Wednesday was another day of thick smoke over much of the state with conditions again the worst over eastern Iowa. One metric to assess the smoke is surface visibility reports from the airport weather stations. The Cedar Rapids station reported visibility at or below 2 miles starting Tuesday morning and lasted until Wednesday evening making for a streak lasting just over 37 hours. The featured chart presents IEM computed streaks of the site having a visibility of 2 miles or below for at least 16 hours during the summer months. No other streak is to be found lasting even 24 hours, so this current event is very exceptional. Such streaks are much more common during the cold season when low clouds and fog can persist for long periods of time due to limited heating and mixing of the lower atmosphere.

Voting:
Good = 9
Bad = 0

Tags:   smoke