** The “Pineapple Express” set to arrive late Wednesday into Thursday, with additional storms to last through the weekend! **
48°F – Outlook and Forecast – Weak high pressure over Nor Cal kept the storm track to our north today. Despite that, overrunning clouds persisted all day over Nor Cal and the foothills.
Big changes are coming however beginning Wednesday as the jet stream will dive south, ushering a strong storm, an AR event (aka “Pineapple Express”) with abundant moisture, reaching the coast early Wednesday morning (see graphic). Heavier precipitation will spread into the foothills and Sierra later in the day and night, bringing increasing foothill rain and Sierra snow. Rain/snow will become heavy at times, with strong winds, to 40+ mph in the foothills, with 50-60 mph winds possible over the Sierra passes and 80-100 mph winds over the ridgetops. 3+ ft snow is possible over the Sierra ridgetops, 1-2 feet of snow over the summits and up to 1 foot in the Lake Tahoe, Truckee areas. Rainfall amounts in the foothills could total 2.5 to over 3 inches by Friday night. More rain and snow is on tap for the weekend as well.
This will be the strongest storm we’ve seen this year so far. We actually haven’t seen a storm this strong since Feb of 2014, so, some of us newcomers may not be accustomed to a storm such as this. Be prepared for strong winds, heavy rain, with localized street flooding possible.. Colder air behind the storm may drop snow levels into the upper foothills (3500-4000 ft) early Friday morning.
Additional storms are forecast to impact the area Saturday into Sunday. These storms will be colder with snow levels once again dropping into the upper foothills. More details on the weekend forecast in the next couple of days.
What to expect: Expect mostly cloudy skies tonight in the foothills with a slight chance of showers moving in Wednesday morning. Rain increasing, becoming heavy at times by late afternoon, lasting into the overnight hours. Strong winds 25-40+ mph may cause downed branches and trees with the risk for isolated power outages. Heavy rain may also cause localized flooding in low lying areas around the foothills.
Snow levels in the Sierra will start around 8000 ft early Wednesday, lowering to 7000 ft Wednesday night, 6000 ft Thursday morning, lowering further to around 3500-4000 ft Thurs night into Friday. Another, colder storm is on tap for Saturday night and Sunday with snow levels dropping to as low as 3000-3500 ft Sunday night.
Winter Storm warnings are up for the Sierra late Wednesday night, lasting through Thursday night for very heavy snow and wind. Poor driving conditions over the Sierra are likely Wednesday night, lasting into the weekend. Chain controls are likely and road closures are possible, so travel into the Sierra from late Wednesday on is not recommended. It would be wise to postpone your trip if at all possible.
It looks like we’ll get a little break from the storminess early next week, but another cold storm may be looming on the horizon by later next week. More on that later.
Stay tuned to the latest developments and local weather and road conditions right here at Cascade Shores Weather. Enjoy your evening!