Current sunspot cycle activity, space weather, solar storm and geomagnetic conditions and radio propagation forecasts

Current sunspot cycle activity, space weather, solar storm and geomagnetic conditions and radio propagation forecasts

This page was rendered on 12-Jul-21 1214 UTC.
This page was first created in 1998, by Tomas David Hood (NW7US)

Current Sunspot Cycle 24 Activity and Space Weather

Sun Spots: 23 as of 07/11/2021 :: 10.7-cm Flux: 74 SFU
(SFU=Solar Flux Units)

Space Weather Overview Graphic from SWPC

30 Minutes of Dazzling Sun! Ultra-high Definition 4k View

An Intimate View of the Sun, Every Day of 2015 (Year 6 of SDO) UHD 4k

Watch Five Very Intense X-class X-ray Flares Erupt, Back-to-back!
(From the largest sunspot region in 20+ years…)

Check out the X2.7 X-ray Flare (May 5 2015) – ‘Biggest’ of 2015, so far

See highlights of the last five years of the Sun, as seen by SDO

Planetary A-index (Ap): 4 | Planetary K-index (Kp): 1
Solar Wind: 411 km/s at 4.0 protons/cm3, Bz is 0.0 nT
(May 05, 2021 at 0435 UT)

X-ray Solar Flares:
6h hi [B7.1][0125Z 07/11] 24h hi [B7.1][0125Z 07/11]

Background X-ray Level, Last Six Days


Check out the current Aurora Oval and activity.

What is the difference between the CB and Amateur Radio Services, in the USA? Here are some thoughts on the portrayal of the Amateur Radio Service by the Hit TV Series, NCIS, and a clarification of the difference between CB radio and ham radio.
(Skip to timecode 1:33 to bypass the introductory chat and talk about the headset microphone.)

Here is a video introduction to shortwave / HF amateur radio — what is it that we amateur radio oprators listen to? If you have not yet been introduced to this world, this is a very basic introduction.

If you are using software utilities such as Ace-HF, that require a “smoothed” sunspot number
(Referred to as the SSN), or, the smoothed 10.7-cm Radio Flux Index,
use the following predicted values in this following table:

Predicted SMOOTHED Sunspot Number And Radio Flux Values
With Expected Ranges


Smoothed Sunspot Number

Smoothed 10.7 cm Radio Flux

To understand more about the Maximum Usable Frequencies, and related
science, please read the MUF Basics Page.

Global HF Propagation Conditions
Global HF Propagation Conditions for 0400Z on 05 May, 2021
High Latitude: Normal
Middle Latitude: Normal
Low Latitude: Normal

Geomagnetic Latitude Ranges:
High: 60-90 degrees
Middle: 20-60 degrees
Low: 0-20 degrees

At 0805 UTC, on 9 August 2011, a strong magnitude X6.9 X-ray flare — the strongest yet in this current solar cycle (Cycle 24) — erupted on the northwestern solar limb. Here is a HD Movie of the event:

Videos of Interest – Space Weather, Solar Dynamics Observatory, STEREO, and more… from the NW7US YouTube Channel. (Click on the small image to launch the video…)

The NW7US Current Sunspot and Geophysical Activity Report
The observations, prognastications, and comments by NW7US
NW7US is Tomas David Hood, Propagation and Space Weather Columnist
for CQ Communications

More about Background X-rays

The hard X-ray energy present from the wavelengths of 1 to 8 Angstroms provide the most effective ionizing energy throughout all of the ionospheric layers in our atmosphere. The GEOS satellites measure these wavelengths and the resulting measurements are reported as the “background X-ray level” throughout the day. A daily average is reported, as well.

Just like X-ray flares, the background hard X-ray level is measured in watts per square meter (W/m2), reported using the categories, A, B, C, M, and X. These letters are multipliers; each class has a peak flux ten times greater than the preceding one. Within a class there is a linear scale from 1 to 9.

If one records the daily background X-ray levels for the course of a sunspot cycle, one would discover that the background X-ray levels remained at the A class level during the sunspot cycle minumum. During the rise and fall of a solar cycle, the background X-ray energy levels remained mostly in the B range. During peak solar cycle periods, the background energy reached the C and sometimes even M levels.

Armed with this information, can we discover any clues as to the current status of Sunspot Cycle 24? Below is a graph plotting the background hard X-ray energy reported by the GEOS satellites since the end of Sunspot Cycle 22. Clearly, we see a noticeable rise in Cycle 24 activity. We’re seeing the energy mostly in the B level more often, supporting the view that Cycle 24 is alive and moving along toward an eventual sunspot cycle peak in several years.

Overall, the monthly average background ‘hard’ X-ray level is rising (as seen by the following plot), showing a change from deep solar cycle minimum. We are certainly in the rising phase of Sunspot Cycle 24. While it has been a slow up-tick over the last eighteen months, I expect to see a more rapid rise during mid to late 2011.

Background X-ray (1 to 8 Angstrom) Plot

Highlights of Solar and Geomagnetic Activity
Covering the period: 28 June – 04 July 2021

Solar activity ranged from very low to high levels. Region 2838 (N24W88, class/area Cro/030 on 03 Jul) rapidly emerged near the NW limb on 03 Jul. It produced the strongest event of the period, an impulsive X1/Sn flare (R3 – Strong) at 03/1429 UTC. Associated with the event was a Type II radio sweep (357 km/s) along with low-level radio bursts across several different frequencies. Subsequent coronagraph imagery from SOHO LASCO/C2 showed several different westward CME signatures. Analysis determined all to be oriented away from the Sun-Earth line. The region also produced an M2/Sf flare (R1 – Minor) at 03/0717 UTC, an M1/Sf flare (R1) at 03/1702 UTC and a final M1/Sf flare (R1) at 04/0509 UTC as the region rotated behind the NW limb.

The largest region on the visible disk was Region 2835 (S18W16, class/area Ekc/770 on 01 Jul). The largest flare it produced during the reporting period was a C3 at 30/1815 UTC. The growth of Region 2835 peaked on 01 Jul and has been in gradual decay in the days since. The three remaining numbered active regions were relatively simple and stable or in decay.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels throughout the summary period.

Geomagnetic field activity varied from quiet to active levels. Late on 30 Jun, a relatively gradual increase in solar wind parameters was observed which was likely from transient influence of a CME that left the Sun on 27 Jun. Solar wind speeds increased from the mid 300 km/s to a peak of just over 500 km/s. Total magnetic field strength (Bt) increased to a brief peak of 13 nt early on 01 Jul. Bz reached a maximum southward flux of -9 nT. The following geomagnetic field response was mostly unsettled to active through the later part of 30 Jun. A decline in Bt early on 01 Jul resulted in quiet conditions despite wind speeds being elevated through 03 Jul. The remainder of the summary period was quiet.

Monthly and smoothed sunspot number – The monthly mean sunspot number (blue) and 13-month smoothed monthly sunspot number (red) for the last five cycles. You can see that this current cycle, Cycle 24, is a weak cycle, compared to the last few.

(Click to see actual size)
Monthly and smoothed sunspot number chart

Daily and monthly sunspot number (last 13 years)

Daily sunspot number (yellow), monthly mean sunspot number (blue), smoothed monthly sunspot number (red) for the last 13 years and 12-month ahead predictions of the monthly smoothed sunspot number:

SC (red dots) : prediction method based on an interpolation of Waldmeier’s standard curves; It is only based on the sunspot number series.

CM (red dashes) : method (from K. Denkmayr and P. Cugnon) combining a regression technique applied to the sunspot number series with the aa geomagnetic index used as a precursor (improved predictions during the minimum phase between solar cycles).

(Click to see actual size)
Daily and monthly sunspot number (last 13 years)

What is ‘Space Weather’? Click on these two information slides to view them in full size:

What is Space Weather? Slide 1 of 2 What is Space Weather? Slide 2 of 2

View of numbered sunspot regions and plages (if any)
(Click for large view)

Active Regions and Plages

Active sunspot regions, and plages, identified by SIDC

SIDC Solar Disc with active regions and plages


STEREO Behind Image
What is coming
SOHO EIT 195 Image
Current View
STEREO Ahead Image
What was…

Real Time Solor Wind and Aurora:

On 2021 Jul 12 1207Z: Bz: 2.8 nT
Bx: 6.7 nT | By: -2.2 nT | Total: 7.6 nT
Most recent satellite polar pass:
Centered on // : UTC
Aurora Activity Level was at UTC
visit noaa for latest.

This is a video of the simulation from May 27-28, 2011, showing
the Geomagnetic disturbance caused by the solar wind

Three Day Forecast of Solar and Geomagnetic Activity
(as of 2200Z on 07 Dec 2014)

Solar Forecast:

Solar activity is expected to be low with a chance for M-class flares on days one, two, and three (08 Dec, 09 Dec, 10 Dec).

Geomagnetic Forecast:

The geomagnetic field is expected to be at quiet to minor storm levels on day one (08 Dec), quiet to active levels on day two (09 Dec) and quiet levels on day three (10 Dec).

Forecast of Solar and Geomagnetic Activity
05 July – 31 July 2021

Solar activity is expected to be very low to low over the outlook period. There is potential for Region 2838 (N24, L=100), which produced an X1/Sn flare at 03/1429 UTC as it rotated around the NW limb, to increase flare probabilities after 16 Jul if it maintains around the farside and rotates back onto the visible disk.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to range from normal to high levels. High levels are likely on 12-14 Jul and 20-23 Jul in response to CH HSS activity. The remainder of the outlook period is likely to be at normal to moderate levels.

Geomagnetic field activity is expected to be at quiet to active levels. Active levels are likely on 10 Jul and 18-19 Jul; unsettled levels are likely on 05-06 Jul, 11 Jul and 20 Jul. All elevated levels on geomagnetic activity are in response to multiple, recurrent CH HSSs. The remainder of the outlook period is expected to be at quiet levels.

Real-time foF2 map from IPS (Ionospheric Prediction Service), Australian Space Weather Agency

foF2 Map from IPS, Australia

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