Viewing archive of Tuesday, 17 April 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 Apr 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 107 Issued at 2200Z on 17 Apr 2018IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z
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 (18 Apr, 19 Apr, 20 Apr).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 487 km/s at 17/0757Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 4585 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (18 Apr, 20
Apr) and quiet to active levels on day two (19 Apr).
III. Event Probabilities 18 Apr to 20 Apr
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 17 Apr 069 Predicted 18 Apr-20 Apr 070/070/070 90 Day Mean 17 Apr 070
V. Geomagnetic A Indices
Observed Afr/Ap 16 Apr 003/002 Estimated Afr/Ap 17 Apr 004/005 Predicted Afr/Ap 18 Apr-20 Apr 007/008-008/012-007/010
VI. Geomagnetic Activity Probabilities 18 Apr to 20 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 35% | 30% |
| Minor storm | 01% | 20% | 10% |
| Major-severe storm | 01% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 15% |
| Minor storm | 20% | 30% | 30% |
| Major-severe storm | 10% | 45% | 35% |
All times in UTC
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