Check out the ACE-HF propagation software - the latest is version 2.05. ACE-HF is propagation forecasting and modeling for Amateur Radio as well as for Shortwave radio Listening and general HF operation. This software is even used by the military and other clients around the world. This software is developed and maintained by the same engineers that keep VOACAP up-to-date. As a result, this software is the most accurate user interface integrated with VOACAP. CHECK IT OUT, TODAY. This software is the most accurate modeling software available, and is endorsed by NW7US. Read the details to find out why.
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Map, Above: Conditions in the D region of the ionosphere have a dramatic effect on high frequency (HF) communications and low frequency (LF) navigation systems. The global D Region Absorption Predictions (D-RAP) depicts the D region at high latitudes where it is driven by particles as well as low latitudes, where photons cause the prompt changes.
Note: At times, images may appear broken or missing, when SDO is working on the AIA/HMI instruments.
Planetary A-index (Ap): 22
| Planetary K-index (Kp): 3
Solar Wind: 588 km/s at 7.0 protons/cm3, Bz is -1.0 nT
(Aug 21, 2017 at 0943 UT)
X-ray Solar Flares:
6h hi [M1.1][0136Z 08/20] 24h hi [M1.1][0136Z 08/20]
Background X-ray Level, Last Six Days
Aug 20 2017 :: B3.3
Aug 19 2017 :: B3.3
Aug 18 2017 :: B1.3
Aug 17 2017 :: A8.3
Aug 16 2017 :: B1.3
Aug 15 2017 :: B1.0
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
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...)
Video: Voyager Finds Magnetic Foam at Solar Systems Edge
Video: Zoom View of Prominence Eruption and X-Ray Flare - M2.5 Magnitude - June 7 2011
Video: X-Ray Flare, Coronal Mass Ejection, Proton Storm - M2.5 Magnitude - June 7 2011 (Close-up of the video, above)
Video: Stunning Close-up View of M3 X-Ray Flare 24 February 2011
Video: June 2011 20-meter (14-Mhz) JT65A Coverage Map of NW7US Radio Signal
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.
Highlights of Solar and Geomagnetic Activity
Covering the period: 07 - 13 August 2017
Solar activity was very low. Region 2670 (S05, L=119, class/area Cso/160 on 02 Aug) continued it transit across the visible disk during the period as a simple Hsx/alpha spot group with no flaring activity observed. No Earth-directed coronal mass ejections were observed.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels from 07-11 Aug with a peak flux of 11,301 pfu observed at 07/1440 UTC. Electron flux values decreased to normal to moderate levels on 12-13 Aug due to the arrival of a negative polarity coronal hole high speed stream (CH HSS).
Geomagnetic field activity ranged from quiet to unsettled levels during the period. Solar wind speed was in decline at the beginning of the period from a waning positive polarity CH HSS. Solar wind speeds declined from near 570 km/s early in the period to nominal levels by late on 08 Aug. Total field ranged from 2-6 nT through 10 Aug. On 11 Aug, total field and solar wind began to increase as a negative polarity CH HSS became geoeffective. Total field increased to a maximum of 12 nT at 12/0135 UTC while solar wind increased to around 650 km/s by 13/1750 UTC. The geomagnetic field responded with quiet levels from 07-10 Aug and quiet to unsettled levels from 11-12 Aug. Geomagnetic activity decreased to quiet levels again on 13 Aug.
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)
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)
What is 'Space Weather'? Click on these two information slides to view them in full size:
Active sunspot regions, and plages, identified by SIDC
Latest GOES 15 Image of the Sun
What is coming
Real Time Solor Wind and Aurora:
On 2017 Aug 21 0950Z: Bz: 0.2 nT
Bx: -3.5 nT | By: -0.3 nT | Total: 3.5 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
Outlook: (valid from 1230UT, 20 Aug 2017 until 22 Aug 2017)
20 Aug 2017 10.7-cm Flux: 087 / Ap: 024
21 Aug 2017 10.7-cm Flux: 090 / Ap: 007
22 Aug 2017 10.7-cm Flux: 094 / Ap: 007
Solar Flares: M-class flares expected (probability >=50%) Geo-Disturbance: Active conditions expected (A>=20 or K=4) Solar Proton Event: Quiet
Comment from the SIDC (RWC Belgium): NOAA AR 2671 continued producing C-class flares, whereas the region rotating into view produced an M1.1 flare peaking at 01:52 UT. More M-class flaring (and possibly X) can be expected.
Three Day Forecast of Solar and Geomagnetic Activity
(as of 2200Z on 07 Dec 2014)
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).
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
14 August - 09 September 2017
Solar activity is expected to be at very low levels. A chance for C-class flare activity is possible from 14-28 Aug as a new active region rotates across the visible disk.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels from 14-16, 18-30 Aug and again from 01-07 Sep due to CH HSS influence. Normal to moderate levels are expected on 17, 31 Aug and again on 08-09 Sep.
Geomagnetic field activity is expected to be reach unsettled to active levels on 14, 16-22, 30-31 Aug and from 01-02 and 08-09 Sep with G1 (Minor) geomagnetic storm levels are likely on 17-18 and 31 Aug due to recurrent CH HSS activity.
Be sure to check the Date shown in each photo - is it today's date?
(click to enlarge)
Check out these books on Radio Propagation:
+ The New Shortwave Propagation Handbook (Paperback) - by George Jacobs, Theodore J. Cohen, R. B. Rose. The NEW Shortwave Progagation Handbook may well be the only book you'll need on the subject of ionospheric propagation! It is a "must read" for Radio Amateurs, Shortwave Listeners, and radio communicators of any type who need to make the most productive use of the radio spectrum, regardless of the time of day, the season of the year, or the state of the sunspot cycle. It will become your ever-present companion a the operating table as you master the art of shortwave radio progagation.
+ How Radio Signals Work (Paperback) - by Jim Sinclair. This book provides a basic understanding of the way radio signals work-without becoming bogged down with the technicalities. It covers all kinds of radio signal types--including mobile communications, short-wave, satellite, and microwave. No detailed knowledge of electronics or mathematics is required. A-Z coverage of radio signals including satellites, mobile communications, and short-wave radio. No math or electronics background necessary.
+ Introduction to RF Propagation (Hardcover) - by John S. Seybold. This book provides readers with a solid understanding of the concepts involved in the propagation of electromagnetic waves and of the commonly used modeling techniques. While many books cover RF propagation, most are geared to cellular telephone systems and, therefore, are limited in scope. This title is comprehensive-it treats the growing number of wireless applications that range well beyond the mobile telecommunications industry, including radar and satellite communications.
Data and images courtesy of IPS Australia, NOAA, NASA, SWPC, SIDC
Layout, analysis, commentary, and certain forecasts and content is Copyright, 2017, Tomas David Hood (NW7US), all rights reserved.
No part, except for the space weather 'banners', may be copied without express permission.