Detailed Information

Solar Activity

Solar activity was eruptive for May 26th, 2025 04.00 UT - May 27th, 2026 03.59 UT.
Solar activity was eruptive for May 27th, 2026 04.00 UT - May 28th, 2026 03.59 UT.
Solar activity was eruptive for May 28th, 2026 04.00 UT - May 29th, 2026 03.59 UT.

A total of four flares were observed, all of which were C-class. Specifically, four C-class flares were detected, while no M-class or X-class flares were observed. The strongest event was a C3.2 flare originating from NOAA 14452, peaking at 15:16 UT. No solar radio bursts were reported. Meanwhile, two coronal mass ejections were observed. One CME was detected from the western limb with a speed of 196 kilometers per second and an angular width of 10 degrees. Another CME originated from the eastern limb with a speed of 511 kilometers per second and an angular width of 20 degrees.

On the visible disk, SDO HMI observations revealed eleven active NOAA 14443, NOAA 14444, NOAA 14445, NOAA 14446, NOAA 14447, NOAA 14448, NOAA 14449, NOAA 14452, NOAA 14453, NOAA 14454, and NOAA 14455. Additionally, one H-alpha plage, NOAA 14450, was identified by BBSO. Two active regions are projected to return from the farside between 29 May and 31 May. 

Based on predictions from the Random Forest model, solar activity for :
May 29th, 2026 04:00 UT - May 30th, 2026 03:59 UT is predicted to be active.
May 30th, 2026 04:00 UT - May 31st, 2026 03:59 UT is predicted to be eruptive.
May 31st, 2026 04:00 UT - June 1st, 2026 03:59 UT is predicted to be eruptive.
June 1st, 2026 04:00 UT - June 2nd, 2026 03:59 UT is predicted to be eruptive.

Geomagnetic Activity

The geomagnetic activity was at quiet level on 26 May 2026 04:00UT - 27 May 2026 03:59UT.
The geomagnetic activity was at quiet level on 27 May 2026 04:00UT - 28 May 2026 03:59UT.
The geomagnetic activity was at quiet level on 28 May 2026 04:00UT - 29 May 2026 03:59UT.

The solar wind speed fluctuate between 356 km/s and 437 km/s, north-south component of interplanetary magnetic field fluctuate between -6.6 nT and 6.5 nT. There were geoeffective coronal holes at north pole, western equator and central equator, while the others at north-east were not geoeffective. CME on 28 May 2026 09:00 UT was mainly errupted toward south-west with speed of 196 km/s and angular width of 10°. The CME was geoeffective and is likely to have not impact until next 4 days.

Quiet level geomagnetic activity is expected for 29 May 2026 04:00UT - 30 May 2026 03:59UT.
Quiet level geomagnetic activity is expected for 30 May 2026 04:00UT - 31 May 2026 03:59UT.
Quiet level geomagnetic activity is expected for 31 May 2026 04:00UT - 01 June 2026 03:59UT.
Quiet level geomagnetic activity is expected for 01 June 2026 04:00UT - 02 June 2026 03:59UT.

 

 

Ionospheric Activity

Ionosphere was quiet for May 26th, 2025 04.00 UT - May 27th, 2026 03.59 UT.
Ionosphere was quiet for May 27th, 2026 04.00 UT - May 28th, 2026 03.59 UT.
Ionosphere was disturbed in minor level for May 28th, 2026 04.00 UT - May 29th, 2026 03.59 UT.

There was 45 minutes depression of foF2 lower than 30% of its median value. There was 30 minutes increment of fmin more than 30% of its median values. The Spread-F was not detected for the last 24 hours. There was 19 hours and 30 minutes Sporadic-E occurred in the night and daytime with foEs value exceeded the foF2 for several times. The S4 index values (condition of ionospheric scintillation ) was less than 0.5 and the maximum TEC index value was at 78.68, both over Pontianak.

The ionosphere activity on May 29th, 2026, 04:00 UT - May 30th, 2026, 03:59 UT is predicted to be quiet.  
The ionosphere activity on May 30th, 2026, 04:00 UT - May 31st, 2026, 03:59 UT is predicted to be quiet.  
The ionosphere activity on May 31st, 2026, 04:00 UT - June 1st, 2026, 03:59 UT is predicted to be quiet.
The ionosphere activity on June 1st, 2026, 04:00 UT - May June, 2026, 03:59 UT is predicted to be quiet.

Navigation

The error of the single frequency GPS positioning for May 26th, 2025 04.00 UT - May 27th, 2026 03.59 UT was in normal level, based on ionospheric scintilation and TEC variation.
The error of the single frequency GPS positioning for May 27th, 2026 04.00 UT - May 28th, 2026 03.59 UT was in normal level, based on ionospheric scintilation and TEC variation.
The error of the single frequency GPS positioning for May 28th, 2026 04.00 UT - May 29th, 2026 03.59 UT was in normal level, based on ionospheric scintilation and TEC variation.

Based on ionospheric scintilation and TEC variation, the probability of error positioning in May 29th, 2026, 04:00 UT - May 30th, 2026, 03:59 UT is predicted at a normal level.
Based on ionospheric scintilation and TEC variation, the probability of error positioning in May 30th, 2026, 04:00 UT - May 31st, 2026, 03:59 UT is predicted at a normal level.
Based on ionospheric scintilation and TEC variation, the probability of error positioning in May 31st, 2026, 04:00 UT - June 1st, 2026, 03:59 UT is predicted at a normal level.
Based on ionospheric scintilation and TEC variation, the probability of error positioning in June 1st, 2026, 04:00 UT - June 2nd, 2026, 03:59 UT is predicted at a normal level.

HF Radio Communication

MUF depression was on quiet level and Short Wave Fadeout (SWF) was in moderate level for May 26th, 2025 04.00 UT - May 27th, 2026 03.59 UT.
MUF depression was on quiet level and Short Wave Fadeout (SWF) was on minor level for May 27th, 2026 04.00 UT - May 28th, 2026 03.59 UT.
MUF depression was on moderate level and Short Wave Fadeout (SWF) was on minor level for May 28th, 2026 04.00 UT - May 29th, 2026 03.59 UT.

The MUF depression on May 29th, 2026, 04:00 UT - May 30th, 2026, 03:59 UT is predicted on quiet level, due to previous of geomagnetic activity.
The MUF depression on May 30th, 2026, 04:00 UT - May 31st, 2026, 03:59 UT is predicted on quiet level, due to previous of geomagnetic activity.
The MUF depression on May 31st, 2026, 04:00 UT - June 1st, 2026, 03:59 UT is predicted on quiet level, due to previous of geomagnetic activity.
The MUF depression on June 1st, 2026, 04:00 UT - June 2nd, 2026, 03:59 UT is predicted on quiet level, due to previous of geomagnetic activity.

The SWF on May 29th, 2026, 04:00 UT - May 30th, 2026, 03:59 UT is predicted in minor level due to the prediction of solar flare.
The SWF on May 30th, 2026, 04:00 UT - May 31st, 2026, 03:59 UT is predicted in quiet level due to the prediction of solar flare. 
The SWF on May 31st, 2026, 04:00 UT - June 1st, 2026, 03:59 UT is predicted in quiet level due to the prediction of solar flare.
The SWF on June 1st, 2026, 04:00 UT - June 2nd, 2026, 03:59 UT is predicted in quiet level due to the prediction of solar flare.

Satellites

The electron flux was at low level on 26 May 2026 04:00UT - 27 May 2026 03:59UT.
The electron flux was at low level on 27 May 2026 04:00UT - 28 May 2026 03:59UT.
The electron flux was at low level on 28 May 2026 04:00UT - 29 May 2026 03:59UT.

Low level of electron flux is expected for 29 May 2026 04:00UT - 30 May 2026 03:59UT.
Low level of electron flux is expected for 30 May 2026 04:00UT - 31 May 2026 03:59UT.
Low level of electron flux is expected for 31 May 2026 04:00UT - 01 June 2026 03:59UT.
Low level of electron flux is expected for 01 June 2026 04:00UT - 02 June 2026 03:59UT.

The flux of high-energy protons was event in progress for May 26th, 2025 04.00 UT - May 27th, 2026 03.59 UT.
The flux of high-energy protons was quiet for May 27th, 2026 04.00 UT - May 28th, 2026 03.59 UT.
The flux of high-energy protons was quiet for May 28th, 2026 04.00 UT - May 29th, 2026 03.59 UT.

Based on the observed conditions from the preceding 24 hours, the flux of high energy proton for :
May 29th, 2026 04:00 UT - May 30th, 2026 03:59 UT is predicted to be quiet.
May 30th, 2026 04:00 UT - May 31st, 2026 03:59 UT is predicted to be quiet.
May 31st, 2026 04:00 UT - June 1st, 2026 03:59 UT is predicted to be quiet.
June 1st, 2026 04:00 UT - June 2nd, 2026 03:59 UT is predicted to be quiet.