Viewing archive of Wednesday, 21 September 2016
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 2016 Sep 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 265 Issued at 2200Z on 21 Sep 2016IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
21/1151Z from Region 2595 (N08W90). There are currently 2 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (22 Sep,
23 Sep, 24 Sep).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 637 km/s at 21/0537Z. Total IMF reached 5
nT at 21/0155Z. The maximum southward component of Bz reached -4 nT at
20/2315Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 1366 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (22 Sep, 23 Sep)
and quiet levels on day three (24 Sep).
III. Event Probabilities 22 Sep to 24 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Sep 086 Predicted 22 Sep-24 Sep 085/085/085 90 Day Mean 21 Sep 086
V. Geomagnetic A Indices
Observed Afr/Ap 20 Sep 015/018 Estimated Afr/Ap 21 Sep 010/010 Predicted Afr/Ap 22 Sep-24 Sep 007/008-007/008-006/005
VI. Geomagnetic Activity Probabilities 22 Sep to 24 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 10% |
| Minor storm | 01% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 30% | 15% |
| Major-severe storm | 20% | 35% | 15% |
All times in UTC
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