution is low level moisture remains in the eastern and southern flanks of the valley in the form of upslope clouds against the Sierra and the Kern County mountains, which would keep temperatures largely above freezing. At any rate, this is by no means a dangerous situation.
Models still show some modified arctic air spreading into the Rockies and Great Basin Thursday and Friday of next week with a slight chance of some of this air spilling into California. Currently, there’s about a 90% chance of this air remaining east of the Sierra Nevada, thus maintaining safe conditions. Still, this is somewhat of a deviation from earlier models and bears close scrutiny.
Next report: Saturday morning/January 19