Viewing archive of Friday, 18 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 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 261 Issued at 2200Z on 18 Sep 2015IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C6 event observed at
17/2115Z from Region 2415 (S20W16). There are currently 3 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 (19 Sep, 20 Sep,
21 Sep).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
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
465 km/s at 18/1544Z. Total IMF reached 7 nT at 18/1209Z. The maximum
southward component of Bz reached -6 nT at 18/1149Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 3502 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (19 Sep), unsettled to minor
storm levels on day two (20 Sep) and active to minor storm levels on day
three (21 Sep).
III. Event Probabilities 19 Sep to 21 Sep
| Class M | 25% | 25% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Sep 103 Predicted 19 Sep-21 Sep 105/110/110 90 Day Mean 18 Sep 104
V. Geomagnetic A Indices
Observed Afr/Ap 17 Sep 012/011 Estimated Afr/Ap 18 Sep 010/011 Predicted Afr/Ap 19 Sep-21 Sep 014/016-018/025-021/030
VI. Geomagnetic Activity Probabilities 19 Sep to 21 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 40% | 40% |
| Minor storm | 10% | 20% | 20% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 30% | 30% | 30% |
| Major-severe storm | 35% | 50% | 50% |
All times in UTC
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