Viewing archive of Thursday, 21 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 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 202 Issued at 2200Z on 21 Jul 2011IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity was very low. Regions 1254 (S24W28) and
1259 (N25E32) remained present on the disk but were quiet and
stable.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low for the next 3 days (22-24 July).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was mostly unsettled for the majority of the
period, before decreasing to quiet conditions as Bz turned primarily north. 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 unsettled to active for days 1-2 (22-23 July), then
decreasing to mostly quiet on day 3 (24 July) as coronal hole
effects wane.
III. Event Probabilities 22 Jul to 24 Jul
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Jul 096 Predicted 22 Jul-24 Jul 096/095/095 90 Day Mean 21 Jul 096
V. Geomagnetic A Indices
Observed Afr/Ap 20 Jul 012/019 Estimated Afr/Ap 21 Jul 010/012 Predicted Afr/Ap 22 Jul-24 Jul 010/010-008/008-005/005
VI. Geomagnetic Activity Probabilities 22 Jul to 24 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 30% | 20% |
| Minor storm | 30% | 10% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 50% | 40% | 20% |
| Minor storm | 40% | 30% | 20% |
| Major-severe storm | 10% | 05% | 01% |
All times in UTC
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