November 25, 2017
Summary: Temperatures this afternoon are again approaching record levels. Many locations are already in the low to mid 70s, meaning a few locations in Kern County may top the 80 degree mark this afternoon. A very warm air mass is already in place. Now we have a weak southerly flow developing along a digging trough of low pressure off the Pacific Northwest and northern California. This trough will begin to shift eastward into northern and central California Sunday, spreading rain down to a Bay Area/Stockton line by possibly sunrise Sunday with light showers spreading down the valley during the afternoon and evening.
The vast majority of the precipitation will be along the Sierra Nevada due to lift. A strong west/southwest flow accompanied by the jet stream will move overhead Sunday night for significant precipitation over the higher elevations. The backside of the trough will move through Monday morning, so most, if not all, the precipitation should come to an end no later than midday Monday. With a strong northwest flow behind the trough, upslope clouds will rapidly develop along the west facing slopes of the Sierra Nevada and even more so along the north facing slopes of the Kern County mountains. Clearing will begin mainly along the west side Monday afternoon, slowly encroaching on the remainder of the valley. However, it may be sometime Tuesday before Kern County clears.
Temperatures will take a significant drop so that the weather will feel like late November instead of early October.
Looking ahead to the middle to latter part of next week, it looks like the next low will slide southward too far off shore to have much impact on our weather. It appears the next chance of precipitation may be seven to eight days down the road as the next, more significant trough, shows up on paper. The biggest challenge next week may be increasing amounts of morning fog and low clouds, which is typical for this time of year.
Forecast: Becoming partly cloudy overnight. Increasing cloudiness Sunday. Light showers spreading down the valley late Sunday afternoon and evening, possibly reaching Fresno County by midday or so and Kern County by late afternoon and evening. Light showers Sunday night into Monday morning. Mostly to partly cloudy Monday afternoon through Tuesday morning. Mostly clear to occasionally partly cloudy Tuesday afternoon through Saturday with areas of night and morning fog.
Short Term:
| Madera 50/74/54/64 | Reedley 49/75/54/65 | Dinuba 49/74/53/64 | |
| Porterville 49/77/53/65 | Lindsay 49/77/54/64 | Delano 50/78/55/65 | |
| Bakersfield 55/81/56/65 | Arvin 53/81/55/64 | Taft 56/79/56/66 | |
| Lamont 53/80/55/63 | Pixley 49/78/55/65 | Tulare 49/75/54/64 | |
| Woodlake 50/76/54/63 | Hanford 49/76/54/63 | Orosi 49/77/55/65 | |
Winds: Winds will be generally less than 10 MPH tonight with periods of near calm conditions. Winds Sunday will be out of the southeast at 5 to 15 MPH, increasing to 10 to 20 MPH from roughly Fresno County northward with stronger gusts during the afternoon and nighttime hours. Winds will be out of the northwest Monday at 10 to 20 MPH with stronger gusts at times, diminishing Monday evening and becoming light after midnight. Expect light winds Tuesday.
Rain: Models continue to have some timing issues with this incoming system. My best guesstimate at this time would be to see light showers spread into Fresno County about midday Sunday then spread southward, reaching Kern County during the later afternoon to evening hours. Light showers will be likely especially along the east side north of Kern County Sunday night through about midmorning Monday. Expect dry conditions Monday afternoon, continuing through at least Saturday of next week.
A trough passage may occur about Saturday night or Sunday, but for now there’s not enough to go on for more specifics.
Frost Information: All locations will be well above 32 degrees tonight and each night through Monday morning. I haven’t really changed my tune much on this colder air mass that will be moving in from the northwest beginning Monday. Anytime from Tuesday morning on, where it clears, mid to upper 30s will be possible in the colder locations. Modeling has done somewhat of a switch for the middle to latter part of next week. A weak westerly flow will develop, precluding any chance of cold air filtering into the valley. In the medium range, there’s nothing on paper to suggest a particularly cold pattern on the horizon.
Next Report: Sunday morning, November 26