The latest forecasts are very worrying regarding the heavily damaged Oroville Dam in California. And I am surprised there is to so little talk by CA state officials and the media about the danger.
During the past few days, with little rain and active drainage of water, the dam level has been reduced substantially (see image)
But central California and the Sierra Nevada mountains are about to be hit again...quite hard, with a strong atmospheric river (see moisture plot for 1 AM Monday). The red and white colors shows high column integrated water vapor values. Aimed right at the dam.
The forecasts show substantial precipitation with this atmospheric river. Here is the accumulated precipitation for the 24h period ending 4 PM Monday from the excellent NCAR high-resolution ensemble system (the ensemble mean). 4-8 inches over the Sierra.
But that is the ensemble mean or average. But there is a chance it could be more, so here is the ensemble maximum, the ensemble member with the highest amount of precipitation. Much more (30-50% more in some locations)..and a serious problem for Oroville Dam.
The 48h precipitation total ending 4 AM Tuesday from the GFS model projects 5-10 inches in the mountains.
And the European Center model has the same idea, with 5-7 inches
Hydrological forecasts by the National Weather Service, project a rapid rise of the Feather River, the main feed into the reservoir behind the dam, with the flow quadrupling from around 7.5 thousand cubic feet per minute to around 32 thousand.
This is a dangerous situation and, as always, there is uncertainty with our forecasts. Why is there so little discussion of the rapidly increasing precipitation?
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And if you want to read an interesting blog about an unusually strong cold front that hit Hawaii, check this out:
http://ift.tt/2kCaDwc
from Cliff Mass Weather Blog http://ift.tt/2lYqFAC
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