Viewing archive of Saturday, 15 September 2018
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 2018 Sep 15 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 258 Issued at 2200Z on 15 Sep 2018IA. Analysis of Solar Active Regions and Activity from 14-2100Z to 15-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 0 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
on days one, two, and three (16 Sep, 17 Sep, 18 Sep).
IIA. Geophysical Activity Summary 14-2100Z to 15-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 659 km/s at 14/2213Z. Total IMF reached 5
nT at 14/2205Z. The maximum southward component of Bz reached -2 nT at
15/1516Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 39830 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and two (16 Sep, 17 Sep) and
quiet to unsettled levels on day three (18 Sep).
III. Event Probabilities 16 Sep to 18 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 15 Sep 069 Predicted 16 Sep-18 Sep 069/069/069 90 Day Mean 15 Sep 070
V. Geomagnetic A Indices
Observed Afr/Ap 14 Sep 011/016 Estimated Afr/Ap 15 Sep 009/010 Predicted Afr/Ap 16 Sep-18 Sep 013/016-012/012-007/008
VI. Geomagnetic Activity Probabilities 16 Sep to 18 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 20% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 25% | 30% |
| Major-severe storm | 40% | 40% | 30% |
All times in UTC
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