Viewing archive of Friday, 29 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 29 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 119 Issued at 2200Z on 29 Apr 2011IA. Analysis of Solar Active Regions and Activity from 28-2100Z to 29-2100Z Solar activity has been at low levels for the past 24
hours. Region 1203 (N18E64) produced the largest event of the
period, a C3 flare at 29/0026Z. Region 1200 (S17E05) regained spots
and has developed into a beta group.
IB. Solar Activity Forecast
Solar activity is expected to be at
low levels for the next two days (30 April - 01 May). Very low to
low levels are expected on day three (02 May) as Regions 1199
(N18W62) and 1195 (S15W65) rotate off the west limb.
IIA. Geophysical Activity Summary 28-2100Z to 29-2100Z
The geomagnetic field has been at predominantly quiet levels for the
past 24 hours. However, late in the summary period, unsettled
conditions were observed. Measurements by the ACE spacecraft showed
an increase in solar wind speed from around 350 - 450 km/s. The total
interplanetary magnetic field increased from 5 - 18 nT over the
period with the negative component peaking at -10 nT. These changes
in solar wind indicate the arrival of a coronal hole high-speed
stream (CH HSS).
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be unsettled to active with isolated periods at minor
storm levels for the next three days (30 April - 02 May) as a CH HSS
becomes geoeffective.
III. Event Probabilities 30 Apr to 02 May
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 29 Apr 110 Predicted 30 Apr-02 May 110/105/105 90 Day Mean 29 Apr 107
V. Geomagnetic A Indices
Observed Afr/Ap 28 Apr 001/003 Estimated Afr/Ap 29 Apr 007/008 Predicted Afr/Ap 30 Apr-02 May 010/010-012/012-010/010
VI. Geomagnetic Activity Probabilities 30 Apr to 02 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 40% | 35% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 40% | 45% | 40% |
| Minor storm | 10% | 15% | 15% |
| Major-severe storm | 01% | 05% | 05% |
All times in UTC
Latest news
Sunday, 7 December 2025
M8.1 solar flare with earth-directed CME
Monday, 1 December 2025
X1.9 solar flare, Coronal hole faces Earth
Friday, 14 November 2025
X4.0 solar flare
Latest forum messages
AR4299 M8.1 CME 2025/12/06 137AR4294 / 4296 / 4298 415Space Weather Memes 761AR 4299 121New paper on the Gannon Storm 10-11 May 2024 2
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 | 2025/12/08 | X1.1 |
| Last M-flare | 2025/12/08 | M1.1 |
| 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 | 162.7 +70.9 |
| Last 30 days | 108 +13.3 |