Viewing archive of Wednesday, 21 January 1998
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 1998 Jan 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 021 Issued at 2200Z on 21 JAN 1998IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z SOLAR ACTIVITY BECAME VERY LOW. ONLY SMALL TO MID
B-CLASS FLARES WERE OBSERVED. A MODERATELY LARGE FILAMENT LOCATED
NEAR S57E19 FADED BETWEEN 21/0400-0603Z. THIS EVENT WAS ACCOMPANIED
BY A LONG DURATION ARCADE IN THE EUV AND A PARTIAL HALO CORONAL MASS
EJECTION. MOST OF THE HALO OF MATERIAL WAS VISIBLE AROUND THE SOUTH
POLE BUT SOME WAS SEEN INTO NORTHERN LATITUDES AND PRESUMABLY INTO
AND ABOVE THE ECLIPTIC PLANE.
IB. Solar Activity Forecast
SOLAR ACTIVITY SHOULD CONTINUE AT A
VERY LOW LEVEL FOR THE NEXT THREE DAYS.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
THE GEOMAGNETIC FIELD WAS PREDOMINANTLY QUIET TO UNSETTLED. BRIEF
ACTIVE CONDITIONS WERE OBSERVED FROM 21/0600-0900Z. NEAR THE END OF
THE REPORTING PERIOD, SOLAR WIND VELOCITIES DROPPED FROM
APPROXIMATELY 450 KM/S TO NEAR 350 KM/S.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD SHOULD BE
QUIET TO UNSETTLED FOR 22-23 JAN. UNSETTLED TO ACTIVE CONDITIONS ARE
EXPECTED EARLY ON 24 JAN IN RESPONSE TO THE HALO CME MENTIONED
ABOVE. BRIEF MINOR STORM PERIODS ARE POSSIBLE ON THAT DAY.
III. Event Probabilities 22 JAN to 24 JAN
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 21 JAN 091 Predicted 22 JAN-24 JAN 090/089/088 90 Day Mean 21 JAN 096
V. Geomagnetic A Indices
OBSERVED AFR/AP 20 JAN 008/011 ESTIMATED AFR/AP 21 JAN 008/010 PREDICTED AFR/AP 22 JAN-24 JAN 008/010-008/008-015/012
VI. Geomagnetic Activity Probabilities 22 JAN to 24 JAN
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 35% |
| Minor storm | 05% | 05% | 20% |
| Major-severe storm | 01% | 01% | 10% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 35% |
| Minor storm | 05% | 05% | 25% |
| Major-severe storm | 01% | 01% | 10% |
All times in UTC
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