Viewing archive of Saturday, 28 July 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 Jul 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 209 Issued at 2200Z on 28 Jul 2018IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z 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 (29 Jul, 30 Jul, 31 Jul).
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 443 km/s at 28/0035Z. Total IMF reached 5 nT at
27/2251Z. The maximum southward component of Bz reached -4 nT at
28/0120Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 3743 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on days one, two, and three (29 Jul, 30 Jul, 31
Jul).
III. Event Probabilities 29 Jul to 31 Jul
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 28 Jul 068 Predicted 29 Jul-31 Jul 068/070/070 90 Day Mean 28 Jul 071
V. Geomagnetic A Indices
Observed Afr/Ap 27 Jul 004/003 Estimated Afr/Ap 28 Jul 006/006 Predicted Afr/Ap 29 Jul-31 Jul 006/005-005/005-006/005
VI. Geomagnetic Activity Probabilities 29 Jul to 31 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 20% | 20% |
| Major-severe storm | 20% | 20% | 20% |
All times in UTC
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