I wouldn't say the Atlas rain rate is dubious, rather it reflects something different than instantaneous rain rate. What it shows is the total accumulation for the past hour. It is real accumulated rainfall amount rather than a projected rainfall rate.
If that is true, then it would be a bug in the Atlas display, as Acurite displays have never displayed rain rate based on an hour accumulation.
That is exactly what Acurite is doing, a rate based on the past hour accumulation, with a decay down to zero on inactivity of rain after a certain number of minutes. That period of inactivity and then potential restart would indicate the beginning of the next rain event. So as long as it continues to rain (no break) for a full hour then the rain rate continues to increase, faster or slower and lining up exactly the same as total rainfall amount. Then after the full hour of non-stop rain if it still continues to rain then only the total of the past hour is considered in the rain rate reported...which could mean that depending on if it has begun to slow down or actually increase in intensity the rain rate after and hour could continue to increase or decrease accordingly. So after an hour the curves match perfectly in nonstop rain. After that hour the curves usually separate because of how only the previous full hour is considered in the calculation.
It's always been something short of 15 minutes before it starts to update, as per the documentation I posted earlier.
Okay yes...but also what I said before.
And as I've stated before, Acurite and other brands do not send "rain rate" to wunderground.
From looking at raw data coming from Ambient and others rain rate is sent to wunderground. Here is a raw data from Ambient:
GET /weatherstation/up
dateweatherstation.php?ID=STATIONID&PASSWORD=PLAINTEXTPASSWORD&tempf=43.3&h
umidity=98&dewptf=42.8&windchillf=43.3&winddir=129&windspeedmph=0.00&
windgustmph=0.00&rainin=0.00&dailyrainin=0.04&weeklyrainin=0.04&month
lyrainin=0.91&yearlyrainin=0.91&solarradiation=0.00&UV=0&indoortempf=
76.5&indoorhumidity=49&baromin=29.05&lowbatt=0&dateutc=2016-1-4%2021:
2:35&softwaretype=WH2602%20V4.4.7&action=updateraw&realtime
=1&rtfreq=5 HTTP/1.0
Host: https://rpupdate.wunderground.com
rainin= is rain rate
dailyrain= is the total rain for the day which increases as it rains...and stays the same if it stops and only resets at midnight.
So yes, Ambient does report rain rate. It is just a different rain rate calculation based on instant rain rate rather than previous hour total. There are only two ways to do it that I've seen. And as I've said before neither is more correct than the other...they just tell a different story. I have no idea what Acurite sends or doesn't. If Acurite in fact doesn't send rain rate as you state then it could be then that Weather Underground is calculating it for you based on dailyrain input...and it may be then that Weather Underground is defaulting to using the accumulated past hour method. If that is the case then all that Acurite needs to do is calculate rain rate on the instant rain rate method and pass that along so that Weather Underground doesn't calculate it for them using the other method. I think it would be even better if Acurite offered this as an option as other 3rd party weather software does.
Your conclusion is false.
You could have stated that a bit nicer, like, "I think your conclusion is false." Or just don't even have that kind of talk which creates conflict. My conclusion is not false, it has merit as do also your viewpoints which I respect. When I'm wrong I have no problem admitting it. It is all still meaningful useful dialog because if I think this way, there is a good chance someone else also thinks this way, and then everyone learns when things are discussed. Let's be a united community that helps each other instead of at each other's throats.
Peace
I'm sorry, but you simply do not understand how it works. The Acurite displays do not use a one-hour accumulation. Period.
As I told you before, the wunderground upload protocol specifies "rainin" as being the amount of rain that has fallen in the past 60 minutes. I even indicted that it is a "rate", but not an instantaneous one. Each display has its own time period for breaking it down further, typically something between 6 and 15 minutes depending on the brand.
While this has nothing to do with the display, wunderground takes that info and determines *their* rain rate based upon it. Ambient, Davis, Acurite... they're all sending the same type of data, the only difference being if they are conforming to wunderground's protocol or not.
As you say, you don't know what Acurite is sending, but it's all in the protocol. As far as rain reporting goes, Acurite is doing it EXACTLY as wunderground wants them to. You can theorize all you want, but that doesn't make your theories correct. The only thing different you can do is violate the protocol and change "rainin" to fit your fancy.
Acurite isn't calculating the shown rain rate. Neither is anyone else reporting that. They just report rain accumulated in the past 60 minutes, and wunderground takes it from there with their own processing to make it look "instantaneous" by breaking it down into a shorter time period. I don't know how to explain it any simpler.
Granted, they can play around with "rainin" and report a different amount, so as to impact the graphs, but it's not standard.
The folks at Wunderground weren't idiots when they set up this up. They knew they had to contend with the variances of different brands, and this protocol is what they came up with. It's not perfect, but it is consistent.
Acurite is reporting to wunderground exactly as they are supposed to be reporting with respect to rainfall. "rainin" is supposed to be accumulation of the past 60 minutes for EVERYBODY.
It's just that simple.
Here's the relevant quote, again, from the protocol page:
rainin - [rain inches over the past hour)] -- the accumulated rainfall in the past 60 min
dailyrainin - [rain inches so far today in local time]
If wunderground wants to start endorsing some other period than 60 minutes, then I will accept that. It's their protocol, written for a reason by knowledgeable people. Other's shouldn't be disregarding it because they think it makes their graphs pretty.
Have you ever seen rain rate calculated in davis console? If so, do you have more information of the formula they have used?
I have no idea what WU does with it, this is how it works in house.
BTW, thanks to "galfert" for the link.
RAINFALL RATE
Parameters Used: Rain Total (actually, rain rate is a measured variable in the sense that it is
measured by the ISS and transmitted to the display console, whereas all other calculated
variables are determined by the console from data received from the ISS.)
Formula:
Under normal conditions, rain rate data is sent with a nominal interval of 10 to 12 seconds.
Every time a rain tip or click occurs, a new rain
rate value is computed (from the timer values)
and the rate timers are reset to zero.
Rain rate is calculated based on the time between successive tips of the rain collector. The rain
rate value is the highest rate since the last transmitted rain rate data packet. (Under most
conditions, however, a rain tip will not occur every 10 to 12 seconds.)
If there have been no rain tips since the last rain rate data transmission, then the rain rate based
on the time since that last tip is indicated. This results in slowly decaying rate values as a rain
storm ends, instead of showing a rain rate which abruptly drops to zero. This results in a more
realistic representation of the actual rain event.
If this time exceeds roughly 15 minutes, than the rain rate value is reset to zero. This period of
time was chosen because 15 minutes is defined by the U.S. National Weather Service as
intervening time upon which one rain "event" is considered separate from another rain "event".
This is also the shortest period of time that the Umbrella will be seen on the display console
after the onset of rain.
REFERENCES
"Surface Weather Observations and Reports ". Office of the Federal Coordinator for
Meteorological Services and Supporting Research, Washington, DC, 1998