Viewing archive of Tuesday, 23 April 2013
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2013 Apr 23 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 113 Issued at 2200Z on 23 Apr 2013IA. Analysis of Solar Active Regions and Activity from 22-2100Z to 23-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
23/1414Z from Region 1726 (N13W49). There are currently 5 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares and a slight chance for an X-class flare on
days one, two, and three (24 Apr, 25 Apr, 26 Apr).
IIA. Geophysical Activity Summary 22-2100Z to 23-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 352 km/s at
23/1951Z. Total IMF reached 11 nT at 23/1521Z. The maximum southward
component of Bz reached -9 nT at 23/1900Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and three (24 Apr, 26 Apr)
and unsettled to minor storm levels on day two (25 Apr). Protons have a
slight chance of crossing threshold on days one, two, and three (24 Apr,
25 Apr, 26 Apr).
III. Event Probabilities 24 Apr to 26 Apr
| Class M | 40% | 40% | 40% |
| Class X | 15% | 15% | 15% |
| Proton | 15% | 15% | 15% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 23 Apr 118 Predicted 24 Apr-26 Apr 115/115/115 90 Day Mean 23 Apr 111
V. Geomagnetic A Indices
Observed Afr/Ap 22 Apr 005/004 Estimated Afr/Ap 23 Apr 007/007 Predicted Afr/Ap 24 Apr-26 Apr 011/008-016/012-011/018
VI. Geomagnetic Activity Probabilities 24 Apr to 26 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 15% |
| Minor storm | 05% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 25% | 25% | 25% |
| Major-severe storm | 25% | 35% | 25% |
All times in UTC
Latest news
Friday, 28 March 2025
X1.1 solar flare
Monday, 24 March 2025
Coronal hole faces Earth
Saturday, 22 March 2025
Strong G3 geomagnetic storm watch for 23 March
Latest forum messages
AR4046 126Incoming & Unnumbered Active Regions 1657Aurora photography hints for those of us with smartphones 48Large Coronal Hole 25 178LASCO Data Not Updating 5
More topicsSupport SpaceWeatherLive.com!
A lot of people come to SpaceWeatherLive to follow the Sun's activity or if there is aurora to be seen, but with more traffic comes higher server costs. Consider a donation if you enjoy SpaceWeatherLive so we can keep the website online!
Space weather facts
| Last X-flare | 2025/03/28 | X1.1 |
| Last M-flare | 2025/03/28 | M1.7 |
| Last geomagnetic storm | 2025/03/27 | Kp5 (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| February 2025 | 154.6 +17.6 |
| March 2025 | 128.3 -26.4 |
| Last 30 days | 128.3 -23.7 |