Then there is Hurricane season which will start in June. I think everyone is hoping that the COVID-19 virus will settle down with warmer weather (which for now is only a hope).
See this article, FEMA Tackles COVID-19 While Also Facing Past Disasters, Spring Flood Season, which speaks to some of the staffing challenges that FEMA has had over the years. And, it is not just new disasters you have to worry about. There are likely hundreds of past disasters that remain open with disaster recovery work being done and having to be accounted for by FEMA.
Lastly, there is no "earthquake season." One could happen at any time and we are way over due for a significant shaker somewhere in the United States. I do believe in confluence, a coming together of multiple disasters simultaneously. Bad things can happen in bunches.
Claire Rubin, Recovery Diva shared the link above.