Viewing archive of Wednesday, 21 April 2004
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 2004 Apr 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 112 Issued at 2200Z on 21 Apr 2004IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity has been low. Region 596 (S07E19)
produced the only C-class events in the past 24 hours. The daily
consensus for this region has it as a magnetic beta-gamma
configuration, however, earlier in the period a small delta
configuration developed. A new region was numbered today as Region
598 (S05W30).
IB. Solar Activity Forecast
Solar activity is expected to be low.
Region 596 is expected to continue producing C-class flares with a
chance for an isolated M-class event.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field has been at quiet to unsettled levels.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be predominately quiet to unsettled.
III. Event Probabilities 22 Apr to 24 Apr
| Class M | 25% | 25% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Apr 113 Predicted 22 Apr-24 Apr 115/120/120 90 Day Mean 21 Apr 107
V. Geomagnetic A Indices
Observed Afr/Ap 20 Apr 004/004 Estimated Afr/Ap 21 Apr 006/006 Predicted Afr/Ap 22 Apr-24 Apr 005/008-010/010-010/012
VI. Geomagnetic Activity Probabilities 22 Apr to 24 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 20% | 20% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 25% | 25% |
| Minor storm | 05% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
Whitehorse, YTAnchorage, AK, Fairbanks, AK, Juneau, AK, Utqiagvik, AK
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
Unspecified geomagnetic activity 2221Incoming & Unnumbered Active Regions 1660AR4048 114New satellites - Proba-3, PUNCH, SWFO-L1, GOES-U/19 36Filaments and prominences 750
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!
Latest alerts
10:00 UTC - Hemispheric Power Index
The OVATION model predicts the Hemispheric Power Index to reach 78GW at 10:32 UTC
04:15 UTC - Geomagnetic activity
Minor G1 geomagnetic storm (Kp5) Threshold Reached: 04:05 UTC
03:15 UTC - Geomagnetic activity
Moderate G2 geomagnetic storm (Kp6) Threshold Reached: 02:59 UTC
01:00 UTC - Geomagnetic activity
Minor G1 geomagnetic storm (Kp5) Threshold Reached: 00:51 UTC
Friday, 4 April 2025
23:30 UTC - Geomagnetic activity
Minor G1 geomagnetic storm (Kp5) Threshold Reached: 23:17 UTC
Space weather facts
| Last X-flare | 2025/03/28 | X1.1 |
| Last M-flare | 2025/04/01 | M2.5 |
| Last geomagnetic storm | 2025/04/04 | Kp5+ (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| March 2025 | 134.2 -20.4 |
| April 2025 | 148 +13.8 |
| Last 30 days | 130.9 -15.2 |