January 17, 2020
Summary: Temperatures, as of 1:00pm, were running anywhere from 6 to 16 degrees colder than 24 hours ago. A few locations towards the center of the valley were still reporting fog and low clouds. The Lemoore Naval Air Station was reporting just 43 degrees, Hanford 46, and most others in the lower 50s. vThe latest freezing level above Vandenberg Air Force Base was just 3,400 feet, so the air mass both on the valley floor and aloft remains cold. Dew points are still fairly high, however, and are generally in the low to mid 40s. radiational cooling after the sun goes down will allow temperatures to reach the dew point. This will no doubt renew fog and low clouds overnight into Saturday morning. where the fog doesn’t take over, chilly temperatures will be the result, something detailed in the frost discussion below.
A flat zone of upper level high pressure now extends from the eastern Pacific eastward into California while weak high pressure has developed over the Great Basin, resulting in a weak off shore surface flow. With the westerly flow aloft, warmer air will move in above the valley floor over the weekend, resulting in an increasing warm air inversion which will support the previously alluded to fog and low clouds. It’s possible, especially Sunday and Monday, that some locations may not see the sunshine even during the afternoon hours.
The next Pacific storm will begin to impact central California late Monday night through Tuesday night. There remains quite a few differences of opinion on models regarding this system’s potential. The GFS model continue to nudge the precipitation line further north, indicating light showers down to about Fresno County. The European Model tries to develop a tropical connection, in which case precipitation would be heavier and much further south. Models do agree that beginning Wednesday, a stronger ridge of upper level high pressure from the eastern Pacific will build into the western U.S. for rain free weather and, no doubt, plenty of night and morning fog.
Forecast: Widespread fog and low clouds developing tonight and Saturday morning with partial afternoon clearing. Expect the same Saturday and Sunday nights with partial afternoon clearing again Sunday and Monday. Increasing cloudiness Monday night with a chance of showers Tuesday and Tuesday night. a slight chance of showers early Wednesday morning, otherwise it will be mostly to partly cloudy Wednesday. expect extensive areas of night and morning fog with some afternoon clearing Thursday through Friday.
Short Term:
Madera 30/54/31/55 | Reedley 31/55/32/56 | Dinuba 29/53/31/55 | |
Porterville 30/54/31/58 | Lindsay 30/54/31/58 | Delano 31/55/32/59 | |
Bakersfield 35/57/36/60 | Taft 38/57/39/60 | Arvin 32/57/33/60 | |
Lamont 31/56/32/59 | Pixley 31/54/31/58 | Tulare 30/53/31/55 | |
Woodlake 31/54/31/56 | Hanford 32/54/33/56 | Orosi 30/54/31/56 |
Winds: Winds will be at or less than 6 MPH through Monday with periods of near calm conditions.
Rain: Dry weather will continue through at least the late evening hours Monday night. there is a slight chance of showers late Monday night with a higher risk Tuesday and Tuesday night. there are many model differences on both the track and potential precipitation amounts. One model moves rain no further south than Fresno County while another indicates a subtropical connection which would increase the chance of precipitation dramatically. One thing models do agree on is that from Wednesday of next week through the following weekend, the weather will be dry.
Frost Discussion: It is quite chilly out there this afternoon with temperatures ranging only in the mid 40s where fog has yet to dissipate to the low 50s where the sun has poked through. The air mass now settling to the bottom of the San Joaquin Valley is cold, but not critically so. Warmer air will begin to move in aloft tonight, setting up a warm air inversion which will help the fog machine get revved up and no doubt become widespread by Saturday morning. where it remains clear, unprotected low lying regions could drop down to 28 to 29 degrees with most flatland areas ranging from 30 to 33 with hillsides marginally above freezing. Keep in mind also, where and when fog develops, right along the edge of the fog bank may be a short lived dip in temperatures which typically move back up again as soon as the fog and low clouds take over. Upper 20s to low to mid 30s are likely again Sunday and Monday mornings unless the fog completely takes over and lifts into o9ur protective low cloud deck above the valley floor. If this occurs, readings will be above freezing. Increasing higher clouds and a moderating air mass will maintain above freezing conditions Tuesday and Wednesday mornings. Models also indicate a stronger ridge of high pressure will take over Wednesday through next weekend, resulting in above average temperatures unless we move into a full fledged fog regime. In that case, we’d have below average daytime highs with above average nighttime temps.
Lows Tonight:
Terra Bella
31 |
Porterville
31 |
Ivanhoe
29 |
Woodlake
30 |
Strathmore
30 |
Mcfarland
29 |
Ducor
31 |
Tea Pot Dome
30 |
Lindsay
29 |
Exeter
29 |
Famoso
31 |
Madera
30 |
Belridge
29 |
Delano
31 |
North Bakersfield
31 |
Orosi
29 |
Orange Cove
30 |
Lindcove
29 |
Lindcove Hillside | Sanger River Bottom
27 |
Root Creek
29 |
Venice Hill
30 |
Rosedale
31 |
Jasmine
30 |
Arvin
31 |
Lamont
31 |
Plainview
30 |
Mettler
32 |
Edison
32 |
Maricopa
33 |
Holland Creek
32 |
Tivy Valley
29 |
Kite Road South
32 |
Kite Road North
29 |
AF=Above Freezing
Next report: January 18/morning