As nearly nine trillion tons of water fell on the Houston area in the wake of Hurricane Harvey last week, emergency managers and officials at all levels of government scrambled to respond quickly and effectively. The flooding is still wreaking havoc in Texas, but another storm, Hurricane Irma, is set to make landfall in Florida, and there are already lessons to be learned from Harvey's fallout.

Climate change continues to make weather more severe and severe weather more frequent, and other areas facing natural disasters, from wildfires in Washington state to cyclones in Australia, need to speed up their learning curve. This is especially true on the communications front, as media scrutiny intensifies in a crisis and critics with their own motivations eagerly grab the nearest microphone.

Entrepreneurs, in turn, would be wise to pay attention.

Stick to your (local) guns.

Perhaps the most controversial aspect of the Harvey response so far (aside from Melania Trump's stilettos) has been Houston Mayor Silvester Turner's decision not to order a mandatory evacuation. Facing blowback, some of it partisan, from the Texas governor and from various media outlets, he could have caved in to the pressure.

Instead, he drew on the lessons from the failed evacuation for Hurricane Rita in 2006, when more than 100 people died. The value of this local knowledge, communicated effectively, quickly became apparent.

Mayor Turner and Harris County Judge Ed Emmett, a Republican, turned quickly to Twitter to double down on the original decision to not mandate evacuation, and followed it up with a clear, no-bones news conference urging residents to stay in their homes. This direct and side-by-side communication delivered the message clearly, validated it across partisan lines, and very possibly saved lives.

Stay social in an emergency.

Communications infrastructure is always problematic in the wake of a natural disaster, as cell towers and 911 centers are knocked out and phone lines are tied up with thousands of calls. But even a thin internet connection can make social tools accessible. Social media provides a powerful alternative when those affected by disasters need it most and, in Houston, has been a dominant force for connecting stranded residents with support.

According to NPR:

"These social media platforms have become de facto meeting points for thousands of stranded people as they reach out to their neighborhood groups and the outside universe for help. ... It's not just stranded residents who are turning to sites like Nextdoor. The Houston Office of Emergency Management and the Harris County Sheriff's Office are using the site to post emergency information and communicate directly with residents."

While government entities like these aren't usually known for their social media savvy, acting to take advantage of high-traffic platforms allowed them to communicate with survivors and to direct first responders their way. Hurricane Katrina became as well known for its disastrous response as for its initial damage, which was compounded by communications stumbles.

At the time, social media was unavailable as a mass communications tool; it could have been helpful to fill the gaps left by the telecom infrastructure collapse in and around New Orleans.

Public officials shouldn't be shy about communicating on Twitter, Facebook, Instagram, and Nextdoor in a crisis -- it's the best way to reach the folks who need information the most, and in a timely fashion. Business schools teach companies to "go where the people are." In a crisis that demands broad dissemination of an official response, this is often truer than ever.

The emergency response to Harvey will be judged over years, not days, and punditry has a short shelf life. But effective responses can mitigate crisis and provide lifesaving help at critical times, and can carry lessons for leaders in the business community as well. Speak clearly, let your on-the-ground knowledge trump outside pressure, and disseminate your message widely (when appropriate).

For leaders in Florida and across the Caribbean, it's crucial to get it right. And fast.