BKG

Space Weather

Situation Report, April 07, 2026

Overall Situation
3 /5
Strong
ⓘ Explanation of the WESIS Space Weather Scales at the end of the document
Classifications
Geomagnetic Disturbance start: April 03, 15:00 UTC
duration: 3.0 hours
G3
Strong
Disturbance Storm start: April 03, 20:00 UTC
duration: 8.0 hours
D2
Moderate
Solar Radio Flux start: March 30, 02:54 UTC
duration: 48 minutes
F2
Moderate
Electron Flux start: April 06, 07:25 UTC
duration: 15 minutes
E2
Moderate
X-Ray Flux start: April 04, 01:15 UTC
duration: 5 minutes
R2
Moderate
Warnings

Energy Supply

Space Operations

Communication

Navigation

Planetary K-index
Each vertical line represents the Kp index for the corresponding 3-hour interval. The x-axis represents time in the format Day.Month HH:MM UTC. The y-axis shows the index value. Warning thresholds from the NOAA Space Weather Prediction Center (SWPC) are plotted as needed.
Operational Comments
April 07, 2026: From the early morning of April 2 through the evening hours of April 3, there were significant geomagnetic disturbances, reaching a KP index of 7- (6.67) on April 3 between 3:00 p.m. and 6:00pm. The trigger was a combination of a coronal mass ejection (associated with a X1.4 flare in Beta-Gamma Region 4405) and the increased speed and density of the solar wind, caused by current equatorial coronal holes, which prolonged the disruptive effects on the Earth’s magnetic field until April 5.

Examples of Effects

  • Energy supply: Corrective actions may be necessary when controlling high-voltage grids; certain protection systems may trigger false alarms.
  • Space operations: Electrostatic charging of satellite surfaces is possible; low satellite orbits are affected by increased air drag; corrective measures for satellite orientation are necessary. Slightly increased likelihood of deep-dielectric charging.
  • Communication: Occasional problems with LF and HF radio communication may occur. Occasional HF radio blackouts on the sunlit side of the Earth.
  • Navigation systems: Satellite navigation systems may occasionally be affected. In rare cases, false echoes may occur in radar systems used for airspace surveillance. Low-frequency navigation signals in maritime and aviation use disrupted up to 15 minutes.
WESIS Space Weather Scales

The warning scale is based on the scale used by the National Oceanic and Atmospheric Administration (NOAA, USA) and comprises five levels, ranging from 1 (mild) to 5 (extreme). Statistically, extreme events occur one to four times per solar cycle. A cycle lasts 11 to 13 years.

D | Disturbance Storm Time (Dst) Index

The Dst Index is a primary gauge for geomagnetic storm severity, derived from a worldwide network of near-equatorial magnetometer stations. It calculates the globally averaged disturbance in the horizontal (H) component of Earth's magnetic field. As solar storms inject energetic ions into the magnetospheric ring current, they create a magnetic field that directly opposes Earth’s field, pushing Dst values deeply negative.

D1 < -50 nT
D2 < -75 nT
D3 < -100 nT
D4 < -200 nT
D5 < -400 nT
E | Electron Flux

The NOAA SWPC tracks the outer radiation belt using geostationary GOES satellites to issue Electron Flux Alerts. Warnings are activated when the >=2 MeV electron flux exceeds 1,000 pfu for three consecutive 5-minute intervals. This indicator warns operators of deep-dielectric charging, where accumulated internal electrical charges in spacecraft components can cause sudden arcing, leading to phantom commands or permanent satellite damage.

E1 1.000 electrons/ second
E2 10.000 e/s
E3 100.000 e/s
E4 1.000.000 e/s
E5 10.000.000 e/s
F | Solar Radio Flux

A parameter to which we actively contribute using the Solar Flux Telescope (CLT). Similar to the case of X-rays (see R-scale), the amounts of energy emitted during solar flares are reflected in the measurements of solar energy flux as so-called radio bursts. If the measurements increase abruptly, they are converted to the warning scale according to the following scheme: Increase in solar flux greater than:

F1 500 sfu
F2 1.000 sfu
F3 10.000 sfu
F4 20.000 sfu
F5 40.000 sfu
G | Geomagnetic Storms

The NOAA SWPC uses the G-Scale to categorize the severity of Geomagnetic Storms caused by solar wind variations. The scale directly maps to the planetary Kp-index, ranging from G1 (Kp = 5) up to G5 (Kp = 9). It serves as a vital operational warning system for power grid operators regarding transformer damage, pipeline engineers tracking corrosive currents, and satellite flight dynamics teams monitoring increased atmospheric drag and surface charging.

G1 Kp5
G2 Kp6
G3 Kp7
G4 Kp8
G5 Kp9
I | Electron Content

Total Electron Content (TEC) is the integrated electron density along a signal path through Earth's ionosphere, measured in TEC Units (TECU). Rapid increases in TEC, driven by solar EUV/X-ray flares and geomagnetic storms, directly modify the refractive index of the upper atmosphere. This causes signal phase delays and range errors for Global Navigation Satellite Systems (GNSS/GPS), high-frequency (HF) radio degradation, and satellite-to-ground communication disruptions, making it a critical metric for precision aviation and maritime navigation. We determine the total electron content using our own GNSS measurements.

I1 40 TECU
I2 50 TECU
I3 60 TECU
I4 70 TECU
I5 85 TECU
R | X-Ray Flux

The NOAA SWPC uses the R-Scale to categorize Radio Blackouts caused by sudden solar flare X-ray emissions. The primary metric is the peak X-ray flux measured in by GOES satellites, mapping directly to flare classes from R1 (M1 class) up to R5 (X20 class). It warns maritime, aviation, and military operators of sudden ionospheric absorptions that block HF radio communication and cause positioning errors in low-frequency navigation systems.

R1 0.00001 W/m² (M1 Flare)
R2 0.00005 W/m² (M5 Flare)
R3 0.0001 W/m² (X1 Flare)
R4 0.001 W/m² (X10 Flare)
R5 0.002 W/m² (X20 Flare)
S | Proton Flux

The NOAA Space Weather Prediction Center (SWPC) uses the S-Scale to categorize Solar Radiation Storms. The primary metric is the elevated proton flux (>=10 MeV), measured in Particle Flux Units (pfu) by GOES satellites. Stoms range from S1 (>=10 pfu) to S5 (>=100,000 pfu). It warns industries of polar HF radio communication failures, spacecraft orientation errors, and heightened radiation hazards.

S1 10 protons/second
S2 100 p/s
S3 1.000 p/s
S4 10.000 p/s
S5 100.000 p/s