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 07-Dec-23 1116 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):
Solar Wind: 500 km/s at 2.0 protons/cm3, Bz is 1.0 nT
(Dec 07, 2023 at 1104 UT)
X-ray Solar Flares:
6h hi [M2.3][2126Z 12/06] 24h hi [M2.3][2126Z 12/06]
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: 27 November - 03 December 2023
Solar activity reached high levels on 28 Nov when Region 3500 (S20, L=307, class/area=Dkc/320 on 27 Nov) produced an M3.4 flare (R1/Minor) at 28/1932 UTC, followed by an M9.8 flare (R2/Moderate) at 28/1950 UTC; the largest event observed during the period. The asymmetric halo CME associated with the M9.8 flare, visible in LASCO/C2 coronagraph imagery at 28/2012 UTC, arrived at Earth on 01 Dec. Solar activity reached moderate levels on 01 Dec with M1 flares observed at 01/0439 UTC and 01/2120 UTC from Regions 3502 (N14, L=343, class/area=Cao/80 on 27 Nov) and 3500, respectively. Solar activity was at low levels with C-class flare activity observed over 27, 29-30 Nov, and 02-03 Dec.
Solar activity was low on 27 Nov, however, three distinct CMEs associated with four prominent eruptions were analyzed to have partial Earth-directed components. The first 27 Nov CME, visible in LASCO/C2 imagery at 27/0624 UTC off the SSW, was associated with a filament eruption near S26W27 at 27/0531 UTC (in SUVI 304 imagery). The second CME, visible in C2 imagery at 27/2000 off the SE, was associated with a C3.8 flare at 27/1837 UTC from an unnumbered area of flux near N20E15. The third CME, visible in C2 imagery at 27/2336 off the NW, was believed to be associated with a C5.5 flare at 27/2340 UTC from Region 3503 (N15, L=284, class/area=Hrx/10 on 27 Nov) and a filament eruption that occurred at around the same time just northward of 3503.
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 period.
Geomagnetic field activity was quiet under background solar wind conditions on 27 Nov through late 30 Nov. The solar wind environment became weakly enhanced at around 30/2330 UTC due to the arrival of CME(s) from 27 Nov. Active conditions were observed in the early hours of 01 Dec following CME arrival. An additional, stronger, solar wind enhancement was observed at 01/0853 UTC due to the arrival of a CME from 28 Nov. Periods of G1-G3 (Minor-Strong) geomagnetic storming were observed following CME arrival on 01 Dec, and active and G1 levels were observed in the early hours of 02 Dec as CME influences waned. Quiet and unsettled levels were observed on 03 Dec.
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 2023 Dec 07 1110Z: Bz: -0.6 nT
Bx: 2.1 nT | By: 1.4 nT | Total: 2.6 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:
06 Dec 2023 10.7-cm Flux: 142 / Ap: 017
07 Dec 2023 10.7-cm Flux: 142 / Ap: 017
08 Dec 2023 10.7-cm Flux: 142 / Ap: 017
Forecast:
Solar Flares: M-class flares expected (probability >=50%) Geo-Disturbance: Quiet (A<20 and K<4) Solar Proton Event: Quiet
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
04 December - 30 December 2023
Solar activity is expected to be low with a chance for M-class flare activity (R1-R2/Minor-Moderate) throughout the outlook period.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels on 05-09 Dec. Normal to moderate levels of flux are expected throughout the remainder of the period.
Geomagnetic field activity is likely to reach G2 (Moderate) storm levels on 04 Dec, G1 (Minor) levels on 05 Dec, and active levels on 06 Dec, in response to negative polarity CH HSS influences. Active conditions are likely on 12 Dec due to positive polarity CH HSS influences. Periods of G1 storms are likely on 18-19 and 22 Dec, with active levels likely on 23 Dec, due to the influences of positive polarity CH HSSs. Quiet and quiet to unsettled levels are expected to persist throughout the remainder of the period.
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.