Viewing archive of Sunday, 17 April 2011
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 2011 Apr 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 107 Issued at 2200Z on 17 Apr 2011IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity remained at low levels. Region 1185
(N14, L=032) produced four C-class flares as it rotated off of the
solar limb. Region 1193 (N16E19) continues to increase in areal
coverage and maintains its beta-gamma magnetic configuration. Region
1190 (N14W53) showed decreases in both spot number and areal
coverage, however, it retains its beta-gamma magnetic configuration.
IB. Solar Activity Forecast
Solar activity is expected to be at
low levels, with C-class flares expected for the next three days
(18-20). There remains a chance for M-class flares during the
period.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was at quiet levels.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at predominantly quiet levels on days one and two
(18-19 April). Activity is expected to increase to quiet to
unsettled levels on day three (20 April), with a chance for active
levels as well as a slight chance for minor storm levels at high
latitudes. The increase in activity is due to a coronal hole
high-speed stream.
III. Event Probabilities 18 Apr to 20 Apr
| Class M | 40% | 40% | 40% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 17 Apr 114 Predicted 18 Apr-20 Apr 115/112/110 90 Day Mean 17 Apr 103
V. Geomagnetic A Indices
Observed Afr/Ap 16 Apr 002/004 Estimated Afr/Ap 17 Apr 003/005 Predicted Afr/Ap 18 Apr-20 Apr 005/005-005/005-010/010
VI. Geomagnetic Activity Probabilities 18 Apr to 20 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 35% |
| Minor storm | 01% | 01% | 10% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 40% |
| Minor storm | 01% | 01% | 15% |
| Major-severe storm | 01% | 01% | 05% |
Latest news
Monday, 22 April 2024
Lot's of sunspots! Big chance for major flare activity?
Saturday, 23 March 2024
X1.1 solar flare with earth-directed CME
Wednesday, 20 March 2024
Sunspot region 3615, G1 watch
Latest forum messages
Changelog/Featurelog 154What are these long and thin eruptions? 9Unspecified geomagnetic activity 947IMF - BT strength 8AR3654 1
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 | 2024/03/28 | X1.1 |
| Last M-flare | 2024/04/25 | M1.3 |
| Last geomagnetic storm | 2024/04/26 | Kp5+ (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| March 2024 | 104.9 -19.8 |
| Last 30 days | 136.8 +28.6 |