Viewing archive of Saturday, 16 October 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 Oct 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 289 Issued at 2200Z on 16 OCT 1999IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z SOLAR ACTIVITY REMAINED AT LOW LEVELS. REGION 8731
(N12W03) SHOWED MINOR GROWTH INCLUDING THE RE-FORMATION OF A
MAGNETIC DELTA CONFIGURATION NEAR REGION CENTER. IT PRODUCED
ISOLATED C-CLASS SUBFLARES DURING THE PERIOD. REGION 8728 (N23W26)
ALSO PRODUCED ISOLATED C-CLASS SUBFLARES, BUT WAS STABLE IN TERMS OF
SIZE AND MAGNETIC STRUCTURE. THE REMAINING REGIONS WERE EITHER
STABLE OR DECLINING. NEW REGION 8735 (N18E40) WAS NUMBERED.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE AT
LOW TO MODERATE LEVELS. REGION 8731 PROVIDES A GOOD CHANCE FOR
ISOLATED M-CLASS FLARES. THERE IS ALSO A SLIGHT CHANCE FOR A MAJOR
FLARE FROM THIS REGION.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
GEOMAGNETIC FIELD ACTIVITY VARIED FROM QUIET TO MINOR STORM LEVELS
DUE TO CONTINUING CORONAL HOLE EFFECTS. THE GREATER THAN 2 MEV
ELECTRON FLUX REACHED HIGH LEVELS DURING THE PERIOD.
IIB. Geophysical Activity Forecast
GEOMAGNETIC FIELD ACTIVITY IS
EXPECTED TO VARY FROM UNSETTLED TO ACTIVE LEVELS DURING THE FIRST
DAY WITH A DECREASING TREND AS CORONAL HOLE EFFECTS GRADUALLY
SUBSIDE. QUIET TO UNSETTLED LEVELS ARE EXPECTED DURING THE LAST TWO
DAYS OF THE PERIOD. THE GREATER THAN 2 MEV ELECTRON FLUX IS EXPECTED
TO RANGE FROM MODERATE TO HIGH LEVELS THROUGHOUT THE PERIOD.
III. Event Probabilities 17 OCT to 19 OCT
| Class M | 60% | 60% | 60% |
| Class X | 10% | 10% | 10% |
| Proton | 10% | 10% | 10% |
| PCAF | YELLOW | ||
IV. Penticton 10.7 cm Flux
Observed 16 OCT 189 Predicted 30 DEC-16 OCT 185/185/180 90 Day Mean 16 OCT 158
V. Geomagnetic A Indices
OBSERVED AFR/AP 15 OCT 017/024 ESTIMATED AFR/AP 16 OCT 020/020 PREDICTED AFR/AP 17 OCT-19 OCT 015/015-012/010-010/010
VI. Geomagnetic Activity Probabilities 17 OCT to 19 OCT
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 15% | 10% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 20% | 15% |
| Minor storm | 15% | 15% | 05% |
| Major-severe storm | 10% | 05% | 01% |
All times in UTC
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