New Yorkers have been bracing themselves all summer for severe heat, which has yet to arrive.

August isn’t over yet. This week, Mayor de Blasio and other public officials participated in what the City described as a “Summer Emergencies Tabletop Exercise Meeting.” The focus of the emergency planning exercise? A deadly heat wave.

“The notion here is that we’re keenly aware of climate change and what it has meant for this city,” said the Mayor at a press conference after the exercise. “The world has had more than 350 consecutive months of above average temperature. I think we understand fully what could be in store for us in the future, especially – an example locally – 2012, the hottest summer ever in the Northeast.”

The City is also working on ways to literally cool the five boroughs down, and reduce what is described as the “urban heat island” effect. This includes planting hundreds of thousands of trees, re-painting rooftops and greening them with plants.

While the western United States has been coping with wildfires and historic drought, the Northeast has been experiencing an unusually mild summer. Water levels at the city’s upstate drinking water reservoirs are also higher than average at this time of year.

Despite current temperatures, New York City’s long-term future, say its scientists, is a hotter and wetter one. And this poses a real threat to the city’s most vulnerable populations.

“We’ve seen the domino effect that can occur in a heat emergency,” Mayor de Blasio said. “What it means for peoples’ health, what it means particularly for our elderly and disabled citizens. So we went through a variety of situations and determined the kind of response that we could make.”

In addition to the Mayor, Office of Emergency Management Commissioner Joe Esposito, Health Commissioner Mary Bassett, First Deputy Mayor Tony Shorris, Deputy Mayors Alicia Glen and Lilliam Barrios-Paoli, and representatives from the State and the MTA, participated in the exercise.

De Blasio said that city officials created a hypothetical situation in which they were coping with a mounting crisis. Joe Esposito led the exercise. “A series of events were occurring, the crisis continued to deepen, and all the pertinent agencies around the room…had to respond in real time and make decisions to be able to handle the challenges that kept coming up,” the Mayor described.

“I’ve been through dozens of them [emergency drills],” said Commissioner Esposito, “and you’re on the edge of your chair…The mayor brought up a couple of points that we didn’t prepare for – medication distribution, some food distribution, some of these scenarios – and we said, ‘Gee, we don’t have an answer to that question.’ So we’ll get an answer to the question as a result of the drill.”

The Mayor noted that Health Commissioner Bassett had been tasked to come up with a plan for distributing medication to homebound New Yorkers in the event of an emergency, and “have it ready immediately”.

“We did a lot of comparison in there about what happened after Sandy,” said the Mayor. “Even though that was a very different kind of emergency, there were some things that did not work properly after Sandy. We talked about…some of the adjustments we want to make, some of the gaps that we need to fill.”

In recent weeks, the City said it also conducted a similar exercise predicated upon the threat of a coastal storm or hurricane, and another, related to the introduction of a biological agent.