There has been plenty of snow already in the convergence zone.....here is a recent radar image, See the band with green in the middle...that is the convergence zone.
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Some locations have gotten 1-2 inches already. Take a look at recent cam in Everett:
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And here is a snow video taken in Lake Stevens this morning:
I have taken a look at the latest model runs this morning and they are amazingly consistent both in time and among the models. Although this give me confidence in their forecast, there is still uncertainty in exact positions of features and snow accumulations.
Here is the 24-h snowfall ending 4 AM on Thursday:
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And on Thursday, eastern Washington will get crushed by very strong northerly winds and extraordinarily cold temperatures (single digits and below zero).
So bottom line for snow. My prediction: South Seatttle--1-3 inches, North Seattle--2-5 inches, northern Snohomish (3-8 inches).
Good news for commuters and SDOT tomorrow: temperatures will remain above freezing, SO NO SOLID ICE LAYER like Nov 22, 2010.
I am planning to try another NOWCASTING experiment tomorrow (Wednesday). Frequent updates throughout the day on what is happening and will happen during the next few hours.
Finally, I would like to thank those that have contributed to the development of our local forecasting capability (upper right of this blog for more info)... I have already used some of the funds to replace some aging hardware.
PS: I am looking for video of Jim Forman if anyone has it or recording him tonight!