Viewing archive of Monday, 11 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 11 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 284 Issued at 2200Z on 11 OCT 1999IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z
SOLAR ACTIVITY WAS LOW. TODAY'S ACTIVITY CONSISTED OF A
FEW, LOW LEVEL C-CLASS EVENTS. OF THE 10 SPOTTED REGIONS ON THE
DISK, NEW REGION 8731 (N10E62) WAS THE MOST ACTIVE WITH FREQUENT
POINT BRIGHTENINGS AND PLAGE FLUCTUATIONS. REGION 8728 (N22E38) IS
THE LARGEST GROUP ON THE DISK AT 560 MILLIONTHS AND SHOWS SOME
MAGNETIC COMPLEXITY. THIS GROUP HAS INCREASED SIGNIFICANTLY OVER THE
LAST 24 HOURS.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE
MOSTLY LOW, BUT THERE IS A GOOD CHANCE FOR AN ISOLATED M-CLASS EVENT
SOMETIME OVER THE NEXT THREE DAYS, ESPECIALLY GIVEN THE GROWTH AND
COMPLEXITY OF REGION 8728. REGION 8731 IS EXPECTED TO PRODUCE
OCCASIONAL C-CLASS FLARES OVER THE NEXT THREE DAYS.
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
THE GEOMAGNETIC FIELD WAS AT QUIET TO ACTIVE LEVELS DURING THE PAST
24 HOURS. ACTIVE LEVELS DOMINATED FROM 0000-1500Z. SOLAR WIND
MEASUREMENTS INDICATED THAT THE ACTIVITY WAS DUE TO A HIGH-SPEED,
LOW-DENSITY CORONAL HOLE ASSOCIATED SOLAR WIND STREAM. THE GREATER
THAN 2 MEV ELECTRONS ATTAINED HIGH FLUX VALUES DURING THE PAST 24
HOURS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED TO ACTIVE DURING THE NEXT 24 HOURS AS THE
CURRENT DISTURBANCE SUBSIDES. A NEW ENHANCEMENT IN GEOMAGNETIC
ACTIVITY IS EXPECTED ON THE 2ND AND 3RD DAYS AS A NEW SOLAR CORONAL
HOLE WILL BE ROTATING INTO A GEOEFFECTIVE POSITION. MID-LATITUDES
ARE FORECAST TO BE ACTIVE AND HIGH LATITUDES ARE EXPECTED TO BE AT
MINOR STORM LEVELS.
III. Event Probabilities 12 OCT to 14 OCT
| Class M | 35% | 35% | 35% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 11 OCT 167 Predicted 12 OCT-14 OCT 170/175/180 90 Day Mean 11 OCT 154
V. Geomagnetic A Indices
OBSERVED AFR/AP 10 OCT 018/028 ESTIMATED AFR/AP 11 OCT 020/022 PREDICTED AFR/AP 12 OCT-14 OCT 015/020-020/030-020/035
VI. Geomagnetic Activity Probabilities 12 OCT to 14 OCT
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 40% | 40% |
| Minor storm | 15% | 20% | 20% |
| Major-severe storm | 10% | 10% | 10% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 40% | 40% |
| Minor storm | 15% | 25% | 25% |
| Major-severe storm | 05% | 15% | 15% |
All times in UTC
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