  Space weather events produce variations in the electric current in the
Earth's magnetosphere and ionosphere. From these high altitude atmospheric
regions, resulting geomagnetically induced currents (GICs) can lead to
fluctuations in ground currents that affect the electric power grid and
potentially overload transformers during extreme storms. The most extreme
geomagnetic storm on record, known as the 1859 Carrington event, was so intense
that ground-based magnetometers were saturated at high magnetic latitudes. The
most reliable, un-saturated observation is the hour-resolution data from the
Colaba Magnetic Observatory in India. However, higher frequency components --
fluctuations at second through minute time cadence -- to the magnetic field can
play a significant role in GIC-related effects. We present a new method for
scaling higher frequency observations to create a realistic Carrington-like
event magnetic field model, using modern magnetometer observations. Using the
magnetic field model and ground conductivity models, we produce an electric
field model. This method can be applied to create similar magnetic and electric
field models for studies of GIC effects on power-grids.
