User story: As a water resources manager, I want to have quick access to maps showing the status of water availability in my state compared to previous years.

This feature will enable downstream users to create national-scale maps.

1. Pull NWIS data of current streamflow
2. Calculate historical percentile values for all sites with current conditions for the day of the year on daily, 7-day, 14-day, 28-day average timescales
3. Create a standardized data output to enable downstream mapping of data and percentile values at the site, state and HUC2 scales

Calculations:

• Average streamflow on daily, 7-day, 14-day, 28-day timescales
• Percentile classes and ranking

Considerations:

• need to handle negative flows

Nice to have:

• filtering dataset to the HCDN network, as per Xiaodong Jian recommendation