December 5, 2023
Summary: Relatively strong upper level high pressure has shifted further east and is now centered over northern Arizona while a trough of low pressure approaches the coast of the Pacific Northwest. Pressures are higher over the interior west than they are off shore. This will result in downslope heating off the northern slopes of the Tehachapi Mountains and the west facing slopes of the Sierra Nevada. This, in part, will drive temperatures to record highs Wednesday with readings well into the 70s. Upper 70s cannot be ruled out over Kern County. That trough of low pressure off shore will swing through northern and central California Wednesday night and Thursday morning. The latest high resolution models indicate that there may be enough dynamics left over for a small chance of sprinkles or scattered light showers from Fresno County north Wednesday night and early Thursday morning. The rest of the valley will observe variable cloudiness and much cooler weather Thursday and Friday. Frost is again back in the forecast beginning Friday morning. This is discussed below in the frost summary. A new ridge of high pressure will build in from the west beginning Friday and will continue to shift overhead through the weekend and into early next week. This will lock in a typical December air mass on the valley floor with cool days and chilly nights. There is still nothing on modeling information that would break the pattern we’ve seen this fall. So, outside of a few raindrops Wednesday night and Thursday morning from Fresno County north, the rest of the week looks dry.
Forecast: Mostly clear tonight with patchy fog after midnight. Mostly clear after patchy fog burns off Wednesday morning. Partly cloudy Wednesday afternoon. Variable cloudiness Wednesday night and Thursday with a small chance of scattered light showers from Fresno County north Wednesday night and Thursday morning. Partly cloudy Thursday afternoon into Friday morning. Mostly clear Friday night and on through Tuesday with patchy night and early morning fog.
Short Term:
| Madera 39/74/40/59 | Reedley 40/75/40/60 | Dinuba 38/73/40/59 |
| Porterville 39/76/40/59 | Lindsay 38/74/39/59 | Delano 41/76/40/58 |
| Bakersfield 44/76/45/58 | Taft 52/74/50/57 | Arvin 43/77/43/61 |
| Lamont 43/75/41/60 | Pixley 41/76/40/60 | Tulare 39/74/39/58 |
| Woodlake 39/74/40/59 | Hanford 40/75/41/61 | Orosi 39/73/41/61 |
Winds: Winds through Wednesday will be generally at or less than 5 mph with period of near calm conditions. From late Wednesday night through Friday, winds will be generally out of the west to northwest at 8 to 15 mph. local gusts to 25 mph are possible Thursday. Winds will decrease by Friday afternoon with light winds returning by Friday evening.
Rain: Latest high resolution models are indicating there may be enough energy to sustain enough energy for sprinkles and light showers down to roughly Fresno County Wednesday night and Thursday morning. The chance of measurable rain even from Fresno County north remains low. After this system moves through, high pressure will again take over for a return to dry weather for the next week and possibly longer.
Frost: All locations will be above freezing Wednesday and Thursday mornings. A colder air mass will overspread the valley Wednesday night and Thursday. Spotty frost could occur as early as Friday morning. However, for Saturday through Monday mornings, upper 20s and lower 30s are likely. This air mass is very similar to the one we recently experienced which lowered temperatures down to 27 to 28 in coldest locations and 29 to 32 elsewhere. I consider this a typical December air mass. The good news is that the dominant pattern for the next week to ten day is for some variety of a north to northwest flow. This cuts off arctic air masses from migrating south, so for now the next ten day period appears safe from overly cold weather.
Lows Tonight:
| Terra Bella af | Porterville af | Ivanhoe af | Woodlake af |
| Strathmore af | mcFarland af | Ducor af | Tea Pot Dome af |
| Lindsay af | Exeter af | Famoso af | Madera af |
| Belridge af | Delano af | North Bakersfield af | Orosi af |
| Orange Cove af | Lindcove af | Lindcove Hillside af | Sanger River Bottom af |
| Root Creek af | Venice Hill af | Rosedale af | Jasmine af |
| Arvin af | Lamont af | Plainview af | Mettler af |
| Edison af | Maricopa af | Holland Creek af | Tivy Valley af |
| Kite Road South af | Kite Road North af |
AF=Above Freezing