Viewing archive of Friday, 23 April 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 Apr 23 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 113 Issued at 2200Z on 23 APR 1999

IA. Analysis of Solar Active Regions and Activity from 22-2100Z to 23-2100Z

SOLAR ACTIVITY WAS VERY LOW. NO FURTHER DEVELOPMENT WAS OBSERVED IN REGION 8518 (S14W10) WHICH HAS NOW STABILIZED AS AN E-TYPE BETA GROUP. OCCASIONAL SURGING AND POINT BRIGHTENINGS WERE ALSO NOTED IN THIS REGION THROUGHOUT THE PERIOD. NEW REGION 8522 (N16E63) WAS NUMBERED TODAY. REMAINING REGIONS WERE QUIET.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE VERY LOW TO LOW. REGION 8518 APPEARS TO BE THE ONLY REGION CAPABLE OF C-CLASS ACTIVITY.
IIA. Geophysical Activity Summary 22-2100Z to 23-2100Z
THE GEOMAGNETIC FIELD WAS QUIET
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO REMAIN QUIET
III. Event Probabilities 24 APR to 26 APR
Class M05%05%05%
Class X01%01%01%
Proton01%01%01%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       23 APR 098
  Predicted   24 APR-26 APR  100/100/100
  90 Day Mean        23 APR 130
V. Geomagnetic A Indices
OBSERVED AFR/AP 22 APR  002/004
ESTIMATED AFR/AP 23 APR  006/007
PREDICTED AFR/AP 24 APR-26 APR  007/010-010/010-010/010
VI. Geomagnetic Activity Probabilities 24 APR to 26 APR
A. Middle Latitudes
Active10%15%15%
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Active15%20%20%
Minor storm05%05%05%
Major-severe storm01%01%01%

All times in UTC

<< Go to daily overview page

Latest news

Support SpaceWeatherLive.com!

A lot of people come to SpaceWeatherLive to follow the Sun's activity or if there is aurora to be seen, but with more traffic comes higher server costs. Consider a donation if you enjoy SpaceWeatherLive so we can keep the website online!

SpaceWeatherLive Pro
Support SpaceWeatherLive with our merchandise
Check out our merchandise

Latest alerts

Get instant alerts!

Space weather facts

Last X-flare2024/12/08X2.2
Last M-flare2024/12/24M1.1
Last geomagnetic storm2024/12/17Kp5+ (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
November 2024152.5 -13.9
December 2024110.7 -41.8
Last 30 days117.3 -41.4

This day in history*

Solar flares
12001M5
22024M4.7
32024M4.1
42023M2.9
52023M2.6
DstG
11995-65G1
22014-57
32001-55G1
42002-49G1
51990-47
*since 1994

Social networks