Viewing archive of Monday, 21 June 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 Jun 21 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 172 Issued at 2200Z on 21 JUN 1999

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

SOLAR ACTIVITY WAS LOW. THE PERIOD WAS CHARACTERIZED BY A NUMBER OF SMALL C-CLASS X-RAY FLARES, THE LARGEST BEING A C3/SF FROM REGION 8585 (N38W31). OTHER FLARING REGIONS INCLUDE 8594 (N14E67) AND 8583 (S11W64). AS REGION 8592 (N22E45) CONTINUED TO ROTATE ONTO THE DISK, OBSERVERS WERE BETTER ABLE TO DISTINGUISH SEPARATE MAGNETIC GROUPS; THEY WERE NUMBERED AS REGIONS 8596 (N23E53), 8597 (N22E63), AND 8598 (N26E69). ALSO NUMBERED TODAY WERE REGIONS 8595 (N26E18) AND 8599 (S16E77).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE AT LOW TO MODERATE LEVELS FOR THE NEXT THREE DAYS.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
THE GEOMAGNETIC FIELD WAS AT QUIET LEVELS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO REMAIN QUIET FOR THE FIRST TWO DAYS OF THE PERIOD. BY DAY THREE A RECURRENT SOUTHERN CORONAL HOLE IS FORECAST TO INCREASE THE FIELD TO UNSETTLED CONDITIONS.
III. Event Probabilities 22 JUN to 24 JUN
Class M40%40%40%
Class X05%05%05%
Proton10%10%10%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       21 JUN 146
  Predicted   22 JUN-24 JUN  150/155/160
  90 Day Mean        21 JUN 137
V. Geomagnetic A Indices
OBSERVED AFR/AP 20 JUN  002/004
ESTIMATED AFR/AP 21 JUN  004/005
PREDICTED AFR/AP 22 JUN-24 JUN  005/005-005/005-010/010
VI. Geomagnetic Activity Probabilities 22 JUN to 24 JUN
A. Middle Latitudes
Active10%10%20%
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Active15%15%25%
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-flare2024/12/22M1.1
Last geomagnetic storm2024/12/17Kp5+ (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
November 2024152.5 -13.9
December 2024103.3 -49.2
Last 30 days114 -43.9

This day in history*

Solar flares
12015M6.75
21998M3.34
32013M2.36
42013M1.97
52001M1.69
DstG
12002-67
22000-62G2
31989-60
42014-57
51982-53G1
*since 1994

Social networks