Author: Trudy Hibler

May 11, 2022 It was a chilly morning out there. The coldest readings I could find as of 6:00am were 36 at east Porterville and 37 at Terra Bella and Lindsay. Most other locations were between 39 and 44. The center of circulation of a cold upper low is right overhead this morning. It will…

May 10, 2022 At the upper levels of the atmosphere, a cold low extends from southcentral Canada to a second center just off the northwest California coast. For the second day in a row, the balloon sounding taking just a bit ago off Oakland was 3,700 feet. At the surface, pressure is still considerably lower…

May 9, 2022 Temperatures for the next 72 hours will run anywhere from 10 to 15 below average. A very cold upper low is located off the northwest California coast this morning with a mostly dry trough of low pressure extending southward into central and southern California. The balloon sounding above Oakland this morning pegged…

May 7, 2022 At the upper levels of the atmosphere, a mammoth trough of low pressure is digging slowly southward into California. At the surface, a deep area of low pressure is setting up shop over southern Nevada. The current altimeter reading at San Francisco is 30.09 inches of mercury while at Las Vegas the…

May 6, 2022 Upper level high pressure is slowly breaking down and is sagging southward from its center off the coast of the Pacific Northwest. The marine layer is slowly deepening and is surging through the Delta. That modified sea breeze will eventually spill over other gaps and passes along the Coast Range further south.…

May 5, 2022 The northern portion of the ridge of upper level high pressure which has driven temperatures into the lower 90s is breaking down. We should see one more day of lower 90s before a significant cooling trend begins Friday. Already this morning, the marine layer has deepened and is moving through the Delta.…

May 4, 2022 Relatively strong upper level high pressure will be right above California during the next 48 hours. At the surface, there is a very weak off shore flow, just enough to combine for a very warm day as readings trend upwards to around 12 degrees above average. This puts most locations in the…

May 3, 2022 Currently, a ridge of upper level high pressure is building eastward over California with a ridge extending inland into Washington and Oregon. The low is now located over eastern Utah. A strong ridge of upper level high pressure will build over the west coast over the next 48 hours, pushing temperatures into…

May 2, 2022 A trough of low pressure is currently moving into the Pacific Northwest and will dive into the Great Basin this afternoon and tonight. The difference in pressure between San Francisco and Las Vegas is currently just around 5 millibars, but will increase tonight to around 12 to 15 millibars. Already there is…

April 30, 2022 a low pressure system will move into the Pacific Northwest later today, too late, however, to allow an intrusion of air into the valley. But, as the low moves into the Great Basin Sunday, the marine layer will deepen more as the difference in pressure between the coast and the interior increases.…