Viewing archive of Saturday, 27 September 2025
Solar activity report
Report of Solar-Geophysical Activity 2025 Sep 27 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 270 Issued at 2200Z on 27 Sep 2025IA. Analysis of Solar Active Regions and Activity from 26-2100Z to 27-2100Z Solar activity has been at moderate levels for the past 24
hours. There are currently 9 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be moderate on
days one, two, and three (28 Sep, 29 Sep, 30 Sep).
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 434 km/s at 26/2115Z. Total IMF reached 10
nT at 27/2058Z. The maximum southward component of Bz reached -8 nT at
27/1857Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1723 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and two (28 Sep, 29 Sep) and
quiet to unsettled levels on day three (30 Sep).
III. Event Probabilities 28 Sep to 30 Sep
| Class M | 55% | 55% | 55% |
| Class X | 05% | 05% | 05% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 27 Sep 164 Predicted 28 Sep-30 Sep 165/160/160 90 Day Mean 27 Sep 149
V. Geomagnetic A Indices
Observed Afr/Ap 26 Sep 006/007 Estimated Afr/Ap 27 Sep 007/007 Predicted Afr/Ap 28 Sep-30 Sep 013/018-011/014-007/008
VI. Geomagnetic Activity Probabilities 28 Sep to 30 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 25% |
| Minor storm | 15% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 30% | 30% |
| Major-severe storm | 45% | 40% | 35% |
All times in UTC
Latest news
Monday, 19 January 2026
CME impact! S4 solar radiation storm
Sunday, 18 January 2026
X1.9 solar flare with earth-directed CME
Wednesday, 31 December 2025
Happy New Year! Celebrate with an M7.1 solar flare!
Latest forum messages
Incoming & Unnumbered Active Regions 113X1.9 CME 1231Space Weather Memes 775AR 4345 19AR 14342/14344 8
More topicsSupport SpaceWeatherLive.com!
A lot of people come to SpaceWeatherLive to follow the Solar activity or if there is a chance to see the aurora, but with more traffic comes higher costs to keep the servers online. If you like SpaceWeatherLive and want to support the project you can choose a subscription for an ad-free site or consider a donation. With your help we can keep SpaceWeatherLive online!
Space weather facts
| Last X-flare | 2026/01/18 | X1.9 |
| Last M-flare | 2026/01/21 | M1.1 |
| Last geomagnetic storm | 2026/01/20 | Kp8 (G4) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| December 2025 | 124 +32.2 |
| January 2026 | 107.3 -16.8 |
| Last 30 days | 111.9 +4 |