MesoWest CWOP Data NOT matching Weatherflow Data

I finally managed to get my data synced up to CWOP and it is now showing up on MesoWest. However, my rainfall total since midnight shows up as 0.99" here: And on MesoWest ( it shows the total rainfall since midnight as 0.75". The 0.75" is actually more likely close to the observed rainfall, while the 0.99" is definitely too high. I have a 4" gauge that was around 0.74".

Perhaps the learning algorithm has been implemented on data that is sent elsewhere but is not showing up on the local console or something weird like that? Anyone have any ideas why the precipitation would be different? Everything else matches up perfectly. Thanks!

What rain amount did you send in the cwop packet?

I’m not sure what you mean? When I set it all up I specified US units and that was it. I am using weewx to get it to the CWOP database.

What is your CWOP ID?

My CWOP ID is FW3071.

It was sending .75 and just jumped to .76. The last 24 hours was .81.

So the next step would be to check the data from WeatherFlow and see what it adds up to.

Correct. I checked the Weatherflow data and it added up to 0.99" (now 1.01"). This is the same number that is showing on the Weatherflow home page for my station (as well as on the app).

Maybe a bug in weewx.

Perhaps. What is really weird is that someone else posted that they were having similar issues with a different service. Also, the numbers that are being shown in the CWOP database are basically correct (within a couple hundredths), while the numbers on the Weatherflow station are several tenths too high. Strange.

Correct or not, weewx should match WeatherFlow

udp drop outs ?? Since weewx is catching that strain of data … micro cuts …??

Do you have an idea to test, better then using wireshark with stupid manually observation?
Does someone know a logic / timeframing behind the UDP transmissions ? Hence one could be able to do the analysis automatically …

The only way is to capture the UDP data and store it. You can compare it with the data store on the WeatherFlow servers.

So the WFarchive(r) has the capabilities ?! :wink:

Yes, it stores UDP data and has the capability to download and store the data from WestherFow servers.

From the weewx UDP driver readme…

log_raw_packets = False

Enable writing all raw UDP packets received to syslog,
(or wherever weewx is configured to send log info).  Will
fill up your logs pretty quickly, so only use it as
a debugging tool or to identify sensors.

I have had problems with the weatherflowUDP driver partially missing or completely missing obs at times. The missed data doesn’t get written to the weewx database and thus the data at CWOP/Mesowest tends to be differnt than the weatherflow station measurements. I haven’t been able to figure out why the data gets missed. I noticed your station has the same issue at times.

Here is my data on mesowest.

How did you reach the conclusion that the weewx driver was missing broadcast data ?

CWOP being different is not necessarily an indication that weewx didn’t receive and ‘send’ that data to them. All these online places drop data (WU is particularly bad in that respect, ignoring all the policy complaints people have about them).

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Sure - look at the UDP API for what’s broadcast and how often.

I’d suggest that part is far easier said than done…

What is the data missing from?

I have been collecting the WeatherFlow UDP data for months and have had no unexplained issues.