Spaceweather.com reports a Cannibal Coronal Mass Ejection on April 15 sparked geomagnetic storms.  On April 16, the storm became severe (G4) with Northern Lights sighted as far south as France.  The storm is subsiding now to a category G1/G2, which could still produce high-latitude auroras.

Although Regions AR4062 and AR4064 have been relatively quiet they are more structurally complex than anticipated.  They will maintain a 60 chance for R1-R2 (Minor-Moderate) flare activity through April 19.  Chances for X-class (Strong) flare activity remain around 10.

Unsettled to active levels are expected on April 18 followed by quiet to unsettled conditions on April 19.

Solar activity is expected to be at moderate to high levels on April 27 to May 10 with the return of Region AR4055.  Low to moderate levels are expected for the remainder of the outlook period. Unsettled to active levels are expected on April 18, April 22 and 23, and on May 3 and 4.

G2 (Moderate) storm levels are expected again on May 2 due to recurrent Coronal Hole High-Speed Stream influences.  G1 (Minor) storm levels are expected on May 1, and May 5 and 6, all due to recurrent Coronal Hole High-Speed Stream activity.

The latest report from Dr. Tamitha Skov, WX6SWW, can be found on YouTube at: https://www.youtube.com/watch?v=zpyPrcMKvTY .

The Predicted Planetary A Index for April 19 to 25 is 10, 8, 8, 15, 15, 15, and 10, with a mean of 11.6.  The Predicted Planetary K Index is 3, 3, 3, 4, 4, 4, and 3, with a mean of 3.4.  10.7 centimeter flux is 145, 145, 150, 155, 155, 160, and 165, with a mean of 153.6.

For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information Service web page at, http://arrl.org/propagation-of-rf-signals.  

For an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere . Information and tutorials on propagation can be found at, http://k9la.us/ .

Also, check "Understanding Solar Indices" from September 2002 QST at https://bit.ly/3Rc8Njt .