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The second reason for the lack of data is that nine of these years, the 5000 cfs mark was either not made or was not exceeded for a sufficient period of time to qualify as making the 5000 cfs mark (i.e. the daily average hit 5000 cfs for one day then retreated). A slightly different look at this variable showed little additional information in that the date of ‘peak’ flow (highest average daily cfs) was poorly correlated with most HCI variables. The one slight exception to this was the NAO in a very latent mode (March to May) average or as the spring is proceeding along. The only item to note is th that the date of ‘peak’ flow is typically at or earlier than the average date (June 8) on all but one of the years that the NAO is greater than 0.25 with half of those years having a st peak flow within a day or two of June 1. However, this is only useful knowledge if a skillful forecast of the NAO is available for that year. Summary: Although ENSO’s well noted impacts have been oft discussed and researched it becomes apparent that influences of measured tangible variables in the Atlantic have a definitive non-random influence in some of the State of Colorado’s river basins. Some preliminary research has been performed on the connection between ENSO and the AMO on larger time scales and longer periods of stream flow. The work performed in this study confirms this notion on one and two-year time scales. Given the longer-time scales of indices like the AMO and PDO the results will hopefully enlighten the reader into the apparent longer time scales of large oscillations and their long-term impacts. In a decade where the multi-year stream flow values have generally been lacking behind the long-term averages (1999-2007) preceded by seemingly many bountiful years in the 1990’s one must wonder if these variables are the source of our stream flow variability. The cause and effect of say the AMO, on precipitation and subsequent stream flow has yet to be definitively quantified. However, one may speculate on factors such as altered preferred storm tracks through the Western US as systems move in from the Pacific Ocean or is there a change in the moisture (water vapor) content in the atmosphere that alters the amount of moisture to precipitate out of the clouds? Regardless of the mechanisms at work in the variability of the hydrologic cycle, the recent light shed on some Colorado’s basins and their importance on the future of Colorado’s surface water both intra and inter-state might be pursued at further length. Just a decade or so ago, the scientific community was beginning to get their hands around the ENSO phenomenon. Will research on other HCI variables be as important? Some of the data in this report suggests that might be possible in the near future. 41