Viewing archive of Sunday, 21 June 2015
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 2015 Jun 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 172 Issued at 2200Z on 21 Jun 2015IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M3 event observed at
21/0944Z from Region 2367 (S18W64). There are currently 2 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be moderate
with a slight chance for an X-class flare on days one, two, and three
(22 Jun, 23 Jun, 24 Jun).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
370 km/s at 21/2055Z. Total IMF reached 11 nT at 21/1853Z. The maximum
southward component of Bz reached -6 nT at 21/1912Z. Protons greater
than 10 MeV at geosynchronous orbit reached a peak level of 14 pfu at
21/2055Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 1877 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to severe storm levels on day one (22 Jun), unsettled
to major storm levels on day two (23 Jun) and quiet to active levels on
day three (24 Jun). Protons are expected to cross threshold on day one
(22 Jun), are expected to cross threshold on day two (23 Jun) and are
likely to cross threshold on day three (24 Jun).
III. Event Probabilities 22 Jun to 24 Jun
| Class M | 75% | 75% | 75% |
| Class X | 20% | 20% | 20% |
| Proton | 99% | 90% | 70% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 21 Jun 136 Predicted 22 Jun-24 Jun 135/130/125 90 Day Mean 21 Jun 127
V. Geomagnetic A Indices
Observed Afr/Ap 20 Jun 002/003 Estimated Afr/Ap 21 Jun 007/008 Predicted Afr/Ap 22 Jun-24 Jun 032/060-026/042-011/015
VI. Geomagnetic Activity Probabilities 22 Jun to 24 Jun
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 30% | 25% |
| Minor storm | 35% | 40% | 05% |
| Major-severe storm | 50% | 25% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 01% | 05% | 15% |
| Minor storm | 10% | 15% | 30% |
| Major-severe storm | 90% | 85% | 30% |
All times in UTC
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