These images are pulled directly from SWPC’s public image products and are useful for quick visual context.
Next 3 days (plain-English band outlook): - Storminess: Kp ≈ 6.7 (stormy). Higher Kp usually degrades polar HF and adds flutter. - Solar “baseline”: F10.7 ≈ 102.0 (low). Higher tends to help 15m/10m. - Dayside HF blackout risk (R1–R2): about 10% / 10% / 10% per day (if a flare hits, bands can drop suddenly on the sunlit side). HF: - 160m: mostly night-only for distance; daytime often poor due to absorption + noise. - 80m: best after local sunset through pre-dawn; daytime often limited by D-layer absorption. - 60m: good for regional/nighttime; usually more stable than 80m in noisier environments. - 40m: reliable day/night bridge band; expect best DX around grayline and at night. - 30m: often steady DX when 20m is crowded/unstable; less sensitive to MUF swings. - 20m: primary DX workhorse; if Kp is unsettled/stormy, avoid polar routes first. - 17m: similar to 20m but more “selective”; benefits from higher F10.7. - 15m: spotty; check midday/grayline. - 12m: often intermittent; worth checking midday. - 10m: often closed or short-skip; still check around local noon. VHF/UHF & satellites: - 6m: mostly line-of-sight unless there is Es/TEP; space weather matters less than seasonal Es. - 2m/70cm: normally line-of-sight; if Kp is high, aurora can enable unique paths but may distort signals. - Satellites: stormy days can increase fades/scintillation (especially on higher frequencies and some geometries).
:Product: 3-Day Forecast
:Issued: 2026 Mar 21 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 7 (NOAA Scale
G3).
The greatest expected 3 hr Kp for Mar 21-Mar 23 2026 is 6.67 (NOAA Scale
G3).
NOAA Kp index breakdown Mar 21-Mar 23 2026
Mar 21 Mar 22 Mar 23
00-03UT 6.67 (G3) 4.67 (G1) 3.33
03-06UT 6.33 (G2) 5.00 (G1) 4.33
06-09UT 5.67 (G2) 4.33 3.00
09-12UT 5.00 (G1) 4.00 3.00
12-15UT 3.33 2.67 2.00
15-18UT 4.00 3.33 2.00
18-21UT 4.67 (G1) 4.33 3.33
21-00UT 4.33 4.33 3.00
Rationale: G1-G3 (Minor-Strong) geomagnetic storm conditions are
expected on 21 Mar with G1 (Minor) conditions likely on 22 Mar due to
persistent CME effects followed by HSS activity.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Mar 21-Mar 23 2026
Mar 21 Mar 22 Mar 23
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for Mar 21-Mar 23 2026
Mar 21 Mar 22 Mar 23
R1-R2 10% 10% 10%
R3 or greater 1% 1% 1%
Rationale: No R1 (Minor) or greater radio blackouts are expected. No
significant active region flare activity is forecast.
Next 7–10 days (SWPC 27-day outlook, simplified): - Day-by-day (UTC): unavailable (SWPC 27-day outlook table not fetched; check Status page / cache warmer). - These are probabilistic outlooks. Confirm with a quick on-air scan (FT8/WSPR/beacons).
:Product: 27-day Space Weather Outlook Table 27DO.txt :Issued: 2026 Mar 16 0302 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # https://www.swpc.noaa.gov/content/subscription-services # # 27-day Space Weather Outlook Table # Issued 2026-03-16 # # UTC Radio Flux Planetary Largest # Date 10.7 cm A Index Kp Index 2026 Mar 16 108 15 4 2026 Mar 17 108 10 3 2026 Mar 18 105 8 3 2026 Mar 19 105 5 2 2026 Mar 20 105 10 3 2026 Mar 21 100 35 5 2026 Mar 22 102 25 5 2026 Mar 23 105 15 4 2026 Mar 24 110 15 4 2026 Mar 25 100 18 5 2026 Mar 26 110 10 3 2026 Mar 27 120 8 3 2026 Mar 28 125 5 2 2026 Mar 29 125 5 2 2026 Mar 30 125 15 4 2026 Mar 31 125 10 3 2026 Apr 01 130 5 2 2026 Apr 02 135 5 2 2026 Apr 03 140 18 5 2026 Apr 04 135 20 5 2026 Apr 05 135 8 3 2026 Apr 06 130 15 4 2026 Apr 07 135 8 3 2026 Apr 08 130 5 2 2026 Apr 09 125 25 5 2026 Apr 10 120 40 6 2026 Apr 11 115 20 5
:Product: Geophysical Alert Message wwv.txt :Issued: 2026 Mar 21 0605 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # # Geophysical Alert Message # Solar-terrestrial indices for 20 March follow. Solar flux 102 and estimated planetary A-index 34. The estimated planetary K-index at 0600 UTC on 21 March was 6.00. Space weather for the past 24 hours has been strong. Geomagnetic storms reaching the G3 level occurred. Space weather for the next 24 hours is predicted to be moderate. Geomagnetic storms reaching the G2 level are expected.
This is a lightweight, operator-focused heuristic based on Kp and F10.7. It is not a prediction—validate with on-air checks.
| Band group | Rating | Why |
|---|---|---|
| 10–12–15 m | poor | Low solar flux and/or elevated geomagnetic activity. |
| 17–20 m | good | Mid bands often remain workable unless storms are strong. |
| 30–40 m | good | Often workable; watch storm effects on longer/high-latitude paths. |
| 60–80 m | fair | Lower bands can work well at night; performance is noise/absorption-limited. |