A Brief History of
the KH6 Duct into the Pacific Northwest
de Dave, N7DB CN85
The first known station to have heard the KH6HME beacon was Arliss, W7XU, when he lived in Damascus (about 15mi. SE of Portland.) This was once in the earlier part of the '90's.
The next time the KH6 Duct made it into the Northwest, a number of stations actually made contact.
By the middle of the '90's, the Internet was just starting to be used by operators through the use of the "VHF Reflector" via emails. Late in June of 1995 the word got out that WB9AJZ/6 was hearing the KH6HME beacon with his mobile rig around 1900Z down in the SF Bay area.
Note:on this picture, you can make out some of the snow capped peaks here in the Northwest.
Now, the weather condition you should keep in mind is that a HOT thermal low was in the Portland area around this time. Hot Gorge winds and temperatures in the low 100's. The next picture is from the evening. You should still be able to make out the cloud bank along the coast. The picture is at 0300Z (8PM PDT.) Later this evening, N7AVK (now W7EW) worked KH6HME on 2M via the KH6 Duct (0640Z.)
Our third picture is from the next morning around 9AM. By midday, N7AVK was reporting the KH6HME beacon at 10/S9 on 144.170. Note how the cloud bank has moved up the coast from the previous day shot.
Picture number 4 is from the following morning. The Duct was still in play. Operators in the Seattle area had worked KH6HME around midnight (0700Z.) N0XX/7 near Eugene was the only station to work(?) KH6 later this day.
N0XX/7 may have worked KH6HME this afternoon. N7AVK could not hear Paul by this time (2100Z.)
This last picture shows the cloud pattern when the KH6 Duct left us. Note how the cloud bank went to the south and broke up the pattern. You can also see the cooler air coming in from the northwest.
There was at least one other time later in the '90's that the Duct was into the Northwest, but not to the extent as in the summer of '95. Seems like this other time was in August. Similar condition with the thermal low up here, but not as hot.
So, what should one look for? The first tip off will be reports of the KH6 beacon into California. Chances are, we will be experiencing very HOT weather with a thermal low pressure area over us. Probably have hot Gorge winds in the Portland area. The next thing to watch are the VISIBLE weather satellite photos. The cloud banks we are looking for are at low levels and do not show up on the IR and water vapor photos.
The following links should come in handy when the KH6 Duct makes a run into the Northwest.
|NOAA GOES site||www.goes.noaa.gov|
|US Navy weather satellites
|The 2M Propagation Logger||dxworld.com/144prop.html|
Provides info on the KH6HME beacon and other data.
So, please keep a copy of these images as they give you a clue to the way the weather pattern will look in the eastern Pacific when the KH6 Duct makes its way up the Coast. The next time we get KH6 via the Duct, be sure to download the weather satellite images as there is very short time frame that archived images may be available.
de Dave, N7DB CN85