Viewing archive of Sunday, 16 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 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 259 Issued at 2200Z on 16 Sep 2018IA. 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. 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 (17 Sep, 18 Sep, 19 Sep).
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
reached a peak of 473 km/s at 16/0222Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 31051 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (17 Sep), quiet to unsettled
levels on day two (18 Sep) and quiet levels on day three (19 Sep).
III. Event Probabilities 17 Sep to 19 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Sep 069 Predicted 17 Sep-19 Sep 069/069/068 90 Day Mean 16 Sep 070
V. Geomagnetic A Indices
Observed Afr/Ap 15 Sep 007/005 Estimated Afr/Ap 16 Sep 009/010 Predicted Afr/Ap 17 Sep-19 Sep 014/016-007/008-006/005
VI. Geomagnetic Activity Probabilities 17 Sep to 19 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 20% | 15% |
| Minor storm | 10% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 25% | 30% | 20% |
| Major-severe storm | 40% | 30% | 20% |
All times in UTC
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