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): 4
| Planetary K-index (Kp):
Solar Wind: 444 km/s at 1.0 protons/cm3, Bz is -4.0 nT
(May 28, 2023 at 1946 UT)
X-ray Solar Flares:
6h hi [M1.0][1021Z 05/28] 24h hi [M1.0][1021Z 05/28]
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: 15 - 21 May 2023
Solar activity varied from low to high levels. Region 3310 (S20, L=284, class/area=Cko/320 on 19 May) produced the strongest flare of the period, an M9.6 (R2-Moderate) flare at 16/1643 UTC before it fully rotated on to the visible disk from the SE limb. Of the 23 M-class flares (R1-R2 Minor-Moderate) recorded during the period, Region 3311 (N18, L=271, class/area=Ekc/420) was responsible for 21 of them, the largest of which was an M8.9 (R2) flare at 20/1235 UTC. Although the region was the most magnetically complex of the 18 numbered active regions observed on the visible disk during the reporting period, it was in a decaying trend by 21 May.
Other activity included Type II radio sweeps at 16/1731 UTC and 17/1522 UTC, two Tenflares on 20 May, and a filament eruption along side a CME-producing C4.3/Sf flare at 17/1530 UTC from Region 3309 (S18, L=052, class/area=Cro/020). The subsequent CME signatures in coronagraph were analyzed and modeled with anticipated effects at Earth suggested late on 21 May.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit was mostly at background to moderate levels over the reporting period.
Geomagnetic field activity ranged from quiet to G2 (Moderate) geomagnetic storm levels. Quiet to unsettled levels were observed on 15-16 May and decreased to only quiet levels until of late on 19 May. Active levels were observed during the last synoptic period of 19 May and increased to G2 (Moderate) geomagnetic storm levels early on 20 May. Total magnetic field strength increased to a peak of 21 nT and Bz reached as far south as -17 nT during what appeared to be a CIR, with possible embedded transient, ahead of a negative polarity CH HSS. Bz was persistently southward during the first half 20 May but rotated northward just before midday. With the northward rotation, geomagnetic activity decreased to unsettled to active conditions. On 21 May, another enhancement in the solar wind from an expected CME that left the Sun on 17 May was observed which again resulted in G2 (Moderate) geomagnetic storm levels through the end of the reporting period. With the second enhancement, solar wind speeds increased to between 500-600 km/s and total magnetic field strength briefly reached 13 nT, while the Bz component was observed as far south as -10 nt.
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
22 May - 17 June 2023
Solar activity is expected to be at moderate to high, with a chance for very high, though 30 May, until Region 3311 rotates around the western limb or decays sufficiently to lower its flare potential. Low to moderate solar activity is expected for the remainder of the outlook period.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be high levels from 22 May - 02 Jun in response to recently elevated geomagnetic activity followed by enhanced solar wind from coronal hole influence over the next 6 days. Flux levels are likely to return to moderate levels from 03-17 Jun.
Geomagnetic field activity is expected to range from quiet to G1 (Minor) geomagnetic storm levels. G1 conditions are likely on 22 May due to persistent transient influence and 23-24 May in response to negative polarity coronal hole influence. Active conditions are anticipated on 02 Jun and 16 Jun with unsettled conditions likely on 25-26 May, 03-05 Jun, and 17 Jun due to multiple recurrent coronal holes. The remainder of the outlook period is likely 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, 2022, Tomas David Hood (NW7US), all rights reserved.
No part, except for the space weather 'banners', may be copied without express permission.