December 4, 2019
Summary: The main frontal band has now moved into the Sierra Nevada and is accelerating towards the east. The main upper low is now crossing the southern San Joaquin Valley at its time of maximum daytime heating. With the warmth of what is a weak December sun destabilizing the atmosphere, isolated thunderstorms are a good bet this afternoon through the early evening hours. In fact, several lighting strikes have already shown up on radar in western Kings County.
Rainfall amounts have exceeded expectations in many areas with some locations recording more than .50. individual rainfall amounts are detailed below.
The main area of low pressure will finally move into Nevada this evening, bringing a halt to the showers and thunderstorms. A temporary ridge of upper level high pressure will build in from the west later tonight for dry weather later tonight through at least Friday morning.
The next low is already developing in the southern Gulf of Alaska and will drop south/southeast to a position just off the northern California coast by Saturday morning. The flow around the bottom of the low will be out of the west/southwest right into central California for the usual rain shadows along the west side and in Kern County Friday night through Saturday night. the low and its associated trough will move through central California Sunday, maintaining a good chance of showers during the day Sunday, ending by Sunday evening.
A massive ridge of upper level high pressure will build northward right along the north American continent, reaching as far north as the Arctic Circle. Fortunately, this high will be right over head Monday and Tuesday as arctic air dives southward into the Rocky Mountain region, fortunately too far to the east to threaten subfreezing weather.
A weak low will move through southern California Wednesday of next week, but for now it looks like it will be too weak for precipitation. With high pressure dominating next week, the necessary warm air inversion will develop above the valley floor for widespread fog and low clouds nights and mornings with partial afternoon clearing.
Forecast: Scattered showers and a chance of thunderstorms this afternoon through the early evening hours. Showers ending this evening. Becoming partly to mostly cloudy later tonight into Thursday morning with areas of fog and low clouds later tonight and Thursday morning. Partly cloudy Thursday afternoon. Becoming mostly clear Thursday night with widespread fog and low clouds developing into Friday morning. Increasing cloudiness on Friday with a chance of showers from Fresno County north Friday afternoon. Periods of rain Friday night through Saturday night. showers likely Sunday with a slight chance of isolated thunderstorms Sunday afternoon. Partly to mostly cloudy Sunday night and Monday morning with areas of fog and low clouds Monday morning. Widespread fog and low clouds nights and mornings Monday night through Wednesday with partial afternoon clearing.
Short Term:
| Madera 41/61/41/64 | Reedley 42/62/43/64 | Dinuba 40/61/42/63 | |
| Porterville 41/62/42/65 | Lindsay 40/62/42/65 | Delano 44/63/45/65 | |
| Bakersfield 46/64/48/66 | Taft 47/62/48/65 | Arvin 44/63/45/65 | |
| Lamont 44/63/45/65 | Pixley 43/63/43/64 | Tulare 41/61/42/63 | |
| Woodlake 41/62/42/64 | Hanford 41/62/42/64 | Orosi 40/62/41/63 | |
Winds: Winds this evening will be mainly out of the southeast at 5 to 15 MPH with stronger gusts near showers and thunderstorms. Winds later tonight through Thursday night will be generally at or less than 7 MPH with periods of near calm conditions. By Friday afternoon, winds will be out of the southeast at 10 to 15 MPH, increasing to 15 to 25 MPH Friday night and at times through Saturday night with stronger gusts.
Rain: The following are storm totals as of 1:00pm. Bakersfield .20, Mettler .08, Taft .35, Arvin .28, Lamont .22, Buttonwillow .10, Shafter .52, Delano ,48, Porterville .46, Exeter .57, Tulare .42, Stratford .36, Lemoore .35, Hanford .42, Visalia .46, Parlier .41, Del Rey.40, Fresno .31, Clovis .52, Firebaugh .62.
The main rain band associated with the cold front is now to our east. For the rest of the afternoon through the evening, we’ll be dealing with the main body of low pressure which is moving directly over the south valley during the time of maximum daytime heating. Even though the sun angle is very low, and is at its weakest, the air mass should be unstable enough to trigger isolated thunderstorms this afternoon and evening along with triggering numerous showers. The low will finally dump into Nevada later this evening for a return to dry weather which will continue through at least Friday morning.
There will be a minimal chance of showers as early as Friday afternoon from Fresno County north, becoming likely by Friday night and at times through Saturday. showers will continue Sunday with at least some chance of isolated thunderstorms again Sunday afternoon.
Dry weather will return Sunday night. models show dry weather through what looks like all of next week.
Frost Discussion: All locations will be above freezing for at least the next seven to ten days.
Next report: Thursday morning/December 5