Last Updated: 2026-08-02 22:00 UTC
🟥 D-Layer Absorption & Space Weather Monitor
Live DRAP/GOES-style view for “why did 40 m just go to the pub?” moments.
Tropo conditions: Enhanced tropo expected over southern UK and nearby coasts.
External tropo check:
F5LEN Europe Tropo Forecast
Mode guide:
Tropo mode definitions (TR / AP / ducting etc.)
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 1 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Aug 02-Aug 04 2026 is 5.67 (NOAA Scale
G2).
NOAA Kp index breakdown Aug 02-Aug 04 2026
Aug 02 Aug 03 Aug 04
00-03UT 1.00 3.67 1.67
03-06UT 1.00 4.33 1.67
06-09UT 1.00 3.00 1.33
09-12UT 1.00 4.00 1.33
12-15UT 4.33 3.00 1.33
15-18UT 5.67 (G2) 2.00 1.33
18-21UT 3.33 2.00 1.67
21-00UT 4.00 1.33 1.33
Rationale: G1-G2 (Minor-Moderate) geomagnetic storms are likely on 02
Aug due to the influence of a CME that left the Sun on 30 Jul.
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 Aug 02-Aug 04 2026
Aug 02 Aug 03 Aug 04
S1 or greater 5% 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 Aug 02-Aug 04 2026
Aug 02 Aug 03 Aug 04
R1-R2 25% 25% 25%
R3 or greater 5% 5% 5%
Rationale: There remains a chance for R1-R2 (Minor-Moderate) radio
blackouts over 02-04 Aug due to the flare potential of multiple active
regions on the visible disk.
Issued: 2026 Jul 27 0325 UTC
Highlights of Solar and Geomagnetic Activity 20 - 26 July 2026 Solar activity was at low to R1 (Minor) levels this period. A total of 54 C-class and 6 R1 (Minor) events were observed. The largest, and most complex spot group, was Region 4493 (N06, L=158, class/area Eki/440 on 23 Jul). This region produced a total of 42 C-class and 5 M-class events, the largest an M3.6 at 22/0635 UTC. A 200 sfu 10 cm Burst was associated with this event. Region 4494 (S04, L=088, class/area Dac/120 on 26 Jul) produced the other R1 (Minor) event, an M3.2 at 26/1528 UTC. Associated with this event was a Type II Sweep with an estimated shock velocity of 1,057 km/s. No other significant activity was observed. No proton events were observed at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels on 20 and 26 Jul with the high value of 1,300 pfu observed at 20/1645 UTC. Geomagnetic field activity was at quiet to G1 (Minor) levels. Quiet levels were observed on 20 Jul. Levels increased to unsettled to active on 21 Jul to early on 24 Jul, with isolated G1 (Minor) levels observed late on 23 Jul. This activity was due to effects from a negative polarity CH HSS. Quiet conditions were observed most of 24 Jul and 25-26 Jul.
Forecast of Solar and Geomagnetic Activity 27 July - 22 August 2026 Solar activity is expected to be at mostly low levels with a chance for moderate R1 (Minor) levels 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 27 Jul, 02-03 Aug, 06-09 Aug, 12-16 Aug, and 22 Aug. The remainder of the outlook period is expected to be at normal to moderate levels. Geomagnetic field activity is expected to be at unsettled to active levels on 27-28 Jul due to potential weak CME effects. Unsettled to active levels are expected on 29-31 Jul, 04-07 Aug, 11-12 Aug, and 17-20 Aug with isolated G1 (Minor) levels possible on 19 Aug. This level of activity is due to recurrent CH HSS effects. Mostly quiet levels are expected for the remainder of the outlook period.
| Date (UTC) | F10.7 | Ap | Largest Kp |
|---|---|---|---|
| 2026-07-27 | 150 | 18 | 4 |
| 2026-07-28 | 150 | 15 | 3 |
| 2026-07-29 | 145 | 8 | 3 |
| 2026-07-30 | 140 | 8 | 3 |
| 2026-07-31 | 135 | 8 | 3 |
| 2026-08-01 | 130 | 5 | 2 |
| 2026-08-02 | 125 | 5 | 2 |
| 2026-08-03 | 125 | 5 | 2 |
| 2026-08-04 | 125 | 12 | 4 |
| 2026-08-05 | 120 | 15 | 3 |
| 2026-08-06 | 125 | 10 | 3 |
| 2026-08-07 | 130 | 7 | 2 |
| 2026-08-08 | 130 | 5 | 2 |
| 2026-08-09 | 130 | 5 | 2 |
Modelled MUF estimates based on current solar indices and UTC hour.
| Path | Estimated MUF | Notes |
|---|---|---|
| Western Europe → East Coast NA | 25 MHz | 20 m stable; 15 m closes by dusk |
| Western Europe → South America | 27 MHz | 17/20 m steady south path |
| Western Europe → Oceania (Short) | 20 MHz | Best chance at greyline; 17 m possible |
| Western Europe → SE Asia | 23 MHz | 20 m stable route; 17 m variable |
| Western Europe → Trans-equatorial Africa | 26 MHz | 17/20 m workable into night |
Latest DRAP absorption map (courtesy of NOAA SWPC):
Dark red areas indicate significant D-layer absorption. Useful for spotting potential HF blackouts.
G7IZU HF MUF Plot (Latest):
G7IZU Sporadic-E Map (Latest):
Both images auto-refresh regularly and reflect near-real-time ionospheric and Es propagation.