The Summer of COVID-19 is drawing to a close, and many experts fear an even bleaker fall. They suggest that American families should start planning for Thanksgiving by Zoom. Yet there are many uncertainties. Public health scientists say it’s easier to forecast the weather on Thanksgiving Day than to predict how the American coronavirus crisis will play out this autumn. They say school reopenings, holiday travel and more indoor activity because of colder weather could all separately increase transmission of the virus and combine in ways that could multiply the threat.