A Series Of Western Storms Will Just Dump On The Sierra Nevada!
National Blend Of Models (NBM) 5-day Storm Total Precipitation Forecast.
A Series Of Western Storms Will Just Dump On The Sierra Nevada!
Over the next week, a series of powerful Western U.S. winter storms will just dump on the Sierra Nevada Mountains and nearby areas. This is one of those events that you just sit back and marvel at...and one for the record books too!
Over the course of the next five days (today through next Monday morning) the National Blend of Models (NBM) is forecasting 129" of snowfall (just short of 11 feet) and nearly 12" of rain for areas highlighted above. Through in some mountain wind gusts of 85 mph at the higher elevations and you have the makings of a historic set of winter storms...blizzards.
Over the course of the next five days (today through next Monday morning) the National Blend of Models (NBM) is forecasting 129" of snowfall (just short of 11 feet) and nearly 12" of rain for areas highlighted above. Through in some mountain wind gusts of 85 mph at the higher elevations and you have the makings of a historic set of winter storms...blizzards.
This Mornings Reno, NV Area Forecast Discussion (AFD).
Area Forecast Discussion National Weather Service Reno NV 231 AM PST Wed Dec 22 2021 ...MAJOR TRAVEL DISRUPTIONS THROUGH THE HOLIDAY WEEKEND... .SYNOPSIS... Stormy weather continues this with rain and snow, mainly for the Sierra and northeast California. Be prepared for major travel disruptions and delays over Sierra passes, especially Thursday. Be prepared for winter travel conditions as heavy snow will continue in the Sierra through most of the holiday weekend, with chances for accumulating snow down into western Nevada valleys Friday. && .SHORT TERM (Through Wednesday Night)... The main message remains the same, "Travel across the Sierra will be difficult to impossible at times through the holiday weekend". . Snow which had already started over NE California and progress south into the higher elevation areas around the Lake Tahoe Basin. Impacts over Donner Summit/Carson Pass should continue through Wednesday into Thursday morning. This first system is the short delay of colder air and precipitation into the West Coast as the upper trough splits and flattens the upper ridge that stubbornly shifts east in the central Rockies. Much of the stronger forcing will lift northeast into OR, but enough forcing will remain to complement the weak isentropic lift into the Sierra, northeast CA, and for northwest NV. Snow levels may start low this morning at ~4500-6000 feet as precipitation moves into the region with colder air still trapped in many valleys. Through Wednesday, a gradually increasing southerly flow may push snow levels as high as 7000-7500 feet over the much of the Sierra south of I-80 to include the Lake Tahoe Basin. The rising snow levels may only bring light snow to the lower elevations of NE California and the Tahoe Basin. Snow levels are currently expected to peak Wednesday afternoon below descending slowly through Wednesday night into Thursday morning. Above about 7000` we should still see around foot or so of new snow with more on the way. Although much the Reno area will be largely spared during this first winter system, most areas below 6000 feet will see mostly rain. But there is a slight chance surrounding higher foothill areas could receive up to an inch of accumulated snow early Thursday morning as snow level start to slowly inch across the region. In western Nevada, expect breezy winds over most areas with increased chances of rain showers spreading into the rest of Western Nevada Wednesday afternoon through Thursday as this first impulse moves further inland. Winds across the Sierra crest will be howling from the southwest 75-85 mph. -Amanda .LONG TERM (Thursday Onward)... ...Main Takeaways Upfront... 1. The forecast remains on track to see several rounds of significant snowfall, eventually spreading into Western NV by Friday. 2. Major travel impacts with very long delays and possible road closures across Sierra and NE California passes. Hazardous driving conditions may persist over higher elevation roadways even if temporary breaks in snowfall intensity occurs. Chain controls are almost guaranteed, so do not attempt traversing the Sierra through early next week without being properly prepared for winter weather. 3. Check your flight status regularly and be sure your patience is packed in the suitcase. Consider downloading apps for CALTRANS and NDOT (QuickMap and NVRoads, respectively) and frequently check road conditions before venturing out. 4. While spillover precipitation is likely to occur into western NV by Thursday morning, this is expected to be rain due to high snow levels until colder air arrives on Friday. Expect winter driving conditions into lower valleys to be possible through the weekend. 5. Very chilly temperatures look to arrive for New Years weekend with widespread highs at or below freezing. ...Nitty-Gritty Details... By the start of the period Thursday morning, hi-resolution models agree on the initial push of spillover precipitation into Western NV to begin around this time. This is not to say that periodic bouts of rain showers and high elevation snow will not occur in the short-term. It just suggests the strongest mid-level winds (with orthogonal trajectory to the Sierra), moisture push, and forcing out ahead of the upper level trough will result in more favorable spillover set up. Consequently, this is when we expect precipitation rates to get cranking in the Sierra, which is reflected by the start time of the upgrade from Winter Weather Advisory to Winter Storm Warning for Greater Tahoe Area and Northeast CA. -Caveat time... Snow levels do not look super impressive to start with,as southerly warm air advection looks to keep things ranging from 6000ft across NE CA to 6500-7000 across Tahoe Basin to 7500 for the Eastern Sierra. This makes Thursday morning a troublesome forecast as Mono county and the eastern Sierra should see very intense snowfall rates, but snow levels will be right around I-80 pass level and likely just above Lake Tahoe level. Probabilistic snow-level guidance keeps Donner pass right around a 50/50 shot of being all snow (with periodic mixing at times) and just about no chance of snow at lake level (should be rain, with perhaps some mixed precip at times). As the upper level trough approaches the region, colder air will get pushed into the area through the day on Thursday, resulting in a gradual trend downward in snow levels. BY Thursday afternoon, those north of US-50 should see snow levels between 5000-6000ft from north to south. Outside of Sierra ridges, the strongest winds at this time look to be down south across the 395 corridor in Mono county, in addition to northern Washoe. Nothing blockbuster, but it could result in areas of blowing snow and reduced visibility... Snow levels will crash as the cold front approaches the region Thursday night. We should see a full transition to snow for the lower valleys by Friday morning, with nothing really suggesting they will rise above valley floors through the remainder of next week so they will no longer be a major forecast concern... As suggested in previous forecast issuance, the biggest concern for widespread (all of NE California and Western Nevada) travel impacts will start Friday, as model consensus is in rather good agreement of accumulating snowfall in the lower elevations starting this time. It is challenging to pinpoint a clear-cut break in the action at any point through Tuesday, as no ensemble cluster is in good agreement as far as timing goes. In other words, GFS ensemble provides a slight break both Saturday morning and especially Monday afternoon where as European ensemble shows a lull late Friday night and Sunday evening. It`s worth noting that all ensemble clusters have high-end "tails" through these time periods, hence the difficulty in saying with certainty when we will see a break in precipitation. It`s best to prepare for some level of impacts through this entire time period and we should get better ideas in the coming days of when breaks in the action, if any, can be anticipated. Greatest chance for strong to even damaging winds will arrive Sunday, with about a 30-40% chance damaging winds (60mph or greater) across Surprise Valley, 30% along US-395 in Washoe Valley, and a 40% chance along US-395 between Topaz Lake and Bridgeport. It`ll officially be after Christmas, so your decorations may not be able to hangout through New Years... A couple of slider-like systems look to drop into the region from the north next region Monday, Wednesday, and again on Friday. The coldest signals are Wednesday and Friday, however. Each of these will bring an additional shot of snowfall along with reinforcing cold air. If you dislike chilly temperatures now will be the time to take that trip to Florida you`ve been promising your kids. All of us may struggle to get above freezing through all of next weekend. Brr -Dustin && .AVIATION... LLWS and moderate turbulence due to mountain waves for all terminals will persist through Wednesday night. A series of systems that approach the area will bring rounds of heavy mountain snow. Visibilities will be diminished greatly with mountain obscuration likely and periods of LIFR/IFR for KTRK and KTVL the remainder of this morning into Wednesday night. For the valleys and terminals such as KRNO, KCXP, and KMEV, light to moderate precipitation could be in the form of rain/snow transitions at times on Thursday. Flight conditions will include icing issues and wind gusts that will create moderate to severe turbulence and LLWS. Friday, snow levels will drop to valley floors, bringing increased chances of snow to all terminals. -Amanda && .REV Watches/Warnings/Advisories... NV...Winter Weather Advisory until 4 AM PST Thursday NVZ002. Winter Storm Warning from 4 AM Thursday to 4 PM PST Sunday NVZ002. CA...Winter Weather Advisory until 4 AM PST Thursday above 5000 feet in CAZ071. Winter Storm Warning from 4 AM Thursday to 4 PM PST Sunday CAZ071. Winter Storm Warning from 4 PM this afternoon to 4 PM PST Sunday CAZ073. Winter Weather Advisory until 4 AM PST Thursday CAZ072. Winter Storm Warning from 4 AM Thursday to 4 PM PST Sunday CAZ072. && For more information from the National Weather Service visit... http://weather.gov/reno
The Truth Is Stranger Than Fiction!
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