Viewing archive of Monday, 9 April 2001
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 2001 Apr 09 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 099 Issued at 2200Z on 09 Apr 2001IA. Analysis of Solar Active Regions and Activity from 08-2100Z to 09-2100Z Solar activity increased to high levels. Region 9415
(S22W07) produced an M7/2B flare at 09/1534 UTC associated with a
1600 SFU Tenflare, Type II and IV radio sweeps, and a full-halo CME.
Region 9415 remained a large, magnetically complex group with a
strong, persistent magnetic delta configuration within the large
leader spot. The remaining regions were simply-structured and showed
no significant changes. New Region 9425 (S25W26) was numbered.
IB. Solar Activity Forecast
Solar activity is expected to be at
moderate to high levels. Region 9415 could produce another major
flare during the period.
IIA. Geophysical Activity Summary 08-2100Z to 09-2100Z
Geomagnetic field activity ranged from quiet to minor storm levels as
CME effects gradually subsided. The greater than 10 MeV proton flux
began to rise after today's major flare and was gradually increasing
as the period ended. A greater than 100 MeV proton flux enhancement
also followed the flare, but did not reach event levels.
IIB. Geophysical Activity Forecast
Geomagnetic field activity is
expected to decrease to quiet to unsettled levels on 10 April. The
CME associated with today's flare is expected to reach Earth during
the early hours of 11 April. Active to major storm levels will be
possible during 11 - 12 April as the CME passes Earth. The greater
than 10 MeV proton flux may increase to event levels early on 10
April.
III. Event Probabilities 10 Apr to 12 Apr
| Class M | 80% | 80% | 80% |
| Class X | 25% | 25% | 25% |
| Proton | 70% | 25% | 25% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 09 Apr 165 Predicted 10 Apr-12 Apr 165/160/160 90 Day Mean 09 Apr 167
V. Geomagnetic A Indices
Observed Afr/Ap 08 Apr 033/041 Estimated Afr/Ap 09 Apr 018/025 Predicted Afr/Ap 10 Apr-12 Apr 012/015-030/035-025/025
VI. Geomagnetic Activity Probabilities 10 Apr to 12 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 30% | 40% |
| Minor storm | 10% | 30% | 20% |
| Major-severe storm | 05% | 25% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 20% | 40% |
| Minor storm | 15% | 35% | 15% |
| Major-severe storm | 05% | 20% | 10% |
All times in UTC
Latest news
Tuesday, 15 April 2025
CME arrival, G3 storm watch
Friday, 28 March 2025
X1.1 solar flare
Monday, 24 March 2025
Coronal hole faces Earth
Latest forum messages
AR4073 1AR 4065 13Ask your obscure/"stupid" space weather questions. 376AR4064 29Filaments and prominences 106
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 | 2025/04/22 | M1.3 |
| Last geomagnetic storm | 2025/04/21 | Kp5+ (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| March 2025 | 134.2 -20.4 |
| April 2025 | 122.8 -11.4 |
| Last 30 days | 117.7 -15.6 |