Viewing archive of Tuesday, 18 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 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 018 Issued at 2200Z on 18 Jan 2005IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity was moderate. Region 720 (N13W44)
continued to flare; however, the largest event in the past 24 hours
was an M4/2n at 18/1551 UTC. Although the region remains large and
magnetically complex, further sunspot restructuring and decay is
evident since yesterday. New Region 724 (S12W07) emerged on the
disk.
IB. Solar Activity Forecast
Solar activity is expected to be
moderate to high. Region 720, although diminishing in complexity,
still has sufficient potential for another major solar event.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field ranged from unsettled to severe storm levels.
The greater than 10 MeV proton event remains in progress with a
start time of 16/0210 UTC and a peak flux of 5040 pfu observed at
17/1750 UTC. The greater than 100 MeV proton event also remains in
progress with a start time of 17/1215 UTC and a 28 pfu peak flux
observed at 17/1700 UTC. GOES spacecraft electron sensors and ACE
SWEPAM instruments remain affected by the energetic proton event.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to remain at active to severe storm levels for the next 24
to 48 hours. The arrival of the CME associated with the X3 flare on
17 January has not yet been observed but is expected to contribute
to geomagnetic activity over the next 12 to 24 hours. The greater
than 100 MeV proton event is expected to end by early on 19 January,
barring a new major flare. The greater than 10 MeV proton event is
expected to remain in progress through late 19 to early 20 January.
III. Event Probabilities 19 Jan to 21 Jan
| Class M | 90% | 90% | 90% |
| Class X | 30% | 20% | 10% |
| Proton | 80% | 75% | 50% |
| PCAF | in progress | ||
IV. Penticton 10.7 cm Flux
Observed 18 Jan 124 Predicted 19 Jan-21 Jan 120/110/100 90 Day Mean 18 Jan 107
V. Geomagnetic A Indices
Observed Afr/Ap 17 Jan 027/063 Estimated Afr/Ap 18 Jan 040/080 Predicted Afr/Ap 19 Jan-21 Jan 030/075-020/030-015/020
VI. Geomagnetic Activity Probabilities 19 Jan to 21 Jan
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 25% | 25% |
| Minor storm | 60% | 50% | 20% |
| Major-severe storm | 10% | 05% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 25% | 50% |
| Minor storm | 70% | 60% | 30% |
| Major-severe storm | 20% | 15% | 05% |
All times in UTC
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