Viewing archive of Monday, 28 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 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 362 Issued at 2200Z on 28 Dec 2015IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was an M1 event observed at
28/1245Z from Region 2473 (S22W19). There are currently 2 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares and a slight chance for an X-class flare on
days one, two, and three (29 Dec, 30 Dec, 31 Dec).
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 548 km/s at
27/2300Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 1832 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (29 Dec), quiet to major
storm levels on day two (30 Dec) and unsettled to minor storm levels on
day three (31 Dec). Protons have a slight chance of crossing threshold
on days one, two, and three (29 Dec, 30 Dec, 31 Dec).
III. Event Probabilities 29 Dec to 31 Dec
| Class M | 50% | 50% | 50% |
| Class X | 10% | 10% | 10% |
| Proton | 10% | 10% | 10% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 28 Dec 112 Predicted 29 Dec-31 Dec 110/110/110 90 Day Mean 28 Dec 109
V. Geomagnetic A Indices
Observed Afr/Ap 27 Dec 007/006 Estimated Afr/Ap 28 Dec 007/007 Predicted Afr/Ap 29 Dec-31 Dec 008/010-021/032-015/026
VI. Geomagnetic Activity Probabilities 29 Dec to 31 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 40% | 40% |
| Minor storm | 05% | 25% | 20% |
| Major-severe storm | 01% | 05% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 25% | 25% | 25% |
| Major-severe storm | 25% | 60% | 60% |
All times in UTC
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