4.67 Kp index 39 ap index
G1 Minor Geomagnetic Storm
PLANETARY INDICES
High Latitude Aurora Viewing Possible
Est. daily 15 Ap index
G1 Geomagnetic Storm
RADIO AURORA ACTIVE
High Latitude Radio Aurora
50-144 MHz Possible
The higher the 3-hourly Kp index (0-9) the greater the chance of seeing the Aurora Borealis. The data are collected from ground-based magnetometers at 13 mid-latitude observatories (only 8 in this case). The scale is non-linear.
The ap index (0-400) is the equivalent 3-hourly range: the amplitude on a linear scale.
This Ap index estimate is the rolling average of the last eight ap indices: the true Ap index is the same average for the UT day. High Kp, ap & Ap indices (caused by strong solar activity) may indicate enhanced VHF radio communication (28-433 MHz) at a range of 1000 miles or more in mid- to high latitudes: the radio-aurora.