= NOW 18 WPM transition file follows =

Again this week sunspot numbers and solar flux were higher than the
week before.  Average daily sunspot numbers more than doubled, from
70.6 to 146.9, and average daily solar flux increased from 141 to
164.5. Both figures represent a substantial increase in solar
activity.  Planetary A index averages went from 7.6 to 8.1, while
middle latitude A index advanced from 6.4 to 7.3.  Three new sunspot
groups emerged on April 13, one more on April 16, and another on
April 17.  Predicted solar flux over the next few weeks is 145, 140
and 135 on April 21 to 23, 130 on April 24 and 25, 125 on April 26
and 27, 160 on April 28 and 29, 165 on April 30, 172 on May 1 to 3,
170 on May 4, 172 on May 5 to 7, 178 on May 8, 182 on May 9 to 12,
then 175, 178 and 170 on May 13 to 15, 168 on May 16 and 17, 175 on
May 18, then 172 on May 19 to 21, then 168 and 162 on May 22 and 23,
160 on May 24 to 26, 165 on May 27, and 172 on May 28 to 30.
Predicted planetary A index is 20, 16, 12 and 8 on April 21 to 24, 5
on April 25 to 27, 15 on April 28 to 30, then 12 and 10 on May 1 and
2, 8 on May 3 and 4, 5 on May 5 and 6, 12 on May 7, 5 on May 8 to
10, then 8 on May 11 and 12, 5 on May 13 to 18, then 10, 8, 5 and 5
on May 19 to 22, 15 and 18 on May 23 and 24, 15 on May 25 to 27,
then 12 and 10 on May 28 and 29.  Weekly Commentary on the Sun, the
Magnetosphere, and the Earths Ionosphere, April 20, 2023, from
OK1HH.  Of the fifteen sunspot groups observed over the past week,
AR3272 and AR3282 were the source of most of the flares. Both had a
beta gamma magnitude configuration. 61 C class flares and 4 M class
flares were observed.  The partial halo CMEs on 15 and 16 April were
the source of particles that reached Earth on 18 April, when the
solar wind speed increased abruptly at 1308 UTC and a geomagnetic
disturbance developed.  A positive phase of the ionospheric
disturbance was recorded on the afternoon of 18 April, followed by a
negative phase on 19 April.  This was followed on 20 April with a
significant increase in f0F2 and improved shortwave propagation
conditions before noon UTC.  The outlook looks promising for the
first half of May, when solar activity should increase further.  Dan
Handa, W7WA commented on the news last week about the current solar
cycle reaching a peak earlier than predicted, perhaps by the end of
this year.  I told him I hoped it would not peak early, because I
wanted to see several more years of increasing activity.  Dan sent a
very detailed graph of Solar Cycle 19 from 1954 to 1966, and wrote,
I have read, and more than once, a slow rise means a low sunspot
max. The previous Solar Cycle 24 took five years to reach a
relatively low maximum. A rapid increase can mean a high sunspot
maximum. The granddaddy of our lifetime, Solar Cycle 19 peaked in
three years.  There was a lot of short term variation in the Solar
Cycle 19 sunspot number, just like were seeing now. From the graph
the timing of the Solar Cycle 19 peak can be defined three different
ways, the daily peak, the smoothed monthly peak or the smoothed
yearly peak, take your pick.  Another Solar Cycle 19? Many hams have
dreamed of this for the past six decades.  I sent Dale links to some
recent images from Spaceweather.com.  They can be found at,
//www.spaceweather.com/images2023/ .  I hope this clears up the
confusion.  A story about a possible early Solar peak is available
at, //www.space.com/ .  Sunspot numbers were 154, 153, 151, 155,
162, 140, and 113, with a mean of 146.9. 10.7 cm flux was 159.5,
171.3, 175.8, 177.8, 166.6, 153.2, and 147, with a mean of 164.5.
Estimated planetary A indices were 6, 7, 9, 4, 6, 13, and 12, with a
mean of 8.1. Middle latitude A index was 5, 10, 8, 4, 6, 9, and 9,
with a mean of 7.3.

= END OF 18 WPM transition file <