November 30, 2019
Summary: Already this afternoon, light precipitation has moved into the valley with measurable rain along the west side of Kern and Kings Counties. As much as a quarter of an inch of rain has been tallied so far along the central California coast from Monterey down into Santa Maria. The old fashioned pineapple connection is setting up across the Pacific underneath a large area of low pressure extending from western Washington to west of the California coast. The heaviest line of moisture will move inland from roughly Madera County northward where in excess of an inch of rain on the valley floor is possible from tonight through Monday. Lesser amounts can be expected further south. If models are correct, the Kern County portion of the valley floor will receive very little as they will be in a strong rain shadow and south of the main dynamics of this storm.
Pressure differences are already setting up between southern California and rapidly falling pressure over the northern California coast. Already this afternoon, winds at the base of the Grapevine are sustained at 16, gusting to 35 MPH. that will slowly increase tonight and Sunday morning. More on this in the wind discussion below.
The center of low pressure will move southward parallel to the central coast Monday night through Tuesday night. the counterclockwise circulation around this storm will cause bands of showers to pinwheel across central California from time to time. On Wednesday, the low will open up and move quickly across southern California with the likelihood of showers into Wednesday evening.
Dry weather will begin later Wednesday night through Thursday night. models still indicate a very impressive trough of low pressure will stretch from the Gulf of Alaska to southern California Friday through Saturday with significant amounts of rain and mountain snow. It’s a bit early to try to guesstimate potential precipitation totals, but it does appear to be a full blown winter storm. Finally, dry weather will return over the second half of the coming weekend. Models continue to indicate a building ridge of upper level high pressure will be over the eastern Pacific and western U.S. for an extended period of dry weather, no doubt leading to our first fog regime.
Forecast: Light rain this evening then periods of rain, locally heavy at times, north of Fresno County later tonight through Monday. Just light showers can be expected in much of the south valley. Showers likely Monday night. a chance of showers Tuesday and Tuesday night. showers likely Wednesday with a slight chance of thunderstorms. Showers diminishing Wednesday evening then partly to mostly cloudy later Wednesday night through Thursday morning. Partly cloudy Thursday afternoon and night. rain spreading over the valley Friday with rain likely Friday night and Saturday.
Short Term:
Madera 43/57/46/59 | Reedley 44/58/46/59 | Dinuba 42/57/45/58 | |
Porterville 44/59/46/61 | Lindsay 42/58/45/60 | Delano 44/58/46/61 | |
Bakersfield 44/61/47/63 | Taft 43/60/48/63 | Arvin 44/62/47/63 | |
Lamont 43/60/47/63 | Pixley 42/59/46/60 | Tulare 41/57/45/58 | |
Woodlake 42/58/46/59 | Hanford 42/58/46/59 | Orosi 42/58/45/59 |
Winds: Winds through Sunday will be out of the east or southeast at 15 to 25 MPH with stronger gusts. In Kern County, downslope winds off the Tehachapi Mountains will range between 15 and 30 MPH with local gusts to 50 MPH possible at the base of the Tehachapi Mountains, especially in places like the bottom of the Grapevine. Winds Sunday night and Monday will be out of the east or southeast at 10 to 20 MPH with stronger gusts. Winds Monday night and Tuesday will continue to be out of the east of southeast at 10 to 20 MPH with stronger gusts.
Rain: As of 1:00PM, Blackwell Corners had recorded .01, Taft .02, and Buttonwillow .03 with several other locations recording trace amounts which no doubt have become measurable as we prepare this report. The first pineapple connection, or as the young guys call it “atmospheric river of air”, has set up across the Pacific and is beginning to affect central California. The first phase of this pattern is moving in a bit further south than even the latest models had projected. However, the deeper tropical moisture is still off shore and is projected to be focused mainly from a Monterey/Merced/Yosemite line north. Even so, significant amounts of rain may fall as far south as Fresno County where between .50 and .75 is likely from tonight through Monday with perhaps a tenth or two over the valley portion of Kern County and .25 to .33 over the valley portion Kings and Tulare Counties. This is also an ideal pattern for orographic precipitation along the Sierra Nevada where two to four inches of rain is anticipated below the 7,000 foot elevation from Fresno County north and much lesser amounts south of that line.
The heaviest precipitation will end by Monday evening, but the chance for showers will continue Monday night through Tuesday night as the center of the storm slides southward off the central coast. Showers and a chance of thunderstorms will pick up Wednesday as the main low tracks across southern California.
Dry weather will return later Wednesday evening and will continue through Thursday night. models continue to show a very significant winter storm moving across the western states this weekend with rain becoming likely Friday through Saturday. dry weather should return over the second half of the weekend and, if models hold, a prolonged period of dry and no doubt foggy weather will follow.
Frost Discussion: All locations will be above freezing tonight and for all of the upcoming week. There’s a slight chance of frost next Sunday and Monday, however, if this occurs at all, only local frost would be likely.
Next report: Sunday morning/December 1