Subj : MESO: Mesoscale Discussion 0180 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Mar 01 2024 00:51:47 ACUS11 KWNS 010051 SWOMCD SPC MCD 010051=20 CAZ000-010445- Mesoscale Discussion 0180 NWS Storm Prediction Center Norman OK 0651 PM CST Thu Feb 29 2024 Areas affected...Portions of the Sierra in northern California Concerning...Heavy snow=20 Valid 010051Z - 010445Z SUMMARY...Snowfall rates are expected to increase to near 2-3 inches per hour with localized blizzard conditions across portions of the Sierra in northern California in the 01-06Z time frame. DISCUSSION...Within the base of a deep midlevel cyclone centered off the British Columbia coast, the exit region of a robust mid/upper-level jet streak will impinge on the northern Sierra during the next few hours, while a related cold front moves southeastward across the region. The associated increase in large-scale ascent/frontal forcing, augmented by strengthening upslope flow, will continue to favor an increase in precipitation rates into tonight. This increasing ascent is already becoming evident in low/mid-level water-vapor loops and regional radar data. Given the overlap of strengthening ascent and influx of Pacific moisture (including a relatively deep and saturated dendritic growth zone), snowfall rates are expected to increase to near 2-3 inches per hour over portions of the northern Sierra (with locally higher rates possible). Current thinking is that these heavier rates will become more persistent in the 01-06Z time frame as the cold front continues southeastward (supported by the latest high-resolution guidance), with heavy snow persisting into the overnight hours. The highest rates will likely occur at elevations above 5000-6000 feet.=20 In addition, strengthening low-level flow accompanying the mid/upper-level speed maximum and cold front will likely support localized blizzard/whiteout conditions, given the potential for 50+ mph gusts and the heavy snowfall rates. ...Weinman.. 03/01/2024 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!4YL0j5APCM-dXnUrgBhN_r3FREy29ymcSbDqxDwLIfiT2fF0ikND--8bKvFwEe2QGv3rN8_5B= LLL9AoYMIR5KtbyC8c$ for graphic product... ATTN...WFO...REV...HNX...STO... LAT...LON 38221950 38021972 38242005 38922046 39492080 39712112 39912108 40022080 39652042 38681989 38221950=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .