Viewing archive of Saturday, 31 October 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 Oct 31 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 304 Issued at 2200Z on 31 Oct 2015IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M1 event observed at
31/1752Z from Region 2443 (N07E43). There are currently 4 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be moderate
with a slight chance for an X-class flare on days one, two, and three
(01 Nov, 02 Nov, 03 Nov).
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
404 km/s at 31/0905Z. Total IMF reached 9 nT at 30/2116Z. The maximum
southward component of Bz reached -5 nT at 31/2048Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (01 Nov), unsettled to
severe storm levels on day two (02 Nov) and active to major storm levels
on day three (03 Nov).
III. Event Probabilities 01 Nov to 03 Nov
| Class M | 55% | 55% | 55% |
| Class X | 15% | 15% | 15% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 31 Oct 119 Predicted 01 Nov-03 Nov 120/120/120 90 Day Mean 31 Oct 104
V. Geomagnetic A Indices
Observed Afr/Ap 30 Oct 006/006 Estimated Afr/Ap 31 Oct 005/005 Predicted Afr/Ap 01 Nov-03 Nov 008/008-036/065-033/050
VI. Geomagnetic Activity Probabilities 01 Nov to 03 Nov
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 20% | 25% |
| Minor storm | 05% | 35% | 40% |
| Major-severe storm | 01% | 40% | 30% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 01% | 05% |
| Minor storm | 30% | 10% | 10% |
| Major-severe storm | 20% | 90% | 85% |
All times in UTC
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