Viewing archive of Sunday, 24 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 24 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 297 Issued at 2200Z on 24 OCT 1999IA. Analysis of Solar Active Regions and Activity from 23-2100Z to 24-2100Z SOLAR ACTIVITY WAS LOW. SMALL C-CLASS FLARES CONTINUED
BUT AT A LESS FREQUENT RATE THAN YESTERDAY. REGION 8741 (S26E36)
PRODUCED THE LARGEST REPORTED FLARE, A C2/SF AT 24/1606UT. GROWTH IN
THIS REGION HAS SLOWED. REGION 8739 (S12E16) CONTINUED TO DEVELOP
AND APPEARS TO HAVE FORMED A SMALL DELTA CONFIGURATION IN THE
CENTRAL SUNSPOTS.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. C-CLASS EVENTS ARE EXPECTED TO CONTINUE. M-CLASS FLARES
ARE POSSIBLE IN REGIONS 8739 AND 8741.
IIA. Geophysical Activity Summary 23-2100Z to 24-2100Z
THE GEOMAGNETIC FIELD RANGED IN ACTIVITY FROM QUIET TO MINOR STORM.
THE MOST DISTURBED PERIOD OCCURRED FROM 24/0600-0900UT. THE GREATER
THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT WAS MODERATE TO
HIGH.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY UNSETTLED TO ACTIVE FOR THE NEXT TWO DAYS
BECOMING QUIET TO UNSETTLED BY THE END OF THE FORECAST PERIOD.
III. Event Probabilities 25 OCT to 27 OCT
| Class M | 30% | 30% | 30% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 24 OCT 159 Predicted 25 OCT-27 OCT 160/155/150 90 Day Mean 24 OCT 158
V. Geomagnetic A Indices
OBSERVED AFR/AP 23 OCT 026/026 ESTIMATED AFR/AP 24 OCT 025/025 PREDICTED AFR/AP 25 OCT-27 OCT 020/020-015/015-010/012
VI. Geomagnetic Activity Probabilities 25 OCT to 27 OCT
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 20% |
| Minor storm | 15% | 15% | 10% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 25% |
| Minor storm | 20% | 20% | 20% |
| Major-severe storm | 15% | 15% | 10% |
All times in UTC
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