NGUS86 KRSA 231508 HCMRSA Hydrometeorological Coordination Message National Weather Service / California Nevada RFC / Sacramento CA 710 AM PST Sat Nov 23 2024 ...SCATTERED PRECIP TODAY AS COLD FRONT AND MOISTURE SLIDE SOUTH... ...NEXT ROUND OF PRECIP FOR LATE SUNDAY INTO TUESDAY... ...DRYING WEDNESDAY INTO THANKSGIVING DAY... .METEOROLOGICAL CONDITIONS (SAT AM - FRI AM)... Overnight...the cold front continued to press inland and southward while also weakening as it became separated from the more favorable forcing to the north. The associated moisture plume is nearing Point Conception with advection of the PW inland toward the southern Sierra. Looking at the 23/12Z RAOB from Vandenberg...where the moisture plume was located at the time of balloon launch...PW was recorded at 1.30-inches. Radar imagery indicates echoes along and ahead of this frontal boundary moving across north-central and northeast NV back across the southern Sierra and eventually the southern San Joaquin Valley and locations near Point Conception. Behind the frontal boundary are focused areas of showers moving through the cyclonic flow aloft and individual disturbances rotating across northern CA. Through today...the moisture plume will continue to press toward the south and cross the CA/MX border during the afternoon hours. Precip with this feature will continue to dissipate with only light amounts expected from Los Angeles down to San Diego...0.25-inch or so for the higher terrain and about 0.10-inch or less at the lower elevations. Back north...scattered precip will continue in the cooler airmass under cyclonic flow aloft. Freezing levels will slowly drop as the cooler airmass settles in across the area today into early tomorrow...bottoming out from 4000- to 5500-feet from the I-80 corridor northward and then 6000- to 11500-feet across central and southern locations. Sunday will start primarily dry but will transition to the next round of precip to affect the region as the upr low off the Pacific Northwest coast begins to make its way toward the coast as an open wave down across northern CA on Monday into Tuesday. For central CA...the next moisture plume from a source along 30N will arc northeast to and focus on an area somewhere south of the Monterey Bay to Point Conception. Peak PW values within this feature are actually fairly impressive...at or just above 1.50-inches. This will spread moderate precip across areas between the Santa Cruz Mountains down to Point Conception and then inland over the central/southern San Joaquin Valley and adjacent Sierra with anywhere from 0.50- to 1.00-inch at lower elevations and 1.00- to 3.00-inches over the higher terrain. Tuesday sees this moisture plume continue to take aim at the central CA coast with decent transport inland for another 0.50- to 1.00-inch at lower elevations and 1.00- to 3.00-inches over the higher terrain. This puts storm totals in that range of 1.00- to 6.00-inches with the best from the upper San Joaquin River basin south through the Tule and portions of the Kern River basin. Freezing levels during a majority of this event will range from 8000- to 11000-feet from north-to-south across central CA. By Wednesday...the northern s/wv trof will move inland toward the central Rockies and the moisture plume will get shunted to the south. Look for a transitory upr ridge to slide across the area on Wednesday into Thanksgiving for dry conditions. Some models hint at a disturbance approaching the coast from the west-southwest late Thanksgiving into Friday...but at this time there is a lot of discrepancies with the models...and kept things dry for now. QPF graphics are available at www.cnrfc.noaa.gov/qpf.php *********************** Contact Information ************************ CNRFC Office Hours Phone: 1 (916) 979-3056 Extension 338 After-Hours Calling Service: 1 (800) 218-0858 Leave Name...Office...and Phone Number Kozlowski $$