DX Aid is a program by Peter Oldfield which allows you to visualize areas of daylight and darkness on an azimuthal equidistant projection of your choosing.  In the plots below, darkness is enclosed in the dark blue area and daylight is in the lighter area with the sun's location indicated as the yellow circle.  Target locations are indicated by the white crosshair.  Please click on the QSO of interest and then hit the "Back" button on your Web browser to return to the index page. Hopefully you can see the similar pattern to these...especially the sunrise QSO's which are from 3 different areas of the USA (Washington, Colorado and North Carolina). Signal azimuths are amazingly consistent and independent of the target location. This is also characteristic of 80 meter long path propagation which is much more common than on 160.

Local USA sunrise long path 160M QSO's at ~210 degrees true:

W0ZV to UA9UCO...29 September 1987

W0ZV to JJ1VKL/4S7...28 December 1991

N7UA to A61AJ...26 November 2000

W4ZV to 3W5FM...6 January 2000

W4ZV to XZ0A...21 January 2000

W4ZV to XU7ACB...5 December 2001

N7UA to 5B4ADA and EU...16 December 2001

W4ZV to JT1CO...3 February 2003

W4ZV to HS72B...3 December 2004

Also see the "Pacific Coast Salty Dog Antenna Test" at the Force 12 Website...interesting story about 75/80M long path from the West Coast..."Each 2 element parasitic array is aimed exactly at 210 degrees (true, not magnetic).  Thanks to perhaps the most knowledgeable person on this path, Bob, W6RJ for verifying this exact direction for the majority of long path openings." (Bob uses a rotary Yagi on 75/80)  See the great 75M long path opening they described here:

N6BT to OH5BR...23 December 2000

Local USA sunset long path 160M QSO's at ~150 degrees true:

W4ZV to 9V1XQ...13 January 1996

W4ZV to S21XX...4 February 1997

KL7Y to ZS4TX...2 January 1997 (reported 90-120 degrees)

Skew away from auroral zones during geomagnetic disturbances is an entirely different phenomena in my opinion.  This has been well documented in this CQ Magazine article by Carl K9LA.  Here's an example for a different path than that described in Carl's article:

N5TW to VK3...26 September 2001