Here's what's here in northern California via the Berkeley Nuclear Physics Lab Air and Water Sampling. In my opinion, do not drink or consume dairy products (cow milk, cheese) from dairies on the West Coast.

Milk:

1-131 IS THE ONLY 0.70 (NORMAL IS 0.14, clear sign of contamination) BUT.. You would have to consume 3800 liters of contaminated milk to be equivalent to one round trip California to New York.  So, still safe... Take your seaweed or micro Iodine dose per day (not more than 5 mg at this point). 

Air:

Based on milliSieverts (mS), a trip to New York from California exposes you to 0.5 mS.  Currently (Apr. 3) you need 6.1 trips to equal the I-131 contained today the air. The Cesiums are below baseline at this time (minimal, background).

Water: 

Tap: all below minimum or baseline values.

Rainwater:  I-131 elevated. You would need to drink 1700 liters to equal one trip California to New York. This is however 15x the normal baseline.  Cesium 137 is 6x normal value and would require drinking 4800 liters to equal a trip across country.

IN SUMMARY

I-131 in rainwater is higher than baseline significantly but in a 'safe' zone at this time, even according to the most liberal estimates. 

  Its time to further protect yourself: My Radiation protection article is most informative...

- Dr. Daniel Beilin