Anybody know where the Gorge forecaster gets their flow data

[johnl]

I've been watching the Gorge forecast a lot lately (like most of you) and I'm baffled by the forecast. Specifically the John Day flow. Today (6/15/14) forecast said "Columbia River Peak Flow rate at John Day Dam ~260 cfs".

First of all I think it is awesome that they add this since it helps determine if I'm going to drive to Maryhill or Rufus. But unfortunately this conflicts with my sources.

http://www.nwrfc.noaa.gov/river/station/flowplot/flowplot.cgi?JDAO3

This shows the INFLOW (ie water coming INTO the dam) as approximately 240k cfs which would somewhat match the forecast. BUT the DISCHARGE (ie water going out of the dam and heading to Rufus, the Wall, and Maryhill) was 201k cfs @0800 PDT which is quite a difference.

Anybody else have any input on this? Such as maybe I'm using the wrong source (I doubt) or reading it wrong (I really hope not)?

[gmclean]

I think discharge is what is important but this probably requires more research in the field

[mcterry65]

http://www.nwd-wc.usace.army.mil/ftppub/project_data/hourly/jda_0daysback.txt

[30knotwind]

I have a forecast page:
http://www.30knotwind.com/p/river-discharge-forecasts.html

John Day data:
http://www.nwd-wc.usace.army.mil/report/jda.htm

Actual data at The Dalles:
Chart

Table

[johnl]

Thanks 30knowt, but your flows are high also. They are showing 240ish for today when the reality is the flows (by my NOAA source and MCTerry) are closer to the 200k cfs range. Yours seems to share the same flow rate as the Gorge Forecaster, HOWEVER I did notice that the forecast flow dropped significantly in the current forecast. Maybe the forecaster noticed they were reading the inflow and not the discharge?

[Temira]

Hi all. Temira here. I get mine from these links:

John Day
http://www.nwd-wc.usace.army.mil/ftppub/project_data/hourly/jda_0daysback.txt

The Dalles
http://waterdata.usgs.gov/or/nwis/current/?type=flow

I don't know if they're spot-on, but they do change from day to day, and do seem to reflect the changes I see in the river.

FYI, flow on SuperTuesday was around 363kcfs.

How about all this wind?

=)

[johnl]

From what I've seen they can change quite a bit during the day also But I was comparing the data I was seeing @0800 vs the forecast (probably 0600 or so). That should be fairly close But it wasn't

[30knotwind]

Johnl, your page shows similar observations to the forecast, although I was assuming the forecaster was publishing the observed data since the temperature data is an observation.
http://www.nwrfc.noaa.gov/station/flowplot/textPlot.cgi?id=JDAO3&pe=QR

Note that this morning it is already below 200 KCFS
-Chris

[johnl]

Thanks Crysta you gave me a good laugh reading the forecast. Nice to see you are lurking in the forums...