diff --git a/air-gradient-open-air.yaml b/air-gradient-open-air.yaml
index 9aab8c0..79844ec 100644
--- a/air-gradient-open-air.yaml
+++ b/air-gradient-open-air.yaml
@@ -1,15 +1,40 @@
 # Airgradient Open Air Outdoor v1.1 presoldered
 #
-# @llamagecko, @Hendrik and @spectrumjade from AirGradient forum
+# @llamagecko, @Hendrik, @spectrumjade, and @ex-nerd from AirGradient forum
 # did most of the work for this integration, see the following thread:
 # https://forum.airgradient.com/t/outdoor-monitor-esphome-configuration/823
 #
+# Upstream AirGradient Firmware can be found here:
+# https://github.com/airgradienthq/arduino/blob/master/examples/DIY_OUTDOOR_C3/DIY_OUTDOOR_C3.ino
+#
 
 substitutions:
   id: "1"
   devicename: "airgradient-open-air"
   # WARNING: upper_devicename is component of SSID which is limited to 32 characters
   upper_devicename: "AirGradient Open Air"
+  # Only trigger the particle sensor every 3 minutes so it can go into sleep mode and extend its operational lifetime.
+  # Here as a substitution mostly to ensure consistent use in this file (several calculations rely on this 3min value).
+  pm_update_interval: "3min"
+
+globals:
+  - id: aqi_delay_mins
+    type: int
+    restore_value: no
+    # AQI is calculated over a 24 hour minimum, but EPA says it's acceptable to
+    # report at 75%, or 18 hours: https://forum.airnowtech.org/t/aqi-calculations-overview-ozone-pm2-5-and-pm10/168
+    initial_value: '1080'
+  - id: nowcast_delay_mins
+    type: int
+    restore_value: no
+    # NowCast is calculated over a 12 hour period
+    initial_value: '720'
+  - id: pm_2_5_hourly_avg
+    type: std::vector<float>
+    restore_value: no
+  - id: pm_10_0_hourly_avg
+    type: std::vector<float>
+    restore_value: no
 
 esphome:
   name: "${devicename}-${id}"
@@ -20,7 +45,7 @@ esphome:
   platform: esp32
   board: esp32-c3-devkitm-1
 
-# Enable logging
+# Enable logging?
 logger:
   baud_rate: 0
 
@@ -35,8 +60,8 @@ ota:
 
 wifi:
   networks:
-  - ssid: !secret wifi_ssid
-    password: !secret wifi_password
+    - ssid: !secret wifi_ssid
+      password: !secret wifi_password
   reboot_timeout: 15min
 
   # Enable fallback hotspot (captive portal) in case wifi connection fails
@@ -44,20 +69,21 @@ wifi:
     ssid: "${upper_devicename} Hotspot"
     password: !secret fallback_ssid_password
 
+# The captive portal is a fallback mechanism for when connecting to the configured WiFi fails.
+# https://esphome.io/components/captive_portal.html
+captive_portal:
+
 # Used to support POST request to send data to AirGradient
 # https://esphome.io/components/http_request.html
 http_request:
 
 # Creates a simple web server on the node that can be accessed through any browser
 # https://esphome.io/components/web_server.html
+# Turn on the webserver so we can connect and look at raw stats
 web_server:
   port: 80
   include_internal: true
 
-# The captive portal is a fallback mechanism for when connecting to the configured WiFi fails.
-# https://esphome.io/components/captive_portal.html
-captive_portal:
-
 # Create a switch for safe_mode in order to flash the device
 # Solution from this thread:
 # https://community.home-assistant.io/t/esphome-flashing-over-wifi-does-not-work/357352/1
@@ -68,36 +94,313 @@ switch:
 
 button:
   - platform: restart
+    id: button_restart
     name: "Restart"
     disabled_by_default: true
-    id: button_restart
 
 output:
   - platform: gpio
     id: watchdog
     pin: GPIO2
 
-# Reset hardware watchdog every 5 minutes
+script:
+  - id: calculate_aqi
+    mode: restart # restart script if called while it's still running (because we run it after pm2.5 and pm10 sensors)
+    then:
+      - lambda: |
+          // AQI is calculated over a 24 hour minimum, but EPA says it's acceptable to
+          // report at 75%, or 18 hours: https://forum.airnowtech.org/t/aqi-calculations-overview-ozone-pm2-5-and-pm10/168
+          int hours_to_wait = 18;
+
+          // https://en.wikipedia.org/wiki/Air_quality_index#Computing_the_AQI
+          int aqi_2_5 = -1;
+          int size_2_5 = id(pm_2_5_hourly_avg).size();
+
+          if (size_2_5 >= hours_to_wait) {
+
+            float sum = 0.0;
+            for (int i = 0; i < size_2_5; i++) {
+              sum += id(pm_2_5_hourly_avg)[i];
+            }
+
+            float pm25 = sum / (float)size_2_5;
+            if (pm25 < 12.0) {
+              aqi_2_5 = (50.0 - 0.0) / (12.0 - 0.0) * (pm25 - 0.0) + 0.0;
+            } else if (pm25 < 35.4) {
+              aqi_2_5 = (100.0 - 51.0) / (35.4 - 12.1) * (pm25 - 12.1) + 51.0;
+            } else if (pm25 < 55.4) {
+              aqi_2_5 = (150.0 - 101.0) / (55.4 - 35.5) * (pm25 - 35.5) + 101.0;
+            } else if (pm25 < 150.4) {
+              aqi_2_5 = (200.0 - 151.0) / (150.4 - 55.5) * (pm25 - 55.5) + 151.0;
+            } else if (pm25 < 250.4) {
+              aqi_2_5 = (300.0 - 201.0) / (250.4 - 150.5) * (pm25 - 150.5) + 201.0;
+            } else if (pm25 < 350.4) {
+              aqi_2_5 = (400.0 - 301.0) / (350.4 - 250.5) * (pm25 - 250.5) + 301.0;
+            } else if (pm25 < 500.4) {
+              aqi_2_5 = (500.0 - 401.0) / (500.4 - 350.5) * (pm25 - 350.5) + 401.0;
+            } else {
+              aqi_2_5 = 500; // everything higher is just counted as 500
+            }
+          } else {
+            ESP_LOGD("custom", "Skipping pm2.5 AQI calculation. %d hours remaining.", hours_to_wait - size_2_5);
+          }
+
+          int aqi_10_0 = -1;
+          int size_10_0 = id(pm_10_0_hourly_avg).size();
+          if (size_10_0 >= hours_to_wait) {
+
+            float sum = 0.0;
+            for (int i = 0; i < size_10_0; i++) {
+              sum += id(pm_10_0_hourly_avg)[i];
+            }
+
+            float pm10 = sum / (float)size_10_0;
+            if (pm10 < 54.0) {
+              aqi_10_0 = (50.0 - 0.0) / (54.0 - 0.0) * (pm10 - 0.0) + 0.0;
+            } else if (pm10 < 154.0) {
+              aqi_10_0 = (100.0 - 51.0) / (154.0 - 55.0) * (pm10 - 55.0) + 51.0;
+            } else if (pm10 < 254.0) {
+              aqi_10_0 = (150.0 - 101.0) / (254.0 - 155.0) * (pm10 - 155.0) + 101.0;
+            } else if (pm10 < 354.0) {
+              aqi_10_0 = (200.0 - 151.0) / (354.0 - 255.0) * (pm10 - 255.0) + 151.0;
+            } else if (pm10 < 424.0) {
+              aqi_10_0 = (300.0 - 201.0) / (424.0 - 355.0) * (pm10 - 355.0) + 201.0;
+            } else if (pm10 < 504.0) {
+              aqi_10_0 = (400.0 - 301.0) / (504.0 - 425.0) * (pm10 - 425.0) + 301.0;
+            } else if (pm10 < 604) {
+              aqi_10_0 = (500.0 - 401.0) / (604.0 - 505.0) * (pm10 - 505.0) + 401.0;
+            } else {
+              aqi_10_0 = 500; // everything higher is just counted as 500
+            }
+          } else {
+            ESP_LOGD("custom", "Skipping pm10 AQI calculation. %d hours remaining.", hours_to_wait - size_10_0);
+          }
+
+          int aqi_calc = std::max(aqi_2_5, aqi_10_0);
+          if (aqi_calc > 0) {
+            id(aqi).publish_state(aqi_calc);
+            // Just in case we're counting down, make sure we set to zero
+            id(aqi_delay_mins) = 0;
+            if (id(aqi_delay_mins) > 0) {
+              id(aqi_delay_mins) = 0;
+              id(aqi_mins_remaining).publish_state(0);
+            }
+            // And now publish the category string
+            if (aqi_calc <= 50.0) {
+              id(aqi_category).publish_state("Good");
+            } else if (aqi_calc <= 100.0) {
+              id(aqi_category).publish_state("Moderate");
+            } else if (aqi_calc <= 150.0) {
+              id(aqi_category).publish_state("Unhealthy for Sensitive Groups");
+            } else if (aqi_calc <= 200.0) {
+              id(aqi_category).publish_state("Unhealthy");
+            } else if (aqi_calc <= 300.0) {
+              id(aqi_category).publish_state("Very Unhealthy");
+            } else if (aqi_calc <= 400.0) {
+              id(aqi_category).publish_state("Hazardous");
+            } else if (aqi_calc <= 500.0) {
+              id(aqi_category).publish_state("Hazardous"); // again
+            } else {
+              id(aqi_category).publish_state("Hazardous"); // and again
+            }
+          } else {
+            int remaining_hours = hours_to_wait - std::max(size_2_5, size_10_0);
+            ESP_LOGD("custom", "No AQI calculations available. %d hours remaining.", remaining_hours);
+            // Intervals don't quite overlap with the sensor notification windows,
+            // so let's readjust this just in case it's fallen out of sync.
+            id(aqi_delay_mins) = 60 * remaining_hours;
+            id(aqi_mins_remaining).publish_state(60 * remaining_hours);
+          }
+
+  - id: calculate_nowcast
+    mode: restart # restart script if called while it's still running
+    then:
+      # https://forum.airnowtech.org/t/the-nowcast-for-pm2-5-and-pm10/172
+      - lambda: |
+          // NowCast is always calculated over 12 hours, but this is extracted here
+          // to make debugging easier.
+          int hours_to_wait = 12;
+
+          int nowcast_2_5 = -1;
+          int size_2_5 = id(pm_2_5_hourly_avg).size();
+          if (size_2_5 > 12) {
+            size_2_5 = 12;
+          }
+          if (size_2_5 >= hours_to_wait) {
+          // if (size_2_5 >= 12) {
+            // Calculate min and max
+            float max = 0.0;
+            float min = 31337.0; // just a random large number
+            for (int i = 0; i < size_2_5; i++) {
+              float pm = id(pm_2_5_hourly_avg)[i];
+              if (pm < min) {
+                min = pm;
+              }
+              if (pm > max) {
+                max = pm;
+              }
+            }
+            // Calculate the weight factor
+            float range = max - min;
+            float rate = range / max;
+            float weight_factor = 1.0 - range;
+            if (weight_factor < 0.5) {
+              weight_factor = 0.5;
+            } else if (weight_factor > 1.0) {
+              weight_factor = 1.0;
+            }
+
+            float pm_sum = 0.0;
+            float weight_sum = 0.0;
+            for (int i = 0; i < size_2_5; i++) {
+              float weight_pow = pow(weight_factor, i);
+              pm_sum += id(pm_2_5_hourly_avg)[i] * weight_pow;
+              weight_sum += weight_pow;
+            }
+            float pm25 = pm_sum / weight_sum;
+
+            // https://en.wikipedia.org/wiki/Air_quality_index#Computing_the_AQI
+            if (pm25 < 12.0) {
+              nowcast_2_5 = (50.0 - 0.0) / (12.0 - 0.0) * (pm25 - 0.0) + 0.0;
+            } else if (pm25 < 35.4) {
+              nowcast_2_5 = (100.0 - 51.0) / (35.4 - 12.1) * (pm25 - 12.1) + 51.0;
+            } else if (pm25 < 55.4) {
+              nowcast_2_5 = (150.0 - 101.0) / (55.4 - 35.5) * (pm25 - 35.5) + 101.0;
+            } else if (pm25 < 150.4) {
+              nowcast_2_5 = (200.0 - 151.0) / (150.4 - 55.5) * (pm25 - 55.5) + 151.0;
+            } else if (pm25 < 250.4) {
+              nowcast_2_5 = (300.0 - 201.0) / (250.4 - 150.5) * (pm25 - 150.5) + 201.0;
+            } else if (pm25 < 350.4) {
+              nowcast_2_5 = (400.0 - 301.0) / (350.4 - 250.5) * (pm25 - 250.5) + 301.0;
+            } else if (pm25 < 500.4) {
+              nowcast_2_5 = (500.0 - 401.0) / (500.4 - 350.5) * (pm25 - 350.5) + 401.0;
+            } else {
+              // everything higher is just counted as 500
+              nowcast_2_5 = 500;
+            }
+          } else {
+            ESP_LOGD("custom", "Skipping pm2.5 NowCast calculation. %d hours remaining.", hours_to_wait - size_2_5);
+          }
+
+          int nowcast_10_0 = -1;
+          int size_10_0 = id(pm_10_0_hourly_avg).size();
+          if (size_10_0 > 12) {
+            size_10_0 = 12;
+          }
+          if (size_10_0 >= hours_to_wait) {
+          // if (size_10_0 >= 12) {
+            // Calculate min and max
+            float max = 0.0;
+            float min = 31337.0; // just a random large number
+            for (int i = 0; i < size_10_0; i++) {
+              float pm = id(pm_10_0_hourly_avg)[i];
+              if (pm < min) {
+                min = pm;
+              }
+              if (pm > max) {
+                max = pm;
+              }
+            }
+            // Calculate the weight factor
+            float range = max - min;
+            float rate = range / max;
+            float weight_factor = 1.0 - range;
+            if (weight_factor < 0.5) {
+              weight_factor = 0.5;
+            } else if (weight_factor > 1.0) {
+              weight_factor = 1.0;
+            }
+
+            float pm_sum = 0.0;
+            float weight_sum = 0.0;
+            for (int i = 0; i < size_10_0; i++) {
+              float weight_pow = pow(weight_factor, i);
+              pm_sum += id(pm_10_0_hourly_avg)[i] * weight_pow;
+              weight_sum += weight_pow;
+            }
+            float pm10 = pm_sum / weight_sum;
+
+            // https://en.wikipedia.org/wiki/Air_quality_index#Computing_the_AQI
+            if (pm10 < 54.0) {
+              nowcast_10_0 = (50.0 - 0.0) / (54.0 - 0.0) * (pm10 - 0.0) + 0.0;
+            } else if (pm10 < 154.0) {
+              nowcast_10_0 = (100.0 - 51.0) / (154.0 - 55.0) * (pm10 - 55.0) + 51.0;
+            } else if (pm10 < 254.0) {
+              nowcast_10_0 = (150.0 - 101.0) / (254.0 - 155.0) * (pm10 - 155.0) + 101.0;
+            } else if (pm10 < 354.0) {
+              nowcast_10_0 = (200.0 - 151.0) / (354.0 - 255.0) * (pm10 - 255.0) + 151.0;
+            } else if (pm10 < 424.0) {
+              nowcast_10_0 = (300.0 - 201.0) / (424.0 - 355.0) * (pm10 - 355.0) + 201.0;
+            } else if (pm10 < 504.0) {
+              nowcast_10_0 = (400.0 - 301.0) / (504.0 - 425.0) * (pm10 - 425.0) + 301.0;
+            } else if (pm10 < 604) {
+              nowcast_10_0 = (500.0 - 401.0) / (604.0 - 505.0) * (pm10 - 505.0) + 401.0;
+            } else {
+              // everything higher is just counted as 500
+              nowcast_10_0 = 500.0;
+            }
+
+          } else {
+            ESP_LOGD("custom", "Skipping pm10 NowCast calculation. %d hours remaining.", hours_to_wait - size_10_0);
+          }
+
+          int nowcast_calc = std::max(nowcast_2_5, nowcast_10_0);
+          if (nowcast_calc > 0) {
+            id(nowcast).publish_state(nowcast_calc);
+            // Just in case we're counting down, make sure we set to zero
+            if (id(nowcast_delay_mins) > 0) {
+              id(nowcast_delay_mins) = 0;
+              id(nowcast_mins_remaining).publish_state(0);
+            }
+            // And now publish the category string
+            if (nowcast_calc <= 50.0) {
+              id(nowcast_category).publish_state("Good");
+            } else if (nowcast_calc <= 100.0) {
+              id(nowcast_category).publish_state("Moderate");
+            } else if (nowcast_calc <= 150.0) {
+              id(nowcast_category).publish_state("Unhealthy for Sensitive Groups");
+            } else if (nowcast_calc <= 200.0) {
+              id(nowcast_category).publish_state("Unhealthy");
+            } else if (nowcast_calc <= 300.0) {
+              id(nowcast_category).publish_state("Very Unhealthy");
+            } else if (nowcast_calc <= 400.0) {
+              id(nowcast_category).publish_state("Hazardous");
+            } else if (nowcast_calc <= 500.0) {
+              id(nowcast_category).publish_state("Hazardous"); // again
+            } else {
+              id(nowcast_category).publish_state("Hazardous"); // and again
+            }
+          } else {
+            int remaining_hours = hours_to_wait - std::max(size_2_5, size_10_0);
+            ESP_LOGD("custom", "No NowCast calculations available. %d hours remaining.", remaining_hours);
+            // Intervals don't quite overlap with the sensor notification windows,
+            // so let's readjust this just in case it's fallen out of sync.
+            id(nowcast_delay_mins) = 60 * remaining_hours;
+            id(nowcast_mins_remaining).publish_state(60 * remaining_hours);
+          }
+
 interval:
-  - interval: 5min
+  # Reset hardware watchdog. This varies between hardware. 3min should be plenty.
+  - interval: 3min
     then:
       - output.turn_on: watchdog
       - delay: 20ms
       - output.turn_off: watchdog
 
+  # Send data to AirGradient API server
+  # for more details have a look at sendToServer() function:
+  # https://www.airgradient.com/open-airgradient/blog/airgradient-diy-pro-instructions/
   - interval: 5min
-    # Send data to AirGradient API server
-    # for more details have a look at sendToServer() function:
-    # https://www.airgradient.com/open-airgradient/blog/airgradient-diy-pro-instructions/
     then:
       - http_request.post:
           # AirGradient URL with full MAC address in Hex format all lower case
-          url: !lambda |-
+          url: !lambda |
             return "http://hw.airgradient.com/sensors/airgradient:" + get_mac_address() + "/measures";
           headers:
-              Content-Type: application/json
+            Content-Type: application/json
           # "!lambda return to_string(id(pm2).state);" Converts sensor output from double to string
-          body: !lambda |-
+          # Note: can't use the built-in json encoder here because it does not support nested objects.
+          body: !lambda |
             String jsonString;
             StaticJsonDocument<1024> doc;
 
@@ -109,7 +412,10 @@ interval:
             doc["pm003_count"] = to_string(id(pm_0_3um).state);
             doc["atmp"] = to_string(id(temperature).state);
             doc["rhum"] = to_string(id(humidity).state);
-            doc["boot"] = "1";
+
+            // We don't have access to the boot loop counter in esphome, so just send a 1
+            // See: https://github.com/esphome/issues/issues/1539
+            doc["boot"] = "1"; 
 
             JsonObject channels = doc.createNestedObject("channels");
 
@@ -137,6 +443,19 @@ interval:
 
             return stdJsonString;
 
+  # Decrement the AQI countdowns once per minute until they reach zero
+  - interval: 1min
+    then:
+      - lambda: |
+          if (id(aqi_delay_mins) > 0) {
+            id(aqi_delay_mins) -= 1;
+            id(aqi_mins_remaining).publish_state(id(aqi_delay_mins));
+          }
+          if (id(nowcast_delay_mins) > 0) {
+            id(nowcast_delay_mins) -= 1;
+            id(nowcast_mins_remaining).publish_state(id(nowcast_delay_mins));
+          }
+
 light:
   - platform: status_led
     name: "Status LED"
@@ -153,6 +472,7 @@ binary_sensor:
         pullup: true
     on_click:
       min_length: 5s
+      max_length: 30s
       then:
         - button.press: button_restart
 
@@ -171,149 +491,285 @@ uart:
     rx_pin: GPIO0 # Pin 12
     tx_pin: GPIO1 # Pin 13
 
+text_sensor:
+  - platform: template
+    id: aqi_category
+    name: "${upper_devicename} AQI Category"
+    icon: "mdi:weather-windy-variant"
+    update_interval: 15min
+
+  - platform: template
+    id: nowcast_category
+    name: "${upper_devicename} NowCast Category"
+    icon: "mdi:weather-windy-variant"
+    update_interval: 15min
+
 sensor:
   - platform: pmsx003
     type: PMS5003T
     uart_id: uart_pm1
-    update_interval: 3min # Sensor will go into sleep mode for extended operation lifetime
+    update_interval: $pm_update_interval
     pm_1_0:
       id: pm1_1_0
       name: "${upper_devicename} Particulate Matter <1.0µm Concentration (1)"
+      disabled_by_default: true
     pm_2_5:
       id: pm1_2_5
       name: "${upper_devicename} Particulate Matter <2.5µm Concentration (1)"
+      disabled_by_default: true
     pm_10_0:
       id: pm1_10_0
       name: "${upper_devicename} Particulate Matter <10.0µm Concentration (1)"
+      disabled_by_default: true
     pm_0_3um:
       id: pm1_0_3um
       name: "${upper_devicename} Particulate Matter >0.3µm Count (1)"
+      disabled_by_default: true
     pm_0_5um:
       id: pm1_0_5um
       name: "${upper_devicename} Particulate Matter >0.5µm Count (1)"
+      disabled_by_default: true
     pm_1_0um:
       id: pm1_1_0um
       name: "${upper_devicename} Particulate Matter >1.0µm Count (1)"
+      disabled_by_default: true
     pm_2_5um:
       id: pm1_2_5um
       name: "${upper_devicename} Particulate Matter >2.5µm Count (1)"
+      disabled_by_default: true
     temperature:
       id: pm1_temperature
       name: "${upper_devicename} Temperature (1)"
+      disabled_by_default: true
     humidity:
       id: pm1_humidity
       accuracy_decimals: 1
       name: "${upper_devicename} Relative Humidity (1)"
+      disabled_by_default: true
 
   - platform: pmsx003
     type: PMS5003T
     uart_id: uart_pm2
-    update_interval: 3min # Sensor will go into sleep mode for extended operation lifetime
+    update_interval: $pm_update_interval
     pm_1_0:
       id: pm2_1_0
       name: "${upper_devicename} Particulate Matter <1.0µm Concentration (2)"
+      disabled_by_default: true
     pm_2_5:
       id: pm2_2_5
       name: "${upper_devicename} Particulate Matter <2.5µm Concentration (2)"
+      disabled_by_default: true
     pm_10_0:
       id: pm2_10_0
       name: "${upper_devicename} Particulate Matter <10.0µm Concentration (2)"
+      disabled_by_default: true
     pm_0_3um:
       id: pm2_0_3um
       name: "${upper_devicename} Particulate Matter >0.3µm Count (2)"
+      disabled_by_default: true
     pm_0_5um:
       id: pm2_0_5um
       name: "${upper_devicename} Particulate Matter >0.5µm Count (2)"
+      disabled_by_default: true
     pm_1_0um:
       id: pm2_1_0um
       name: "${upper_devicename} Particulate Matter >1.0µm Count (2)"
+      disabled_by_default: true
     pm_2_5um:
       id: pm2_2_5um
       name: "${upper_devicename} Particulate Matter >2.5µm Count (2)"
+      disabled_by_default: true
     temperature:
       id: pm2_temperature
       name: "${upper_devicename} Temperature (2)"
+      disabled_by_default: true
     humidity:
       id: pm2_humidity
       accuracy_decimals: 1
       name: "${upper_devicename} Relative Humidity (2)"
+      disabled_by_default: true
 
-    # Calculate the average sensor values
+  # Calculate the average values across both PMS5003T sensors
   - platform: template
     id: temperature
     name: "${upper_devicename} Temperature"
-    icon: mdi:home-thermometer-outline
+    icon: mdi:thermometer
     device_class: temperature
+    state_class: "measurement"
     accuracy_decimals: 1
     unit_of_measurement: "°C"
-    lambda: return (id(pm1_temperature).state + id(pm2_temperature).state) / 2;
+    lambda: return (id(pm1_temperature).state + id(pm2_temperature).state) / 2.0;
   - platform: template
     id: humidity
     name: "${upper_devicename} Relative Humidity"
     icon: mdi:water-percent
     device_class: humidity
+    state_class: "measurement"
     accuracy_decimals: 1
     unit_of_measurement: "%"
-    lambda: return (id(pm1_humidity).state + id(pm2_humidity).state) / 2;
+    lambda: return (id(pm1_humidity).state + id(pm2_humidity).state) / 2.0;
   - platform: template
     id: pm_1_0
     name: "${upper_devicename} Particulate Matter <1.0µm Concentration"
     icon: mdi:chemical-weapon
     device_class: pm1
+    state_class: "measurement"
     accuracy_decimals: 0
     unit_of_measurement: µg/m³
-    lambda: return (id(pm1_1_0).state + id(pm2_1_0).state) / 2;
+    update_interval: $pm_update_interval
+    lambda: return (id(pm1_1_0).state + id(pm2_1_0).state) / 2.0;
   - platform: template
     id: pm_2_5
     name: "${upper_devicename} Particulate Matter <2.5µm Concentration"
     icon: mdi:chemical-weapon
     device_class: pm25
+    state_class: "measurement"
     accuracy_decimals: 0
     unit_of_measurement: µg/m³
-    lambda: return (id(pm1_2_5).state + id(pm2_2_5).state) / 2;
+    update_interval: $pm_update_interval
+    lambda: return (id(pm1_2_5).state + id(pm2_2_5).state) / 2.0;
   - platform: template
     id: pm_10_0
     name: "${upper_devicename} Particulate Matter <10.0µm Concentration"
     icon: mdi:chemical-weapon
     device_class: pm10
+    state_class: "measurement"
     accuracy_decimals: 0
     unit_of_measurement: µg/m³
-    lambda: return (id(pm1_10_0).state + id(pm2_10_0).state) / 2;
+    update_interval: $pm_update_interval
+    lambda: return (id(pm1_10_0).state + id(pm2_10_0).state) / 2.0;
   - platform: template
     id: pm_0_3um
     name: "${upper_devicename} Particulate Matter >0.3µm Count"
-    icon: mdi:counter
+    icon: mdi:blur
     accuracy_decimals: 0
+    state_class: "measurement"
     unit_of_measurement: /dL
-    lambda: return (id(pm1_0_3um).state + id(pm2_0_3um).state) / 2;
+    update_interval: $pm_update_interval
+    lambda: return (id(pm1_0_3um).state + id(pm2_0_3um).state) / 2.0;
   - platform: template
     id: pm_0_5um
     name: "${upper_devicename} Particulate Matter >0.5µm Count"
-    icon: mdi:counter
+    icon: mdi:blur
     accuracy_decimals: 0
+    state_class: "measurement"
     unit_of_measurement: /dL
-    lambda: return (id(pm1_0_5um).state + id(pm2_0_5um).state) / 2;
+    update_interval: $pm_update_interval
+    lambda: return (id(pm1_0_5um).state + id(pm2_0_5um).state) / 2.0;
   - platform: template
     id: pm_1_0um
     name: "${upper_devicename} Particulate Matter >1.0µm Count"
-    icon: mdi:counter
+    icon: mdi:blur
     accuracy_decimals: 0
+    state_class: "measurement"
     unit_of_measurement: /dL
-    lambda: return (id(pm1_1_0um).state + id(pm2_1_0um).state) / 2;
+    update_interval: $pm_update_interval
+    lambda: return (id(pm1_1_0um).state + id(pm2_1_0um).state) / 2.0;
   - platform: template
     id: pm_2_5um
     name: "${upper_devicename} Particulate Matter >2.5µm Count"
-    icon: mdi:counter
+    icon: mdi:blur
     accuracy_decimals: 0
+    state_class: "measurement"
     unit_of_measurement: /dL
-    lambda: return (id(pm1_2_5um).state + id(pm2_2_5um).state) / 2;
+    update_interval: $pm_update_interval
+    lambda: return (id(pm1_2_5um).state + id(pm2_2_5um).state) / 2.0;
 
   - platform: wifi_signal
-    name: "Wifi Strength"
     id: airgradient_wifi_signal
-    update_interval: 60s
+    name: "Wifi Strength"
+    state_class: "measurement"
+    update_interval: 1min
 
   - platform: uptime
-    name: "Uptime Sensor"
     id: uptime_sensor
-    update_interval: 60s
+    name: "Uptime Sensor"
+    update_interval: 1min
+
+  - platform: template
+    id: aqi
+    name: "${upper_devicename} AQI"
+    device_class: aqi
+    state_class: "measurement"
+    icon: "mdi:weather-windy-variant"
+    accuracy_decimals: 0
+
+  - platform: template
+    id: nowcast
+    name: "${upper_devicename} NowCast"
+    device_class: aqi
+    state_class: "measurement"
+    icon: "mdi:weather-windy-variant"
+    accuracy_decimals: 0
+
+  - platform: template
+    id: aqi_mins_remaining
+    name: "AQI: Minutes Remaining"
+    icon: mdi:timer-sand
+    accuracy_decimals: 0
+    unit_of_measurement: minutes
+
+  - platform: template
+    id: nowcast_mins_remaining
+    name: "NowCast: Minutes Remaining"
+    icon: mdi:timer-sand
+    accuracy_decimals: 0
+    unit_of_measurement: minutes
+
+  - platform: copy
+    source_id: pm_2_5
+    id: pm_2_5_1h_avg
+    name: "${upper_devicename} PM <2.5µm 1h Average"
+    disabled_by_default: true
+    device_class: pm25
+    accuracy_decimals: 1
+    filters:
+      - sliding_window_moving_average:
+          window_size: 20 # every 3 minutes = 1 hour
+          send_every: 20
+          send_first_at: 20
+    on_value:
+      lambda: |
+        // Insert the current value
+        float current = id(pm_2_5_1h_avg).state;
+        if (!isnan(current)) {
+          id(pm_2_5_hourly_avg).insert(id(pm_2_5_hourly_avg).begin(), current);
+          // Truncate anything past the first 24
+          if (id(pm_2_5_hourly_avg).size() > 24) {
+            id(pm_2_5_hourly_avg).resize(24);
+          }
+        }
+        ESP_LOGD("custom", "pm_2_5_hourly_avg size: %d", id(pm_2_5_hourly_avg).size());
+
+        // Trigger the AQI calculations (they'll restart if the pm10 finishes slightly later)
+        id(calculate_nowcast).execute();
+        id(calculate_aqi).execute();
+
+  - platform: copy
+    source_id: pm_10_0
+    id: pm_10_0_1h_avg
+    name: "${upper_devicename} PM <10.0µm 1h Average"
+    disabled_by_default: true
+    device_class: pm10
+    accuracy_decimals: 1
+    filters:
+      - sliding_window_moving_average:
+          window_size: 20 # every 3 minutes = 1 hour
+          send_every: 20
+          send_first_at: 20
+    on_value:
+      lambda: |
+        // Insert the current value
+        float current = id(pm_10_0_1h_avg).state;
+        if (!isnan(current)) {
+          id(pm_10_0_hourly_avg).insert(id(pm_10_0_hourly_avg).begin(), current);
+          // Truncate anything past the first 24
+          if (id(pm_10_0_hourly_avg).size() > 24) {
+            id(pm_10_0_hourly_avg).resize(24);
+          }
+        }
+        ESP_LOGD("custom", "pm_10_0_hourly_avg size: %d", id(pm_10_0_hourly_avg).size());
+
+        // Trigger the AQI calculations (they'll restart if the pm2.5 finishes slightly later)
+        id(calculate_nowcast).execute();
+        id(calculate_aqi).execute();
diff --git a/air-gradient-pro-diy.yaml b/air-gradient-pro-diy.yaml
index dbed031..6dabed9 100644
--- a/air-gradient-pro-diy.yaml
+++ b/air-gradient-pro-diy.yaml
@@ -1,10 +1,21 @@
 # AirGradient Pro v4.2 DIY edition
 #
+# Upstream AirGradient Firmware can be found here:
+# https://github.com/airgradienthq/arduino/blob/master/examples/DIY_PRO_V4_2/DIY_PRO_V4_2.ino
+#
+# Instructions:
+# - Update your device id in `substitutions`
+# - Select your temperature unit in `substitutions`
+# - If you have the VOC/NOx sensor installed, uncomment `platform: sgp4x` and page3 of `display`
+#
 
 substitutions:
   id: "1"
   devicename: "airgradient-pro"
   upper_devicename: "AirGradient Pro"
+  # Pick your temperature unit:
+  # temperature_units: "F"
+  temperature_units: "C"
 
 esphome:
   name: "${devicename}-${id}"
@@ -17,6 +28,7 @@ esphome:
 
 # Enable logging
 logger:
+  baud_rate: 0
 
 # Enable Home Assistant API (API password is deprecated in favor of encryption key)
 # https://esphome.io/components/api.html
@@ -29,8 +41,8 @@ ota:
 
 wifi:
   networks:
-  - ssid: !secret wifi_ssid
-    password: !secret wifi_password
+    - ssid: !secret wifi_ssid
+      password: !secret wifi_password
   reboot_timeout: 15min
 
   # Enable fallback hotspot (captive portal) in case wifi connection fails
@@ -38,9 +50,9 @@ wifi:
     ssid: "${upper_devicename} Fallback Hotspot"
     password: !secret fallback_ssid_password
 
-# Used to support POST request to send data to AirGradient
-# https://esphome.io/components/http_request.html
-http_request:
+# The captive portal is a fallback mechanism for when connecting to the configured WiFi fails.
+# https://esphome.io/components/captive_portal.html
+captive_portal:
 
 # Creates a simple web server on the node that can be accessed through any browser
 # https://esphome.io/components/web_server.html
@@ -48,9 +60,9 @@ web_server:
   port: 80
   include_internal: true
 
-# The captive portal is a fallback mechanism for when connecting to the configured WiFi fails.
-# https://esphome.io/components/captive_portal.html
-captive_portal:
+# Used to support POST request to send data to AirGradient
+# https://esphome.io/components/http_request.html
+http_request:
 
 # Create a switch for safe_mode in order to flash the device
 # Solution from this thread:
@@ -64,14 +76,48 @@ i2c:
   sda: D2
   scl: D1
 
-# Monofonto by Typodermic Fonts: https://typodermicfonts.com/monofonto/
-# alternative download: https://www.fontsaddict.com/font/monofonto.html
 font:
-  - file: "fonts/monofont.ttf"
-    id: opensans
-    size: 12
+  - file: "gfonts://Ubuntu"
+    id: font_data
+    size: 18
+  - file: "gfonts://Ubuntu"
+    id: font_layout
+    size: 10
+    glyphs: # We only need a subset of glyphs
+      - " "
+      - "."
+      - "/"
+      - "°"
+      - "0"
+      - "1"
+      - "2"
+      - "₂"
+      - "³"
+      - "%"
+      - "5"
+      - "C"
+      - "d"
+      - "e"
+      - "F"
+      - "g"
+      - "H"
+      - "i"
+      - "m"
+      - "M"
+      - "N"
+      - "O"
+      - "p"
+      - "P"
+      - "t"
+      - "T"
+      - "u"
+      - "V"
+      - "x"
+      - "y"
+      - "µ"
 
 display:
+  # https://esphome.io/components/display/ssd1306.html
   - platform: ssd1306_i2c
     id: oled
     address: 0x3c
@@ -79,14 +125,44 @@ display:
     pages:
       - id: page1
         lambda: |-
-          it.printf(0, 0, id(opensans),  "CO2:         %3.0f ppm", id(co2).state);
-          it.printf(0, 10, id(opensans), "PM 1.0:      %3.0f ppm", id(pm_1_0).state);
-          it.printf(0, 20, id(opensans), "PM 2.5:      %3.0f ppm", id(pm_2_5).state);
-          it.printf(0, 30, id(opensans), "PM 10:       %3.0f ppm", id(pm_10_0).state);
-          it.printf(0, 40, id(opensans), "Humidity:     %2.2f %%", id(humidity).state);
-          it.printf(0, 50, id(opensans), "Temperature:  %2.2f C", id(temp).state);
-      # - id: page2
+          it.print(51, 2, id(font_layout), TextAlign::TOP_RIGHT, "CO₂");
+          it.printf(it.get_width() - 30, 18, id(font_data), TextAlign::BOTTOM_RIGHT, isnan(id(co2).state) ? "N/A" : "%.0f", id(co2).state);
+          it.print(it.get_width() - 28, 16, id(font_layout), TextAlign::BOTTOM_LEFT, "ppm");
+
+          it.print(50, 25, id(font_layout), TextAlign::TOP_RIGHT, "Temp.");
+          float degrees = "${temperature_units}" == "F" ? id(temp).state * 1.8 + 32.0 : id(temp).state;
+          it.printf(it.get_width() - 30, 41, id(font_data), TextAlign::BOTTOM_RIGHT, "%.0f", degrees);
+          it.print(it.get_width() - 28, 39, id(font_layout), TextAlign::BOTTOM_LEFT, "°${temperature_units}");
+
+          it.print(50, 48, id(font_layout), TextAlign::TOP_RIGHT, "Humidity");
+          it.printf(it.get_width() - 30, 64, id(font_data), TextAlign::BOTTOM_RIGHT, "%.0f", id(humidity).state);
+          it.print(it.get_width() - 28, 62, id(font_layout), TextAlign::BOTTOM_LEFT, "%");
+          // This no longer fits on the page. You're on your own if you've added a nonstandard PMSX003* with formaldehyde sensor.
+          // it.printf(0, 40, id(font_data), isnan(id(hcho).state) ? "HCHO: N/A" : "HCHO: %.0f µg/m³", id(hcho).state);
+      - id: page2
+        lambda: |-
+          it.print(50, 2, id(font_layout), TextAlign::TOP_RIGHT, "PM 1.0");
+          it.printf(it.get_width() - 30, 18, id(font_data), TextAlign::BOTTOM_RIGHT, isnan(id(pm_1_0).state) ? "N/A" : "%.0f", id(pm_1_0).state);
+          it.print(it.get_width() - 28, 16, id(font_layout), TextAlign::BOTTOM_LEFT, "µg/m³");
+
+          it.print(50, 25, id(font_layout), TextAlign::TOP_RIGHT, "PM 2.5");
+          it.printf(it.get_width() - 30, 41, id(font_data), TextAlign::BOTTOM_RIGHT, isnan(id(pm_2_5).state) ? "N/A" : "%.0f", id(pm_2_5).state);
+          it.print(it.get_width() - 28, 39, id(font_layout), TextAlign::BOTTOM_LEFT, "µg/m³");
+
+          it.print(50, 48, id(font_layout), TextAlign::TOP_RIGHT, "PM 10");
+          it.printf(it.get_width() - 30, 64, id(font_data), TextAlign::BOTTOM_RIGHT, isnan(id(pm_10_0).state) ? "N/A" : "%.0f", id(pm_10_0).state);
+          it.print(it.get_width() - 28, 62, id(font_layout), TextAlign::BOTTOM_LEFT, "µg/m³");
+      # - id: page3
       #   lambda: |-
+      #     it.print(51, 2, id(font_layout), TextAlign::TOP_RIGHT, "CO₂");
+      #     it.printf(it.get_width() - 30, 18, id(font_data), TextAlign::BOTTOM_RIGHT, isnan(id(co2).state) ? "N/A" : "%.0f", id(co2).state);
+      #     it.print(it.get_width() - 28, 16, id(font_layout), TextAlign::BOTTOM_LEFT, "ppm");
+
+      #     it.print(50, 25, id(font_layout), TextAlign::TOP_RIGHT, "VOC");
+      #     it.printf(it.get_width() - 30, 41, id(font_data), TextAlign::BOTTOM_RIGHT, isnan(id(voc).state) ? "N/A" : "%.0f", id(voc).state);
+
+      #     it.print(50, 48, id(font_layout), TextAlign::TOP_RIGHT, "NOx");
+      #     it.printf(it.get_width() - 30, 64, id(font_data), TextAlign::BOTTOM_RIGHT, isnan(id(nox).state) ? "N/A" : "%.0f", id(nox).state);
 
 interval:
   - interval: 10s
@@ -104,7 +180,7 @@ interval:
           url: !lambda |-
             return "http://hw.airgradient.com/sensors/airgradient:" + get_mac_address().substr(6,11) + "/measures";
           headers:
-              Content-Type: application/json
+            Content-Type: application/json
           # "!lambda return to_string(id(pm2).state);" Converts sensor output from double to string
           json:
             wifi: id(airgradient_wifi_signal).state
@@ -115,8 +191,9 @@ interval:
             rco2: !lambda return to_string(id(co2).state);
             atmp: !lambda return to_string(id(temp).state);
             rhum: !lambda return to_string(id(humidity).state);
-            # tvoc: !lambda return to_string(id(tvoc).state);
+            tvoc: !lambda return to_string(id(voc).state);
           verify_ssl: false
+
 uart:
   - rx_pin: D5
     tx_pin: D6
@@ -129,6 +206,7 @@ uart:
     id: uart_2
 
 sensor:
+  # https://esphome.io/components/sensor/sht3xd.html
   - platform: sht3xd
     temperature:
       id: temp
@@ -139,6 +217,7 @@ sensor:
     address: 0x44
     update_interval: 10s
 
+  # https://esphome.io/components/sensor/pmsx003.html
   - platform: pmsx003
     type: PMSX003
     uart_id: uart_1
@@ -154,20 +233,26 @@ sensor:
     pm_0_3um:
       id: pm_0_3um
       name: "${upper_devicename} Particulate Matter >0.3µm Count"
+      icon: mdi:blur
     pm_0_5um:
       id: pm_0_5um
       name: "${upper_devicename} Particulate Matter >0.5µm Count"
+      icon: mdi:blur
     pm_1_0um:
       id: pm_1_0um
       name: "${upper_devicename} Particulate Matter >1.0µm Count"
+      icon: mdi:blur
     pm_2_5um:
       id: pm_2_5um
       name: "${upper_devicename} Particulate Matter >2.5µm Count"
+      icon: mdi:blur
+    # The basic PMSX003 version doesn't have a formaldehyde sensor.
     # formaldehyde:
     #   id: hcho
-    #   name: "{upper_devicename} Formaldehyde (HCHO) concentration in µg per cubic meter"
+    #   name: "${upper_devicename} Formaldehyde (HCHO) concentration in µg per cubic meter"
     update_interval: 3min # Sensor will go into sleep mode for extended operation lifetime
 
+  # https://esphome.io/components/sensor/senseair.html
   - platform: senseair
     uart_id: uart_2
     co2:
@@ -175,6 +260,26 @@ sensor:
       name: "${upper_devicename} SenseAir CO2 Value"
     update_interval: 60s
 
+  # https://esphome.io/components/sensor/sgp4x.html
+  # https://sensirion.com/products/catalog/SGP41/
+  # Note that these "index" values don't have a unit. They are a scale from 1-500.
+  # - platform: sgp4x
+  #   voc:
+  #     id: voc
+  #     name: "VOC Index"
+  #     icon: mdi:chemical-weapon
+  #     # See https://sensirion.com/media/documents/02232963/6294E043/Info_Note_VOC_Index.pdf
+  #     # 0-150 green, 151-250 yellow, 251-400 orange, 401+ red
+  #   nox:
+  #     id: nox
+  #     name: "NOx Index"
+  #     icon: mdi:chemical-weapon
+  #     # See https://sensirion.com/media/documents/9F289B95/6294DFFC/Info_Note_NOx_Index.pdf
+  #     # 0-19 green, 20+ yellow (see PDF for why we don't do more than this)
+  #   compensation:
+  #     humidity_source: humidity
+  #     temperature_source: temp
+
   - platform: wifi_signal
     name: "WiFi Signal Sensor"
     id: airgradient_wifi_signal
diff --git a/secrets.yaml b/secrets.yaml
index cc070e2..be84216 100644
--- a/secrets.yaml
+++ b/secrets.yaml
@@ -6,4 +6,7 @@ wifi_password: ""
 ota_password: ""
 
 #AP
-fallback_ssid_password: ""
\ No newline at end of file
+fallback_ssid_password: ""
+
+# Encryption key for Home Assistant integration
+home_assistant_encryption_key: ""
\ No newline at end of file