Comparing my rainfall amounts with NOAA sites, I notice I record as much as double everyone elses reported amounts. I have used alternate methods of recording rainfall at my site and other locations near me and they agree with my station amounts. Yesterday my station recorded 2.35 inches of rain. Checking the NOAA precipitation reports for my area shows the highest reported amount to be 1.26 inches. Personal and airport weather stations in my area also report rain amounts much lower than my station. Does anyone know where the NOAA acquires it’s data from, and, how they measure rainfall amounts? Is anyone else seeing the same thing in their area?
NOAA should get there data from nws ASOS stations(METER airport), CWOP stations (stations reported by volenters), and maybe RAWS stations(used mostly in the west for fire management in remote areas). Just because you record much more, doesn’t mean you are wrong. Unless they are within a very small distance to you, you could easily get that much more than them.
more info:
http://www.nws.noaa.gov/asos/index.html
http://www.nws.noaa.gov/om/coop/Publications/cssamanual.pdf
http://www.fs.fed.us/raws/
Just because you record much more, doesn't mean you are wrong. Unless they are within a very small distance to you, you could easily get that much more than them.
If it was once or twice I could understand. This is constant, every rain event. More often than not I have double the amount they report. I have checked my data against metars and other personal weather stations near me and it’s always the same.
I bought a glass rain gauge to compare to my WMII and they agree on rain amounts. 2 people I work with have glass rain gauges and our readings are always within a tenth of inch for totals. I am confident that my amounts are correct.
If NOAA does use CW for their data, and they saw my reported data, and then compared mine to other stations, I am sure they would discard my data as erroneous due to the huge difference (an inch of rain qualifies as a huge). Most of the error check programs I have tried use this comparison method to validate input to their databases. If everybody reports around an inch of rain, and one guy reports 2+ inches, then obviously he’s wrong.
I just wanted to know if anyone else has done comparisons of their weather station versus NOAA reported rainfall amounts for their area and if they noticed the same thing.
NOAA also has observers, volunteers. I was thinking about inquiring to see if I would qualify and what they expect. Does anyone here have experience with this program?
rainfall does vary alot, in an area, you will be surprised…
local terrain can cause this, microclimates, etc
not sure if or how they would decide to discard your readings or not
heading out for the day, have to help me mum with some things
i have noticed some difference, but my manual rain gage agrees as well, so I am confident as well.
Actually when I said CWOP I meant Co-op. I would say all of them are accurate, and you happen to be in a certain “micro-climate” as brian said.