Viewing archive of Friday, 21 January 2005
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 2005 Jan 21 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.comJoint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 021 Issued at 2200Z on 21 Jan 2005
IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity was moderate. There were two M-class
events during the past 24 hours: an M1 from Region 720 (N13W83) at
1016 UTC, and an M1 from Region 719 (S06W90) at 1355 UTC. Two new
regions emerged on the disk today: Region 725 (S04W36) and Region
726 (S02E27).
IB. Solar Activity Forecast
Solar activity is expected to be
moderate. In addition, there is a fair chance for a major flare
and/or proton producing event from Region 720 as it rotates off the
solar disk.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was initially at quiet to unsettled levels
until a sudden impulse occurred at 1711 UTC. The sudden impulse was
preceded by a strong shock at the ACE spacecraft: solar wind
velocity jumped from about 600 km/s to 900-1000 km/s. The sudden
impulse at Earth was followed by magnetopause crossings at
geosynchronous orbit and severe levels of geomagnetic activity. The
shock and subsequent disturbed solar wind were most likely a
response to a CME associated with yesterday's X7 event. The greater
than 100 MeV proton event that began at 20/0650 UTC continued to
decline during the past 24 hours and dropped below threshold at
21/1845 UTC. The greater than 10 MeV proton event that began 16/0210
continues in progress: flux levels continue to decline with current
levels at about 50 PFU.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at minor to major storm levels for the next 12-24
hours (22 January) as the current disturbance persists. Conditions
should subside to mostly active levels by day two (23 January).
Unsettled to active levels are expected to prevail on the third day
(24 January) due to effects from a favorably positioned coronal
hole.
III. Event Probabilities 22 Jan to 24 Jan
Class M | 90% | 80% | 70% |
Class X | 30% | 20% | 10% |
Proton | 95% | 50% | 20% |
PCAF | in progress
|
IV. Penticton 10.7 cm Flux
Observed 21 Jan 114
Predicted 22 Jan-24 Jan 105/095/090
90 Day Mean 21 Jan 108
V. Geomagnetic A Indices
Observed Afr/Ap 20 Jan 010/012
Estimated Afr/Ap 21 Jan 045/070
Predicted Afr/Ap 22 Jan-24 Jan 030/060-020/025-015/015
VI. Geomagnetic Activity Probabilities 22 Jan to 24 Jan
A. Middle Latitudes |
Active | 30% | 45% | 40% |
Minor storm | 35% | 25% | 20% |
Major-severe storm | 30% | 05% | 05% |
B. High Latitudes |
Active | 15% | 25% | 35% |
Minor storm | 25% | 30% | 30% |
Major-severe storm | 55% | 25% | 05% |
All times in UTC
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