Viewing archive of Monday, 21 September 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 Sep 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 264 Issued at 2200Z on 21 Sep 2015IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
21/0518Z from Region 2420 (N10E64). There are currently 4 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (22 Sep, 23 Sep,
24 Sep).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
660 km/s at 21/0649Z. Total IMF reached 8 nT at 21/0824Z. The maximum
southward component of Bz reached -6 nT at 20/2152Z. Protons greater
than 10 MeV at geosynchronous orbit reached a peak level of 2 pfu at
20/2105Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 374 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (22 Sep, 24
Sep) and quiet to active levels on day two (23 Sep). Protons greater
than 10 Mev have a slight chance of crossing threshold on day one (22
Sep).
III. Event Probabilities 22 Sep to 24 Sep
| Class M | 40% | 30% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 10% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Sep 103 Predicted 22 Sep-24 Sep 105/105/110 90 Day Mean 21 Sep 103
V. Geomagnetic A Indices
Observed Afr/Ap 20 Sep 032/035 Estimated Afr/Ap 21 Sep 012/013 Predicted Afr/Ap 22 Sep-24 Sep 007/010-012/012-007/008
VI. Geomagnetic Activity Probabilities 22 Sep to 24 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 10% |
| Minor storm | 05% | 10% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 20% |
| Minor storm | 30% | 25% | 25% |
| Major-severe storm | 30% | 35% | 20% |
All times in UTC
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