Just FYI, since forecast.io is becoming darksky.net, I've changed forecast.alfredworkflow accordingly to dark-sky.alfredworkflow:
https://github.com/kejadlen/dark-sky.alfredworkflow
https://github.com/kejadlen/dark-sky.alfredworkflow/releases/tag/v2.0.0
The only change needed (assuming I didn't screw up the transition) is moving from FORECAST_API_KEY to DARK_SKY_API_KEY after updating the workflow.