February 22, 2020
Summary: All of the shower activity is concentrated in the south valley, especially in Kern County, at this hour. Over the past hour, a couple of isolated thunderstorms pulsed up. One was located just south of Lamont. The other was near McKittrick. As the low moves through southern California this afternoon, the winds aloft, which are currently out of the north, will become more northwesterly. This will begin to drag drier air into central California, slowly ending the activity over the valley floor this evening. Some models show showers continuing over the southern Sierra and Kern County mountains into early Sunday morning.
By midday Sunday, the center of circulation of this storm will have moved into the Four Corners region. Behind the exiting low will be a large ridge of upper level high pressure. The flow aloft Sunday through Tuesday will be out of the north/northwest, maintaining seasonal temperatures. As we progress through the midweek period, the high will move overhead with a weak westerly flow becoming more dominant. The combination of a warm bubble of subsiding air under that upper high and a mild westerly flow will result in temperatures responding according, moving into the mid to upper 70s. for now, it looks like Friday will be the warmest day of the upcoming week.
A couple of medium range models are suggesting the high will break down during the second half of the upcoming weekend. This would allow a trough of low pressure to move through Sunday, possibly forming a new low pressure circulation system over southern California. Should this happen, it would bring our next chance of rain. Once again, the best chance of precipitation appears to be over southern California. Otherwise, this upcoming week will be a pleasant one with no significant weather challenges after this evening.
Forecast: A chance of showers and isolated thunderstorms through the early evening hours, mainly in Kern County and along the Sierra Nevada foothills. Clearing later tonight. mostly clear Sunday and on through to Saturday of next week.
Winds: Winds this evening will be mainly out of the northwest at 5 to 12 MPH with stronger gusts in the vicinity of showers. From later tonight through Tuesday, winds will be generally at or less than 10 MPH late mornings and afternoons and less than 6 MPH with periods of near calm conditions during the night through mid morning hours.
Rain: West Porterville has recorded .21, northwest Bakersfield .10, Visalia and Tulare each report .01. most other locations have had no measurable precipitation as of 1:30pm. Between rain gauges, however, there were a couple of brief thunderstorms that resulted in brief, heavy rain. One storm percolated up south of Lamont and another near McKittrick. Each has dissipated. The chance of showers and isolated thunderstorms will continue through the early evening hours, mainly in Kern County and along the Sierra Nevada foothills. Although most locations will record no measurable rain, isolated locations could pick up .10 to possibly as much as .25 where thunderstorms occur. Even some small hail would not be a total shock. Dry weather will return later tonight and this will be the theme for all of the coming week. For the second model run in a row, the GFS model is indicating a trough of low pressure strong enough for showers will move through about Sunday might through Monday of next week, possibly forming a low center over southern California, which has been a fairly common theme this winter.
Frost Discussion: Above freezing conditions will continue indefinitely.
Next report: February 23/morning