Viewing archive of Friday, 16 July 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 Jul 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 197 Issued at 2200Z on 16 JUL 1999IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z
SOLAR ACTIVITY WAS MODERATE. REGION 8635 (N44W79)
PRODUCED A C7/SF FLARE AT 16/0849UT AND AN M3/0N FLARE AT 16/1550UT.
THE LATTER EVENT ALSO PRODUCED MINOR RADIO ACTIVITY, INCLUDING A
TYPE II SWEEP. REGION 8627 (S14W34) PRODUCED AN M1/SF AT 16/1731UT.
EIT IMAGERY FROM THE SOHO SPACE CRAFT SHOWED A POTENTIALLY ACTIVE
REGION JUST STATING TO ROTATE ONTO THE NORTHEAST LIMB. THIS COULD
POSSIBLY BE RETURNING REGION 8598. THAT PRODUCED SEVERAL C AND
M-CLASS EVENTS DURING THE LAST ROTATION. THE REST OF THE DISK AND
LIMBS WERE MOSTLY QUIET AND STABLE.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO CONTINUE
TO BE MODERATE. ISOLATED M-CLASS EVENTS CAN BE EXPECTED FROM REGIONS
8627 AND 8635.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
THE GEOMAGNETIC FIELD WAS QUIET.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY QUIET UNTIL THE LAST DAY OF THE PERIOD WHEN
UNSETTLED CONDITIONS CAN BE EXPECTED.
III. Event Probabilities 17 JUL to 19 JUL
| Class M | 50% | 50% | 50% |
| Class X | 05% | 05% | 05% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 16 JUL 132 Predicted 17 JUL-19 JUL 140/145/150 90 Day Mean 16 JUL 152
V. Geomagnetic A Indices
OBSERVED AFR/AP 15 JUL 008/010 ESTIMATED AFR/AP 16 JUL 005/005 PREDICTED AFR/AP 17 JUL-19 JUL 005/007-005/007-015/015
VI. Geomagnetic Activity Probabilities 17 JUL to 19 JUL
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 25% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 40% |
| Minor storm | 05% | 05% | 15% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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