Thanks!

I might try turning this into a full-blown tutorial for the pages, but in case that never gets started, here's the code I've copy-pasted together:

var temperature;
var humidity;

var dht = require("DHT22").connect(D2);

function onPage(req, res){
  var page = temperature + "," + humidity;
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.end(page);
}

function writeScreen(){
  g.clear();
 g.drawString(temperature, 0, 0); 
  g.drawString(humidity, 0, 30);
 g.flip();
}
// I2C
I2C1.setup({scl:D5,sda:D4});
var g = require("SSD1306").connect(I2C1, writeScreen);
g.setFont("4x6", 5);

function readDHT(){
  dht.read(function(a) {
   temperature = a.temp.toString();
    humidity = a.rh.toString();
    console.log("Temp is "+a.temp.toString()+" and RH is "+a.rh.toString());
  });
  writeScreen();
}


setInterval(readDHT, 2000);

require("http").createServer(onPage).listen(80);

My node.red asks http://esp_hostname.local for the page, and parses it as csv.