Viewing archive of Sunday, 12 December 1999
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 1999 Dec 12 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 346 Issued at 2200Z on 12 DEC 1999IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z SOLAR ACTIVITY WAS LOW. ONLY ONE MINOR C-CLASS EVENT
WAS OBSERVED DURING THE PERIOD. MOST OF THE REGIONS ARE CURRENTLY
STABLE OR SHOWING SIGNS OF DECAY. NO NEW REGIONS WERE NUMBERED
TODAY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW.
IIA. Geophysical Activity Summary 11-2100Z to 12-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE. SOLAR WIND DATA INDICATED
A SIGNIFICANT INCREASE IN VELOCITY AND TEMPERATURE STARTING AROUND
12/1630Z. ACTIVE CONDITIONS WERE IMMEDIATELY OBSERVED AFTERWARDS.
THE GREATER THAN 2 MEV ELECTRONS AT GEOSYNCHRONOUS ORBIT WERE AT
HIGH LEVELS DURING THE PERIOD.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE PREDOMINANTELY QUIET TO ACTIVE ON THE FIRST DAY AS
THE CURRENT DISTURBANCE SUBSIDES. QUIET TO UNSETTLED CONDITIONS ARE
EXPECTED DURING THE REMAINDER OF THE PERIOD.
III. Event Probabilities 13 DEC to 15 DEC
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 12 DEC 159 Predicted 13 DEC-15 DEC 160/170/175 90 Day Mean 12 DEC 168
V. Geomagnetic A Indices
OBSERVED AFR/AP 11 DEC 006/007 ESTIMATED AFR/AP 12 DEC 012/010 PREDICTED AFR/AP 13 DEC-15 DEC 010/012-010/010-010/010
VI. Geomagnetic Activity Probabilities 13 DEC to 15 DEC
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 15% | 15% |
| Minor storm | 15% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 20% | 20% |
| Minor storm | 20% | 05% | 05% |
| Major-severe storm | 05% | 01% | 01% |
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