Viewing archive of Tuesday, 18 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 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 2018IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z
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 (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 reached a peak of 561 km/s at 17/2218Z. Total IMF reached 5
nT at 18/1112Z. The maximum southward component of Bz reached -4 nT at
18/0515Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 10052 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on days one, two, and three (19 Sep, 20 Sep, 21
Sep).
III. Event Probabilities 19 Sep to 21 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Sep 068 Predicted 19 Sep-21 Sep 068/068/068 90 Day Mean 18 Sep 070
V. Geomagnetic A Indices
Observed Afr/Ap 17 Sep 009/011 Estimated Afr/Ap 18 Sep 007/008 Predicted Afr/Ap 19 Sep-21 Sep 006/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 19 Sep to 21 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 01% | 01% | 01% |
| 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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