Viewing archive of Saturday, 16 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 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 197 Issued at 2200Z on 16 Jul 2011IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z
Solar activity has been at very low levels for the past
24 hours. Region 1254 (S22E36) produced the largest flare of the
period, a B6 event at 16/1705Z. The remaining regions on the visible
disk remained quiet and stable.
IB. Solar Activity Forecast
Solar activity is expected to be at
very low levels with a chance for C-class events for the next three
days (17-19 July).
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field has been at quiet levels for the past 24 hours.
Solar wind speed, as measured by the ACE spacecraft, has remained
nominal, around 380 km/s. 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 at predominantly quiet levels for day one (17 July).
An increase from quiet to quiet to unsettled levels is expected on
days two and three (18-19 July) as a recurrent coronal hole
high-speed stream moves into a geoeffective position.
III. Event Probabilities 17 Jul to 19 Jul
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Jul 094 Predicted 17 Jul-19 Jul 094/092/092 90 Day Mean 16 Jul 097
V. Geomagnetic A Indices
Observed Afr/Ap 15 Jul 005/006 Estimated Afr/Ap 16 Jul 003/005 Predicted Afr/Ap 17 Jul-19 Jul 005/005-008/008-010/010
VI. Geomagnetic Activity Probabilities 17 Jul to 19 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 10% | 15% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 20% |
| Minor storm | 01% | 01% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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