Viewing archive of Thursday, 21 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 21 2200 UTC
Prepared 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 1999

IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z

SOLAR ACTIVITY WAS VERY LOW. REGIONS 8439 (S22W42) AND 8440 (N19W37) CONTINUE TO HAVE PLAGE FLUCTUATIONS AND POINT BRIGHTENINGS. BOTH REGIONS MAINTAINED A BETA-GAMMA MAGNETIC CLASSIFICATION WITH APPROXIMATELY 25 SPOTS IN EACH REGION. NEW REGION 8446 (N14E61) APPEARED AS A BXO-BETA SPOT GROUP WITH 3 SPOTS.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW TO MODERATE. REGIONS 8439 AND 8440 ARE EACH CAPABLE OF PRODUCING AN ISOLATED M-CLASS EVENT. ANOTHER EVENT COULD OCCUR FROM THE REGION JUST BEHIND THE NORTHEAST LIMB, THE SITE OF YESTERDAY'S M5 X-RAY EVENT.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED. THE GREATER THAN 10 MEV PROTONS BECAME ENHANCED BUT BELOW EVENT THRESHOLD FROM YESTERDAY'S SOLAR ACTIVITY.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET TO UNSETTLED. THE GREATER THAN 10 MEV PROTONS ARE EXPECTED TO REMAIN ENHANCED FOR THE FIRST PART OF THE PERIOD.
III. Event Probabilities 22 JAN to 24 JAN
Class M60%50%50%
Class X10%10%10%
Proton05%01%01%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       21 JAN 175
  Predicted   22 JAN-24 JAN  180/185/180
  90 Day Mean        21 JAN 141
V. Geomagnetic A Indices
OBSERVED AFR/AP 20 JAN  008/007
ESTIMATED AFR/AP 21 JAN  010/012
PREDICTED AFR/AP 22 JAN-24 JAN  012/014-012/012-010/010
VI. Geomagnetic Activity Probabilities 22 JAN to 24 JAN
A. Middle Latitudes
Active25%20%15%
Minor storm05%05%01%
Major-severe storm01%01%01%
B. High Latitudes
Active30%25%20%
Minor storm10%10%05%
Major-severe storm01%01%01%

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