Robert,
The link that I provided is an Aviation Weather Report supplied by Weather Bureau to the FBI. The reporting stations are airports. There is even a section entited "PIREPS" which, as you know, stands for Pilot Reports".
did you even bother to look at it or had you made up your mind already?
Further, the data of the winds aloft provided by Tom Kaye is from the ground to 12,000 feet AMSL.
Lastly, what you are saying is irrelevant in the end because we do not have reliable wind data for any reasonable DZ during any reasonable jump time. There are winds for Portland. Winds for Toledo. Winds for Seattle. Winds for Salem.
But there is no wind data for Ariel, Battle Ground, Orchards, Hockinson, Brush Prairie, or Vancouver during the time period of 8:10 to say 8:20. It's all extrapolation and estimation.
My point is that, if we can gain anything from this weather/wind data, it is that our understanding of the winds is incomplete and far more variable than simply "blowing directly northeast". All that said, I am working on a tip from a source about information that may indicate definitely what the wind was like that night in those areas I indicated above. Once I verify its accuracy, I will post what I find.
Chaucer, I presume the "Aviation Weather Reports" that you mention are the routine Hourly Sequence Reports from various ground stations. These hourly sequence reports include the measured ground data such as winds at that station, the atmospheric pressure, the estimated height of cloud layers and their coverage, the estimated visibility, and any comments that are applicable about recent or predicted future weather events for that station. The sequence reports do not include winds aloft.
Twice a day, the FAA issues predicted winds aloft based on data produced by the National Weather Service. These predictions are used by pilots in their flight planning. The winds aloft are based, at least in part, on the balloon data provided by the NOAA, and that in turn is generated from actual measured balloon data.
Pilot reports can include such things as cloud heights, and depending on the aircraft's equipment, may be able to provide winds aloft speeds and directions. In 1971, this would usually require the pilot to do some calculations.
The information that the FAA provided to the FBI for predicted jump zones was, at best, just estimates. And of course, no one knows exactly where Cooper jumped.
The NOAA measured data for the date of the hijacking was determined independently by Eric Ulis and myself. We applied that data to refine the Western Flight Path. It appears that only the people who have never seen this data are the ones who claim that it is invalid.
Chaucer, let me say again that you and anyone else that you are talking to would greatly benefit from reading the FAA publication "Aviation Weather". Otherwise, you are just going with "Old Wives Tales".