4 K_p index  32 a_p index

Minor Geomagnetic Storm

PLANETARY INDICES

High Latitude Aurora Viewing Possible

The higher the Kp index (0-9) the greater the chance of seeing the Aurora Borealis. The three-hourly K-index data are collected from ground-based magnetometers at 13 mid-latitude observatories. The scale is non-linear.
The ap index (0-400) is the equivalent three-hourly range: the amplitude on a linear scale.

This Ap index estimate is the rolling average of the last 8 ap indices: the actual Ap index is the average ap for the UT day. High Kp, ap & Ap indices (as a result of 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.