Detailed Information

Solar Activity

Solar activity was active for the last 24 hours.

There were 17 flares with 13 C-class flares and 4 M-class flares in the last 24 hours. The maximum flare class was M1.5 from NOAA 4246 peaked at 01:28 UT. There were 6 solar radioburst all of which are type-III occurred in the last 24 hours. There was 2 CME event in the last 24 hours. The east-directed CME has the highest median velocity of 868 km/s with an angular width of 8 degrees and the west-directed CME has the highest median velocity of 419 km/s with an angular width of 42 degrees. The latest SDO/HMI Intensitygram data shows 7 active regions (NOAA 4246, 4248, 4250, 4252, 4254, 4255, and 4256) and the latest BBSO H-Alpha data shows 3 H-Alpha plages (NOAA 4249, 4251, and 4253). Based on farside data shows 1 regions due to return 17 Oct to 19 Oct from the east limb of the Solar disk.

Based on today's condition, solar activity for :
October 17th, 2025 04:00 UT - October 18th, 2025 03:59 UT is predicted to be active.
October 18th, 2025 04:00 UT - October 19th, 2025 03:59 UT is predicted to be active.
October 19th, 2025 04:00 UT - October 20th, 2025 03:59 UT is predicted to be active.

Geomagnetic Activity

The geomagnetic activity was on quiet level for the last 24 hours.

The solar wind speed decrease from 590 km/s to 279 km/s, north-south component of interplanetary magnetic field stable around 0.3 nT. There was geoeffective coronal hole at eastern equator, while the others at south-east and north pole were not geoeffective. CME on 16 October 2025 10:36 UT was mainly errupted toward north-west with speed of 419 km/s and angular width of 42°. The CME was geoeffective and is likely to have impact until next 3 days.

Quiet level geomagnetic activity is expected for the next 24 hours.
Active level geomagnetic activity is expected for 18 October 2025 04UT - 19 October 2025 04UT
Minor storm level geomagnetic activity is expected for 19 October 2025 04UT - 20 October 2025 04UT

Ionospheric Activity

The ionospheric activity for the last 24 hours cannot be evaluated due to problems with the CADI station. The S4 index values (condition of ionospheric scintillation) was higher than 0.8 and the maximum TEC index value was at 84.78, both over Pontianak.

The ionosphere activity on October 17th, 2025, 04:00 UT - October 18th, 2025, 03:59 UT is predicted to be quiet.  
The ionosphere activity on October 18th, 2025, 04:00 UT - October 19th, 2025, 03:59 UT is predicted to be quiet.  
The ionosphere activity on October 19th, 2025, 04:00 UT - October 20th, 2025, 03:59 UT is predicted to be minor.

Navigation

The error of the single frequency GPS positioning for last 24 hours was in medium level, based on ionospheric scintilation and TEC variation.

Based on ionospheric scintilation and TEC variation, the probability of error positioning in October 17th, 2025, 04:00 UT - October 18th, 2025, 03:59 UT is predicted at a medium level.
Based on ionospheric scintilation and TEC variation, the probability of error positioning in October 18th, 2025, 04:00 UT - October 19th, 2025, 03:59 UT is predicted at a slight level.
Based on ionospheric scintilation and TEC variation, the probability of error positioning in October 19th, 2025, 04:00 UT - October 20th, 2025, 03:59 UT is predicted at a normal level.

HF Radio Communication

MUF depression was in quiet condition and Short Wave Fadeout (SWF) cannot be evaluated for the last 24 hours.

The MUF depression on October 17th, 2025, 04:00 UT - October 18th, 2025, 03:59 UT is predicted on quiet level, due to previous of geomagnetic activity.
The MUF depression on October 18th, 2025, 04:00 UT - October 19th, 2025, 03:59 UT is predicted on quiet level, due to previous of geomagnetic activity.
The MUF depression on October 19th, 2025, 04:00 UT - October 20th, 2025, 03:59 UT is predicted on minor level, due to previous of geomagnetic activity.

The SWF on October 17th, 2025, 04:00 UT - October 18th, 2025, 03:59 UT is predicted in minor level due to the prediction of solar flare.
The SWF on October 18th, 2025, 04:00 UT - October 19th, 2025, 03:59 UT is predicted in minor level due to the prediction of solar flare. 
The SWF on October 19th, 2025, 04:00 UT - October 20th, 2025, 03:59 UT is predicted in minor level due to the prediction of solar flare.

Satellites

The electron flux was on high level for the last 24 hours.

High level of electron flux is expected for the next 24 hours.
High level of electron flux is expected for 18 October 2025 04UT - 19 October 2025 04UT
Low level of electron flux is expected for 19 October 2025 04UT - 20 October 2025 04UT

The flux of high-energy protons was quiet for the last 24 hours.

Based on today's conditon, the flux of high energy proton for :
October 17th, 2025 04:00 UT - October 18th, 2025 03:59 UT is predicted to be quiet.
October 18th, 2025 04:00 UT - October 19th, 2025 03:59 UT is predicted to be quiet.
October 19th, 2025 04:00 UT - October 20th, 2025 03:59 UT is predicted to be quiet.