Heat Wave

The Covid-19 lockdown had the odd effect of making the entire spring season disappear. Spending three months largely indoors, with a reduced project workload but a huge increase in administrative work, erased any sense of the tail end of cold weather and the start of warm weather. The lockdown has mostly ended in time for summer, which is honestly not when New York is at its best. Over fifty years ago, John Steinbeck wrote that “New York is an ugly city, a dirty city. Its climate is a scandal, its politics are used to frighten children, its traffic is madness, its competition is murderous.” I’m going to focus on only the third of his complaints.

The usual definition of a heat wave in NYC, and generally in the northeastern US, is three consecutive days of high temperatures over 90F. That may not seem so hot to people from the western part of the country, but our summers tend toward a humid heat that is really oppressive, and the urban heat island effect is terrible in much of the city, made worse by the huge masses of brick that absorbs heat during the day and then warms the night. We passed 90F on Sunday and are forecast to have highs up there until Thursday, so this meets the minimum criterion. But it also goes way beyond that bar: after a forecast high of only 88F on Thursday, we’re supposed to be well over 90F through next Tuesday. The humidity has varied between 40 and 60% or so every day; the low temperatures have been 77 to 81F. The condition of 77F and 60% humidity is awful in itself, and that’s the low in the middle of the night.

The general pattern of our heat waves is a few days (in this case, over a week) of heat and humidity, which breaks spectacularly, with thunderstorms and downpours, when a cold front comes in from the northwest. Sometimes, as is happening today, a weak front comes through and rather than breaking the heat, just dumps a whole lot of water to turn the entire city into a sauna. This pattern, of increasing heat, a big storm, a few nice days, and then a repeat of the cycle, is ingrained in us.

The amount of rain that falls here in general is not really understood. July and August are our rainiest and third-rainiest months (May is second), but our annual average is over 46 inches. To put that in perspective of two cities with a reputation for rain, London gets about 23 inches per year and Seattle gets about 37 inches. New York averages around 120 days with rain versus 110 for London and 150 for Seattle. In other words, we have downpours they do not. We also have a lot of bright sunny days, which is great in the winter but currently not so great.

Yes, I’m complaining. It’s hard to think deep thoughts about engineering, or anything else, when your back is stuck to a chair.