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.
This website is kept alive by Tomas (NW7US), out of "spare change" (which there's not always enough of), and, by the kind, helpful people who visit this website. Would you like to help me keep this site running 24/7? If you are able to help me keep this website up and running, please: help me keep this site running for everyone... click on this donation button:
There are other ways that you can help me keep this site up and running. Here are a few other ways:
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): 3
| Planetary K-index (Kp):
Solar Wind: 320 km/s at 2.0 protons/cm3, Bz is -4.0 nT
(Feb 24, 2024 at 0831 UT)
X-ray Solar Flares:
6h hi [M4.5][0621Z 02/24] 24h hi [M4.5][0621Z 02/24]
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
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: 12 - 18 February 2024
Solar activity reached high levels on 12 and 16 Feb, and moderate levels on 14-15 Feb. The largest event of the period was an X2.5/1n flare at 16/0653 UTC from Region 3576 (S16, L=060, class/area=Fkc/660 on 14 Feb). Region 3576 was the largest and most active sunspot region of the period, and in addition to the X-flare, produced eight M-class flares throughout the week. Region 3582 (N06, L=035, class/area=Dai/240 on 13 Feb) produced an isolated M1 flare at 14/0310 UTC. No Earth-directed CMEs were observed this period.
The greater than 10 MeV proton flux reached S2 (Moderate) levels on 12-13 Feb, and S1 levels on 14 Feb, following a C6.9 flare at 12/0554 UTC from Region 3576. A peak flux of 118 pfu was observed at 13/0615 UTC. The greater than 10 MeV proton flux was elevated above background levels over 15-18 Feb, but remained below event thresholds.
The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels throughout the week.
Geomagnetic field activity was quiet on 12 Feb. Active levels were observed on 13 Feb, and unsettled levels were observed on 14 Feb, due to the arrival of multiple CMEs from 10-11 Feb. Quiet conditions were observed over 15-17 Feb, and quiet to unsettled conditions were observed on 18 Feb.
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:
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
19 February - 16 March 2024
Solar activity is expected to be low with a varying chance for M-class flare activity throughout the period. Old Region 3575 (S37, L=177), which produced M-class flares last rotation and multiple CMEs during its transit of the far-side, is expected to return to the visible disk on 20 Feb.
No proton events are expected at geosynchronous orbit, barring significant flare activity.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at normal to moderate levels throughout the outlook period.
Geomagnetic field activity is expected to be mostly quiet throughout the outlook period. Unsettled conditions are likely on 19-20 Feb due to the anticipated arrival of a CME from 16 Feb, and again on 26-27 Feb due to negative polarity CH HSS influences.
Data and images courtesy of IPS Australia, NOAA, NASA, SWPC, SIDC
Layout, analysis, commentary, and certain forecasts and content is Copyright, 2022, Tomas David Hood (NW7US), all rights reserved.
No part, except for the space weather 'banners', may be copied without express permission.