UPDATE: At 2:30 PM New York time we are seeing some of the lowest levels of tweeting coming from New York we have ever seen. Normally we would never see levels of Honolulu or Philadelphia equal to New York city, this must be from the evacuation of parts of the city.
We have seen some dramatic weather today, firstly a small Tsunami has heat Hawaii. We rarely see in major tweeting in the large island of Hawaii with its relatively small population, but we are seeing high tweeting in Honolulu, indicating people may be a bit shaken up but infrastructures seems to be working well.
Current tweeting level for Honolulu Hawaii
The center of New York, normally a major twitter producer at any time but we anticipate will drop as transport closes.
New York, above, and Philadelphia are in the path of Hurricane Sandy expect to make ground this evening. From our experience by past natural disasters we would anticipate the level of tweeting to rise dramatically just before the storm hits. This will come down but how much is a function of the severity of the weather. If the weather is not so bad it will tapper down either as systems are overloaded or people get tired tweeting minute by minute updates. A dramatic drop in tweeting will be a clear indication of a major disaster has happened.
Currnt geo-tagged tweeting coming form Philadelphia, not very high.
The largest natural disaster we have been able to study so far was the Japan Tsunami. What we saw in that case was areas outside of the impacted area having extremely high tweeting with large coastal areas producing no geo-tagged tweets, we hope to not see anything like this today.