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UPDATE ON WEEKEND STORM SYSTEM IN SOUTHERN CALIFORNIA

I'm about a week late in posting this, but I've been insanely busy at the brewery training for my new position.

Showers should arrive early tomorrow morning, then we will see periods of moderate to heavy rain in the afternoon and evening. The chance for rain will persist into Sunday, but showers will be more widely scattered as the trough axis (storm's core) shifts east. An isolated shower could linger into Monday, but most of the rain will be gone.

Rain totals will be impressive with this system. Most of San Diego County could see 1 to 2" with higher amounts in the mountains.


Snow levels will start at 5000 to 7000 feet early Saturday. They will then drop to 4000 to 5000 feet Saturday night. Snow levels could dip as low as 3000 to 4000 feet on Sunday. Accumulations will be impressive with this system. Big Bear down to Mount Laguna could see around 6 to 12" of new snow!


This is going to be a massive snow storm for the Central Sierra. Check out these snow totals!


MONDAY SNOW IN VIRGINIA

Latest data shows an impressive shift northward with the track of this storm. As I said before, you have to be careful with these type of systems. They can sneak up on you! I'm going to include the Richmond metro in the 1 to 3" category and put Emporia in the 1" or less category.

I've posted the computer forecasts below. Good luck tomorrow!




COMMENTS ON MONDAY SNOW IN VIRGINIA

You always have to be wary of a clipper system that is strengthening as it heads your way. I've been burned many times by these type of storms because they usually bring more snow than expected. Although surface temperatures will be above freezing, they will quickly drop once the precip starts. The air is very dry, so there will be major evaporative cooling.

I think the NAM does a pretty good job with this event. It won't be a 10:1 snow-to-liquid ratio, so the map below is overdone:


The next map uses the Kuchera algorithm and seems more plausible. Richmond should see 1" or less, though an area from Petersburg to Emporia could see 1 to 3".


VERIFICATION - WINTER OUTLOOK

Meteorological spring starts today, so it is time to verify my winter outlook. Obviously snow can still occur across most of the U.S. during this time of the year, but my forecast was for December through February. Last November, I typed up this summary:
San Diego - Last winter was cooler and wetter than average. This December-February should have below average temperatures and slightly above average precipitation. The southern stream will be weak, so we might not see any major rain events (exceeding 2"). Instead, I expect occasional moderate events through the winter. This could eat away at snow totals in the mountains, but colder air in the upper atmosphere could compensate a little.
Richmond - Last winter was cooler than average (cool Dec-Jan, warm in Feb) and drier than average (Dec was wet, Jan-Feb dry). Snow last year was *just* below average with a total of 10.7". I expect December-February temperatures to stay slightly above average and precipitation to hover near or slightly below average. There should be two to three cold blasts, though I don't think there will be any prolonged cold weather (over two weeks). After watching the storm track over the past couple months, I wouldn't be surprised if there will be a couple threats for a significant snow storm. Regardless, snow totals should stay near or below average at roughly 6 to 12".
Here were my forecast maps:





Here is what actually happened:







Although I'm generally happy with my temperature forecast in San Diego and California, I had a significant miss on the precip outlook. In retrospect, I should have known better considering the lack of a strong southern stream.

I'm very happy about my Richmond outlook (I've had more practice with Mid-Atlantic weather). 

I had a major bust with temperatures in the Northern Plains and New England. The handwriting was on the wall, in fact, I even talked about it during my discussion on the Arctic Oscillation and NAO. 

Lastly, I wish I would have extended my heavy precip area down into Texas. I drew my precip outlook two or three times. Each time I seriously considered putting Texas into the "above average" category. Instead, I stuck with persistence. Anyway, I'm glad I was wrong...Texas needed that moisture!

FORECAST

HOURLY TEMPERATURE FORECAST

COAST INLAND