Although extremely rare, auroras are occasionally seen in Southern California. I can recall a time when I saw the red glow in the northern sky from Palos Verdes Peninsula.
A space probe called Advanced Composition Explorer (ACE), measures attributes of the solar wind. ACE is useful to forecast (short term – an hour or so) fluctuations in the solar wind that may cause power-grid outages and extraordinary auroras under the right conditions. SpaceWeather.com points out that there are no plans to replace this resource when it ceases to function. From SpaceWeather.com:
COMMENTS, PLEASE: NASA’s ACE spacecraft is almost four years past its intended lifetime. Although ACE measurements of the solar wind flowing past Earth are crucial to space weather forecasts, there is no plan to replace ACE when the craft ceases to function. NOAA is seeking public comment on this state of affairs. If you enjoy auroras, please let them know that ACE needs a successor.
The ACE Caltech Website has this additional information about ACE:
From a vantage point approximately 1/100 of the distance from the Earth to the Sun ACE performs measurements over a wide range of energy and nuclear mass, under all solar wind flow conditions and during both large and small particle events including solar flares. ACE provides near-real-time solar wind information over short time periods. When reporting space weather ACE can provide an advance warning (about one hour) of geomagnetic storms that can overload power grids, disrupt communications on Earth, and present a hazard to astronauts.
ACE orbits the [Lagrange] L1 libration point which is a point of Earth-Sun gravitational equilibrium about 1.5 million km from Earth and 148.5 million km from the Sun. With a semi-major axis of approximately 200,000 km the elliptical orbit affords ACE a prime view of the Sun and the galactic regions beyond. The spacecraft has enough propellant on board to maintain an orbit at L1 until ~2019.