Viewing archive of Sunday, 18 December 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 Dec 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 353 Issued at 2200Z on 18 Dec 2016IA. 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
with a slight chance for a C-class flare on days one, two, and three (19
Dec, 20 Dec, 21 Dec).
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 467 km/s at 18/0245Z. Total IMF reached 11
nT at 17/2308Z. The maximum southward component of Bz reached -9 nT at
17/2311Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 1565 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and two (19 Dec, 20 Dec) and
unsettled to minor storm levels on day three (21 Dec).
III. Event Probabilities 19 Dec to 21 Dec
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Dec 072 Predicted 19 Dec-21 Dec 073/073/073 90 Day Mean 18 Dec 082
V. Geomagnetic A Indices
Observed Afr/Ap 17 Dec 003/003 Estimated Afr/Ap 18 Dec 010/010 Predicted Afr/Ap 19 Dec-21 Dec 011/015-012/015-017/025
VI. Geomagnetic Activity Probabilities 19 Dec to 21 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 40% |
| Minor storm | 10% | 10% | 25% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 10% |
| Minor storm | 30% | 30% | 25% |
| Major-severe storm | 40% | 40% | 60% |
All times in UTC
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