Viewing archive of Thursday, 15 September 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 Sep 15 2204 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 258 Issued at 2200Z on 15 Sep 2005IA. Analysis of Solar Active Regions and Activity from 14-2100Z to 15-2100Z Solar activity was high. Region 808 (S11W22) produced
an X1.1/2n flare at 15/0838 UTC with an associated 450 sfu Tenflare.
This region was also responsible for several C and low M-class
flares throughout the period. Region 808 has changed very little in
the last 24 hours and retains a beta-gamma-delta magnetic
configuration.
IB. Solar Activity Forecast
Solar activity is expected to continue
at moderate to high levels. Region 808 is expected to continue to
produce M-class activity and still has the potential to produce an
isolated X-flare.
IIA. Geophysical Activity Summary 14-2100Z to 15-2100Z
The geomagnetic field was at quiet to severe storm levels.
Geomagnetic storming occurred in response to the arrival of a CME
associated with the double peak X-flare on 13 September. A 29 nT
sudden impulse was observed in the Boulder magnetometer at 15/0907
UTC. Solar wind speed at ACE rose from approximately 600 km/s to
near 900 km/s. The most disturbed periods occurred between 12 and 18
UTC following periods of southward Bz to near -15 nT. The greater
than 10 MeV proton flux increased during the shock passage to 235
pfu before declining to around 13 pfu by the end of the period. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at unsettled to minor storm levels with the
possibility of isolated major storm periods. Conditions should
decrease to quiet to unsettled on 17 and 18 September.
III. Event Probabilities 16 Sep to 18 Sep
| Class M | 70% | 65% | 60% |
| Class X | 50% | 40% | 30% |
| Proton | 50% | 40% | 30% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 15 Sep 119 Predicted 16 Sep-18 Sep 115/110/110 90 Day Mean 15 Sep 092
V. Geomagnetic A Indices
Observed Afr/Ap 14 Sep 013/025 Estimated Afr/Ap 15 Sep 025/050 Predicted Afr/Ap 16 Sep-18 Sep 018/025-008/015-008/010
VI. Geomagnetic Activity Probabilities 16 Sep to 18 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 20% | 20% |
| Minor storm | 20% | 10% | 10% |
| Major-severe storm | 10% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 25% |
| Minor storm | 30% | 15% | 10% |
| Major-severe storm | 15% | 05% | 01% |
All times in UTC
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