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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This page was rendered on 17-May-22 0431 UTC.
This page was first created as HFRadio.org in the mid 1990s, and morphed here in 1998, by Tomas David Hood (NW7US)
Current Sunspot Cycle 25 Activity ~ Space Weather ~ Shortwave Radio Propagation
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): 10
| Planetary K-index (Kp): 1
Solar Wind: 469 km/s at 13.0 protons/cm3, Bz is -1.0 nT
(May 17, 2022 at 0420 UT)
X-ray Solar Flares:
6h hi [M2.4][1310Z 05/16] 24h hi [M2.4][1310Z 05/16]
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
YR/MO
Smoothed Sunspot Number
Predicted/High/Low
Smoothed 10.7 cm Radio Flux
Predicted/High/Low
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
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: On How NCIS TV Show Maligned Amateur Radio Service (Full UHD Version)
What's the difference between CB and amateur (ham) radio?
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: 09 - 15 May 2022
Solar activity ranged from low to high levels. Region 3006 (S30, L=235, class/area=Eai/180 on 10 May) produced the strongest event of the period, an impulsive X1/1b at 10/1355 UTC. Type II and Type IV radio sweeps occurred near the event but wasn't clear if it was associated with activity near the E limb, which also produced an associated CME around the same time. The region only produced C-class activity after that event and slowly decayed over the next several days. Region 3007 (S24, L=184, class/area=Ekc/350 on 12 May) produced an M1/1n flare on 11/1648 UTC. While being the most complex region on the visible disk, it also only produced C-class activity through the end of the reporting period. The remaining spotted regions on the visible disk were relatively simple and produced only low-level X-ray activity.
Other activity included several M-flare events that were produced from activity from around both the E and W limbs. An M2 flare at 11/1858 UTC from the vicinity of Region 3004 (S16, L=324, class/area=Dkc/500 on 05 May), which had around the W limb two days before, produced a Type II and Type IV radio sweep. Ejecta from the several CMEs observed during the period were determined to be off the Sun-Earth line, with only the periphery of some of the CMEs having the potential to cause minor enhancements near Earth.
No proton events above S1 (Minor) were observed at geosynchronous orbit. An enhancement below the S1 threshold was observed after the M2 flare from old Region 3004 around the W limb. The maximum >10 MeV proton flux was 5 pfu, observed early on 12 May.
The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels throughout the reporting period.
Geomagnetic field activity ranged from quiet to active conditions. Unsettled conditions that were observed on 09 May and 13 May were likely associated with weak enhancements from transient activity. Unsettled conditions on 14 May into active conditions on 15 May were associated with the onset CIR followed by influence from a positive polarity CH HSS. Solar wind speeds increased from the mid 300's km/s to ~570 km/s on 15 May. The remainder of the reporting period was at quiet levels.
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:
View of numbered sunspot regions and plages (if any)
Source: http://www.solarmonitor.org/.
(Click for large view)
Active sunspot regions, and plages, identified by SIDC
STEREO IMAGES
What is coming
Current View
What was...
Real Time Solor Wind and Aurora:
On 2022 May 17 0426Z: Bz: 1.0 nT
Bx: -3.4 nT | By: 6.7 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
Outlook: (valid from 1230UT, 16 May 2022 until 18 May 2022)
16 May 2022 10.7-cm Flux: 153 / Ap: 011
17 May 2022 10.7-cm Flux: 152 / Ap: 005
18 May 2022 10.7-cm Flux: 150 / Ap: 002
Forecast:
Solar Flares: C-class flares expected, (probability >=50%) Geo-Disturbance: Quiet (A<20 and K<4) Solar Proton Event: Quiet
Comment from the SIDC (RWC Belgium): Solar flaring activity was low but frequent during the last 24 hours, with seven C-class flares detected and the strongest being a C5 today at 10:01 UT. NOAA Active Region (AR) 3015 produced three of the C-class flares, while the brightest flare was produced by an AR yet to turn into view, at N17E84. Another AR not yet visible from Earth's direction produced a C1 flare at S16E89 today at 05:01. NOAA AR 2015 and the two unnumbered AR are expected to produce more C-class activity in the next 24 hours. As the magnetic configuration of the two AR cannot be determined, there is a fair chance of an isolated M-class flare from any of those two AR during the coming 24 hours.
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
16 May - 11 June 2022
Solar activity is expected to be low levels throughout most of the outlook period. With the exception of 21-22 May, regions associated with M-flare activity are expected to be present on the visible disk, carrying with them a slight chance for M-class activity.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at moderate levels from 16-25 May and 05-11 Jun. High levels are expected on 26 May - 04 Jun and are associated with influence from anticipated CH HSS activity.
Geomagnetic field activity is expected to be at quiet to G1 (Minor) geomagnetic storm levels. G1 levels are likely on 24 May; active levels are likely on 16 May, 25-17 May, and 11 Jun; unsettled levels are likely on 17 May, 19-20 May, 28 May, and 10 Jun. All elevations in geomagnetic activity are anticipated in response to multiple, recurrent CH HSSs. The remainder of the outlook period is expected to be at mostly quiet levels.
Data and images courtesy of IPS Australia, NOAA, NASA, SWPC, SIDC
Layout, analysis, commentary, and certain forecasts and content is Copyright, 2021, Tomas David Hood (NW7US), all rights reserved.
No part, except for the space weather 'banners', may be copied without express permission.