Viewing archive of Saturday, 23 January 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 Jan 23 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 023 Issued at 2200Z on 23 JAN 1999IA. Analysis of Solar Active Regions and Activity from 22-2100Z to 23-2100Z SOLAR ACTIVITY WAS LOW. REGION 8439 (S23W70) PRODUCED
A C5/1N EVENT AT 23/1514Z. THE REGION ALSO PRODUCED NUMEROUS
SMALLER C-CLASS X-RAY EVENTS THROUGHOUT THE PERIOD. REGION 8439 AND
8440 (N19W63) SHOWED SOME SLIGHT DECAY. NO NEW REGIONS WERE
NUMBERED.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. AS REGIONS 8439 AND 8440 START APPROACHING THE WEST
LIMB, THEY ARE EACH STILL CAPABLE OF PRODUCING AN ISOLATED M-CLASS
EVENT.
IIA. Geophysical Activity Summary 22-2100Z to 23-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE DURING THE PERIOD. THE
GREATER THAN 10 MEV PROTONS PASSED THE 10 PFU THRESHOLD AT 23/1105Z,
AND REACHED A MAXIMUM OF 14 PFU AT 23/1130Z. SHORTLY THEREAFTER,
THE GREATER THAN 10 MEV PROTON FLUXES SLOWLY DECLINED BELOW EVENT
THRESHOLD AT 23/1245Z, BUT REMAINED ENHANCED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED WITH THE POSSIBILITY OF AN
ISOLATED ACTIVE PERIOD. THE GREATER THAN 10 MEV PROTONS ARE
EXPECTED TO REMAIN ENHANCED.
III. Event Probabilities 24 JAN to 26 JAN
| Class M | 50% | 40% | 20% |
| Class X | 10% | 10% | 05% |
| Proton | 05% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 23 JAN 166 Predicted 24 JAN-26 JAN 164/160/158 90 Day Mean 23 JAN 143
V. Geomagnetic A Indices
OBSERVED AFR/AP 22 JAN 007/010 ESTIMATED AFR/AP 23 JAN 014/012 PREDICTED AFR/AP 24 JAN-26 JAN 010/010-008/008-005/008
VI. Geomagnetic Activity Probabilities 24 JAN to 26 JAN
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 10% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 10% |
| Minor storm | 15% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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