Viewing archive of Monday, 18 October 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Oct 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 291 Issued at 2200Z on 18 Oct 2021IA. 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 1 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 Oct, 20 Oct, 21 Oct).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 385 km/s at 18/1507Z. Total IMF reached 12
nT at 18/0428Z. The maximum southward component of Bz reached -8 nT at
17/2117Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 432 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and three (19 Oct, 21 Oct)
and quiet levels on day two (20 Oct).
III. Event Probabilities 19 Oct to 21 Oct
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Oct 076 Predicted 19 Oct-21 Oct 076/076/076 90 Day Mean 18 Oct 083
V. Geomagnetic A Indices
Observed Afr/Ap 17 Oct 006/012 Estimated Afr/Ap 18 Oct 008/010 Predicted Afr/Ap 19 Oct-21 Oct 012/012-007/008-008/010
VI. Geomagnetic Activity Probabilities 19 Oct to 21 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 25% | 30% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 30% | 30% |
| Major-severe storm | 35% | 30% | 35% |
All times in UTC
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