Viewing archive of Thursday, 21 December 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 Dec 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 355 Issued at 2200Z on 21 Dec 2023IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M4 event observed at
21/0538Z from Region 3519 (S12W72). There are currently 8 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (22 Dec, 23 Dec,
24 Dec).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 440 km/s at 21/2136Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 1273 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on day one (22 Dec), quiet to active levels on day
two (23 Dec) and quiet to unsettled levels on day three (24 Dec).
III. Event Probabilities 22 Dec to 24 Dec
| Class M | 40% | 40% | 40% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Dec 194 Predicted 22 Dec-24 Dec 194/190/190 90 Day Mean 21 Dec 149
V. Geomagnetic A Indices
Observed Afr/Ap 20 Dec 007/009 Estimated Afr/Ap 21 Dec 004/005 Predicted Afr/Ap 22 Dec-24 Dec 005/005-010/012-008/008
VI. Geomagnetic Activity Probabilities 22 Dec to 24 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 25% | 10% |
| Minor storm | 01% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 15% | 20% | 20% |
| Major-severe storm | 10% | 25% | 20% |
All times in UTC
Latest news
Monday, 1 December 2025
X1.9 solar flare, Coronal hole faces Earth
Friday, 14 November 2025
X4.0 solar flare
Tuesday, 11 November 2025
X5.1 solar flare, G4 geomagnetic storm watch
Latest forum messages
AR4294 / 4296 / 4298 291Unspecified geomagnetic activity 39Space Weather Memes 760Current Farside Activity 233AR 4299 23
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 | 2025/12/01 | X1.9 |
| Last M-flare | 2025/12/04 | M6.0 |
| Last geomagnetic storm | 2025/12/04 | Kp5 (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| November 2025 | 91.8 -22.8 |
| December 2025 | 186 +94.2 |
| Last 30 days | 106.3 +12.6 |