I'm learning a lot about the lack of air quality data in rural areas. I am going to buy a Purple Air monitor and get it installed somewhere around here. We probably need more than one.
I first noticed some oddities comparing the air quality maps from Apple and Weatherbug. This was July 26. That was the day I woke up with chest congestion when I was sleeping outdoors on the screen porch.
You'll notice that Apple, on the left, was saying 135 and Weatherbug, on the right, was saying 68. It's hard to reconcile these maps; tho, given how I felt waking up that morning, I'm pretty clear that Weatherbug was lowballing it.
The air cleared up for a while after that, but then got bad again.
I had some conversations with Grok to help me learn more. Grok introduced me to two websites that sell air quality monitors and then publish the results on maps
iqair.com
purpleair.com
After talking to Grok, I made an air quality collage (August 3, 2025):
Top (left to right)
- IQAir, showing several monitors nearby ranging from 63-147
- Purple Air, showing monitors raning from 116-126
- Weather bug showing the absurdly low value of 38
- AirNow (federal) showing no data for Randolph, but a forecast of 101
Bottom
- local mountains very hazy
- Apple air quality map, showing 74, which I also think was absurd, because the moon was orange, and I got a sore throat going out without a mask
Grok says that Apple uses an AI engine called "breezometer" to estimate air quality where there are no monitors. Grok said it was unlikely that this AI engine could accurately estimate air quality with multiple mountain ranges and micro-climates.
Summary
no real data for most of Coös County NH
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Here was my second day of trying to evaluate this (August 4, 2025)
top (left to right)
- WeatherBug 49 (again absurdly low)
- AirNow (federal govt) no data for Randolph. this collage cut off the forecast, but it was 103
- IQAir ranging from 85-167 around here
bottom
- Purple Air ranging from 70-159 -- with the closest monitors all over 150
- Apple at 101
- photo of mountains even more hazy
August 5-6, 2025
Orange Moon
I tried to capture a snapshot of the moon looking orange. Now normally, when I try to take a picture of the moon with this cell phone, I get a featureless white disk. I don't see any of the normal moon markings. This particular evening (August 5), because the moon was dimmed by smoke, the camera could capture features. Unfortunately, at this magnification, I couldn't hold the camera still enough to get a clear picture, but maybe you can get the idea.
Normally, I'm in the NYC metro area, where there are a lot more monitors. I trust the estimates of air quality there more, because there is more data. I can assure you that the moon is not orange at an air quality of 72 down there.
Another collage (August 6)
- IQ Air ranging from 26-139
- Weatherbug again lowballing it at 36
- Apple at 72
- Purple Air ranging from 98-135
August 8
Today (August 8, below) I learned about a new App, Weather Underground, that is estimating higher than some others. It's got 159 at the top for my community. That's the highest estimate I've seen, but it makes some sense because this is a mountain valley. Grok pointed out that valleys tend to accumulate pollutants.
otherwise
- AirNow no data but forecasting 55
- Apple at 70
- Weatherbug at 50
- IQair ranging from 67-110 nearby, with bigger variations farther away
- PurpleAir from 24-126
I feel communities in mountain valleys, like Randolph NH, really need their own air quality monitors in order to get accurate air quality data during smoke situations like we've been having in early August 2025
Another thing I’ve been watching this week is the wind patterns around here. Apple has a wind pattern map. I had once heard a discussion by a meteorologist associated with the weather observatory on the top of Mount Washington. He said that there were three major wind systems that were interrupted by the Presidential Range. I could really see that on the Apple map. For several days there was wind from three directions all blowing towards the Presidential mountains. There seem to be a system east of here, a system north of here, and a system south of here. After a while, the system east of here started blowing through so that area is now green on the maps. However, the area north of here has had wind blowing south and the area south of here has had wind blowing north, so that the air was stagnating here around Randolph.
Today, the wind is blowing pretty steadily from the south, but that is substantially blocked, by the Presidential Range here.
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August 9
- Wunderground 165 (this seems to be an outlier. I wonder if they actually know where Randolph NH is, or whether they are really doing some kind of special calculation relating to our local mountainous conditions)
- Airnow no data, but forecasting 51 from NH weather service
- Apple Weather 56 (uses Breezometer)
- Weatherbug 47 ( they’ve consistently had the lowest value. I wonder if they have the wrong location for Randolph, NH)
- Purple Air — nearest sensor near Littleton “middle beach hill” 83; also to the north, near Canada “murphy dam” 71; Bartlett NH 59; Rumford, ME (4 sensors 54,57,59, 71)
- IQAir ledgewood drive, Littleton NH 81; Murphy Dam Road, Colebrook 69
I did some research and found that the Wunderground says their information is from the Copernicus website https://climate.copernicus.eu/
Copernicus has world wide forecasts for several different pollutants: aerosols, carbon dioxide, carbon monoxide, formaldehyde, methane, nitrogen dioxide, and ozone https://atmosphere.copernicus.eu/global-forecast-plots
I spent some time conversing with Grok about whether Breezometer or Copernicus was more accurate. Breezometer claims to be accurate down to 5m, while Copernicus only has a 40km resolution. Otoh, my impression is that during the recent smoke events the value cited by Apple has been way too low on bad days. This is likely due to the mountainous conditions and lack of local data around Randolph, NH.
Still being puzzled about how Weather Underground (wunderground app) got such a high level, I went to the Copernicus website, where Wunderground says they get their data. I see this map for aerosols, which I think woodsmoke is
It's a little hard to interpret this, because it's not US units, but it's hard to see that this would be as bad as 165, which is what the wunderland app is saying on iphone at approximately 4:45 pm Eastern Time August 9.
I also went to the Weather underground website to see their local sensors. I got this map
In the vicinity of Randolph, NH, the values are in the 80's and 90's. Granted Randolph is in a mountain valley, so particulates could accumulate here, but it's hard to see how they came up with 165.
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August 11, 2025
Here is today's air quality collage with annotations. At least they mostly seem in agreement that the air is in the moderate range, except for the perpetually optimistic Weatherbug. Still I was coughing in Gorham, NH without a mask.
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Link to NH state weather information
It appears that there are some air quality monitoring devices on Mt Washington, but that they only have ozone data.
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August 14
We had some rain, but the numbers aren't as much better as I might have hoped.
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#AirQuality #CanadianWildfires #Breezometer #WeatherBug #WeatherUnderground #Wunderground #AirNow #PurpleAir #IQAir #AppleWeatherApp #CoösCountyNH #RandolphNH
