Viewing archive of Friday, 31 December 2004
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 2004 Dec 31 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.comJoint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 366 Issued at 2200Z on 31 Dec 2004
IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z
Solar activity was at moderate levels today. Region
715 (N04E34) produced an M4/2n event that occurred at 30/2218Z along
with an associated Tenflare (230 sfu), a Type IV spectral radio
sweep, and a Type II spectral radio sweep with an estimated shock
velocity of 1378 km/s. A related CME was observed on LASCO imagery
which appears to have a slight Earth directed component. A more
recent M1 x-ray flare occurred at 31/1445Z from this region, and due
to insufficient data, it is uncertain whether this flare produced a
CME. White light analysis has shown a decay in sunspot area over
the period although a small delta magnetic structure can be seen in
the southern most cluster of the penumbral spots. The remainder of
the disk/limbs were quiescent today. A new region was numbered
today as Region 717 (N07W56).
IB. Solar Activity Forecast
Solar activity is expected to be at
low to moderate levels. Region 715 remains capable of producing
M-class flare activity.
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
The geomagnetic field was at quiet to unsettled levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled levels through day one (1 Jan)
of the period. A recurrent high speed coronal hole stream and the
CME's that occurred yesterday in response to the M2/Sf event and the
M4/2n event that occurred today should induce active to minor storm
conditions on days two and three (2-3 Jan).
III. Event Probabilities 01 Jan to 03 Jan
Class M | 60% | 50% | 50% |
Class X | 10% | 10% | 10% |
Proton | 05% | 05% | 05% |
PCAF | green
|
IV. Penticton 10.7 cm Flux
Observed 31 Dec 099
Predicted 01 Jan-03 Jan 100/100/095
90 Day Mean 31 Dec 105
V. Geomagnetic A Indices
Observed Afr/Ap 30 Dec 012/015
Estimated Afr/Ap 31 Dec 008/009
Predicted Afr/Ap 01 Jan-03 Jan 008/012-015/020-015/015
VI. Geomagnetic Activity Probabilities 01 Jan to 03 Jan
A. Middle Latitudes |
Active | 20% | 35% | 35% |
Minor storm | 01% | 15% | 15% |
Major-severe storm | 01% | 05% | 05% |
B. High Latitudes |
Active | 25% | 40% | 35% |
Minor storm | 05% | 20% | 15% |
Major-severe storm | 01% | 10% | 05% |
All times in UTC
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