Viewing archive of Saturday, 23 July 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 Jul 23 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 204 Issued at 2200Z on 23 Jul 2011IA. Analysis of Solar Active Regions and Activity from 22-2100Z to 23-2100Z Solar activity was very low. Region 1254 (S26W54) and
Region 1259 (N23E02) are classified as Cao type spot groups. Both
regions remained quiet and stable. Multiple B class x-ray events
were observed, the largest a B5 at 23/1449 Z. The origin of the
activity is just beyond the east limb and is likely returning Region
1246 (L=329).
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low for the next three days (24-26 July).
IIA. Geophysical Activity Summary 22-2100Z to 23-2100Z
The geomagnetic field has been quiet to unsettled during the past 24
hours. Solar wind data observed at the ACE spacecraft indicated a
decrease in velocity from 600 km/s to about 500 km/s during the
period. The greater than 2 MeV electron flux at geosynchronous orbit
reached high levels during the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled with a slight chance of isolated
active periods for the next three days (24-26 July). The activity is
forecast due to the expected arrival of another coronal hole high
speed stream.
III. Event Probabilities 24 Jul to 26 Jul
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 23 Jul 088 Predicted 24 Jul-26 Jul 088/088/086 90 Day Mean 23 Jul 096
V. Geomagnetic A Indices
Observed Afr/Ap 22 Jul 010/010 Estimated Afr/Ap 23 Jul 008/008 Predicted Afr/Ap 24 Jul-26 Jul 006/006-005/005-009/009
VI. Geomagnetic Activity Probabilities 24 Jul to 26 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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