Doppler HNX showing frontal boundary moving thru, extending from Sonora southward thru Merced to near SLO. There have been several Meso-type signatures on radar this evening, and several Tornado Vortex Signatures, (TVS) which is depicted upon the radar image below with the pink triangle near Dinkey Creek. Note the small line of echoes over Pacheco Pass in western Merced Co …which represents a new line of thunderstorms developing in an environment favorable for growth…cold air, and several favorable Convective Parameter.
Precip totals over CENCAL thus far this evening at 10pm range from 4.17 inches along the Central Coast at Three Peaks in southern Monterey Co, 3.90 Mining Ridge, 2.84 Venado 2.50 Ben Lomond, 2.24 Anderson Peak, 1.88 Fort Dick, 1.56 Santa Rosa, 1.52 Honeydew, 1.46 San Bruno, 1.44 Taylor Ridge, 1.40 Shasta Dam, 1.20 DeSabla, 1.00 Cambria, 0.96 Wawona, 0.93 La Porte, 0.91 SF, 0.77 Bass Lake, 0.74 Shaver Lake, 0.69 Dinkey Crk, 0.66 SJ, 0.54 Blue Cyn, 0.50 Alpine Mdws, 0.47 Oroville, 0.45 OAK and Wishon Dam, 0.43 YNP, 0.39 Elk Grove, 0.37 Buchanan, 0.35 Merced, 0.33 Balch Camp, 0.30 Modesto, 0.25 Buck Rock, 0.23 Shadequarter and Wolverton, 0.20 SAC, Madera, Friant, Cedar Grove, 0.18 Fresno, 0.14 Milo, 0.12 Hanford, Oak Opening. 0.10 Stockton,
HNX Doppler 10:30pm showing the frontal boundary moving thru, with a narrow break behind the front with another convective line forming over Pacheco Pass.
SAC Doppler 10:30pm showing the frontal boundary wrapping to the NW with many MESO signatures
Monterey Doppler showing a Supercell Thunderstorm nearing SJ. Cell “R2” is rotating and moving NE with a MESO signature and a dBz reflectivity of 60 and indicating 0.5 inch sized HAIL.
Water Vapor Image showing the frontal boundary moving thru the Great Valley and into the Sierra, followed by a narrow DRY SLOT, and then more convective showers developing along the backside of the DRY SLOT.
Convective Parameter; CAPES showing values of 100 to 250 joules/kg entering the Great Valley with CAPES of 500 joules/kg moving onshore over the Bay region.
Convective Parameters; Supercell showing values of 1 from western Merced Co northward to near SAC.
Convective Parameter; Significant Tornado showing a value of 10 to 20 from western Fresno Co northward into the SAC Valley.
500mb chart showing a 70kt vortmax aimed at Santa Maria with a -25°C cold core approaching San Francisco with cold air advection pouring into CENCAL aloft…destabilizing the atmosphere.
700 chart showing cold air advection into CA with -7°C temps nearing the coast with a 50kt SW flow pattern
CONCERN FOR FRIDAY Convection;
Charts are looking favorable for an early day event on Friday,
CRAVEN PARAMETER looks high for the SJV
Significant Tornado Parameter is showing on the lower end of the scale, but its there!
Another Significant Tornado Parameter (Old) showing the SJV cover with a low end of the scale value
Supercell Parameter showing moderate values for the SJV
Significant Hail Parameter showing the Westside SJV with larger sized HAIL.