Viewing archive of Sunday, 20 December 2015
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 2015 Dec 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 354 Issued at 2200Z on 20 Dec 2015IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C4 event observed at
19/2228Z. There are currently 2 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be low with a
slight chance for an M-class flare on days one, two, and three (21 Dec,
22 Dec, 23 Dec).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic
field has been at active to major storm levels for the past 24 hours.
Solar wind speed, as measured by the ACE spacecraft, reached a peak
speed of 536 km/s at 19/2326Z. Total IMF reached 18 nT at 20/2054Z. The
maximum southward component of Bz reached -18 nT at 20/0412Z. Electrons
greater than 2 MeV at geosynchronous orbit reached a peak level of 167
pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to minor storm levels on day one (21 Dec), quiet to
unsettled levels on day two (22 Dec) and quiet levels on day three (23
Dec).
III. Event Probabilities 21 Dec to 23 Dec
| Class M | 15% | 15% | 15% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Dec 117 Predicted 21 Dec-23 Dec 120/125/125 90 Day Mean 20 Dec 109
V. Geomagnetic A Indices
Observed Afr/Ap 19 Dec 008/010 Estimated Afr/Ap 20 Dec 038/059 Predicted Afr/Ap 21 Dec-23 Dec 019/020-009/010-006/005
VI. Geomagnetic Activity Probabilities 21 Dec to 23 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 15% | 10% |
| Minor storm | 10% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 15% |
| Minor storm | 35% | 25% | 20% |
| Major-severe storm | 40% | 20% | 10% |
All times in UTC
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