This solution is a bit extreme, but if your planet's solar system is doing something very exotic, you could get just that:
Have the entire solar system travel at relativistic speed through space
You can see some more specific details in this answer for a question of mine (predating worldBuilding.SE so asked on Astronomy.SE) about an even more exotic setup.
Basically, if the entire system is traveling very fast (90% - 99% of the speed of light, or even faster) relative to the galaxy it's passing through, than two separate phenomena create a single bright1, high-radiation circular patch in the sky:
- Light aberration and relativistic beaming means all the starlight reaching the planet is concentrated in a disk 'straight ahead' in the direction of the system's movement (size of disk becomes smaller the faster the system travels). This light is also strongly blue-shifted to a UV, X-ray and Gamma ray level (so radioactive and lethal)
- At those speeds, any interstellar particles the star hits will behave as cosmic rays (I encourage you to read the list of their effects - they are excellent for the epic instant death you need).
So, you have a very exotic planet (which is a good reason to try and build a temporary base on it - for research etc...) - which have a deadly "bright patch" in its night sky. During the day, there will still be insane atmospheric interference, lightning storms, winds etc. But the planet itself shields the base from the worst of the effect. But, a bit before the bright patch rises over the horizon things get much worse, and become instantly lethal when the patch is in the visible night-sky.
1: Note that this "bright patch" will likely not be visible to human eyes - it can be detected by instruments (and by its deadly effect), but with high enough velocity, it won't provide visible light.