Viewing archive of Saturday, 26 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 26 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 177 Issued at 2200Z on 26 JUN 1999IA. Analysis of Solar Active Regions and Activity from 25-2100Z to 26-2100Z
SOLAR ACTIVITY WAS MODERATE. REGION 8598 (N23E02)
PRODUCED AN M2/2N AT 0512Z. THE GROUP CONTINUES TO BE THE DOMINANT
REGION ON THE DISK AND PRODUCED ADDITIONAL C-CLASS FLARES DURING THE
PAST 24 HOURS. REGION 8602 (N17E35) IS ALSO IMPRESSIVE LOOKING WITH
BRIGHT, FLUCTUATING PLAGE BUT COULD ONLY PRODUCE A SUBFLARE. REGION
8596 (N22W12) WAS ALSO ACTIVE A CONTRIBUTED A C4/1N FLARE AT 1650Z.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE. REGIONS 8598 AND 8602 ARE EXPECTED TO BE THE MAIN ACTIVITY
CENTERS FOR THE NEXT THREE DAYS. THERE IS A SLIGHT CHANCE FOR MAJOR
FLARE OR PROTON PRODUCING ACTIVITY FROM REGION 8598.
IIA. Geophysical Activity Summary 25-2100Z to 26-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE. A SHOCK WAS SEEN AT THE
ACE SPACECRAFT AT 0215Z AND WAS FOLLOWED BY A FEW HOURS OF
MODERATELY NEGATIVE SOUTHWARD INTERPLANETARY FIELD. A 16 NT SUDDEN
IMPULSE OCCURRED AT 0326Z AND WAS FOLLOWED BY A 12 HOUR PERIOD OF
UNSETTLED TO ACTIVE GEOMAGNETIC CONDITIONS. A SECOND SHOCK WAS SEEN
AT ACE AT 1925Z, FOLLOWED BY ANOTHER SUDDEN IMPULSE AT 2020Z
WHICH MEASURED 38 NT IN BOULDER. AS OF FORECAST FILE TIME THE
INTERPLANETARY MAGNETIC FIELD WAS ORIENTED NORTHWARDS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY UNSETTLED FOR THE NEXT TWO DAYS. HOWEVER, THE
NATURE OF THE PLASMA AND FIELDS BEHIND THE 20/1925Z SHOCK AT ACE IS
CURRENTLY UNKNOWN AND COULD BE GEOEFFECTIVE. THEREFORE THERE IS A
POSSIBILITY OF DISTURBED CONDITIONS FOR THE NEXT 12 HOURS. AN
INCREASE IN GEOMAGNETIC ACTIVITY IS ALSO POSSIBLE ON THE THIRD DAY
IN RESPONSE TO THE PARTIAL HALO CORONAL MASS EJECTION OF 24/1200Z.
III. Event Probabilities 27 JUN to 29 JUN
| Class M | 55% | 55% | 55% |
| Class X | 15% | 15% | 15% |
| Proton | 20% | 20% | 20% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 26 JUN 200 Predicted 27 JUN-29 JUN 205/205/205 90 Day Mean 26 JUN 141
V. Geomagnetic A Indices
OBSERVED AFR/AP 25 JUN 002/005 ESTIMATED AFR/AP 26 JUN 014/012 PREDICTED AFR/AP 27 JUN-29 JUN 010/012-010/012-015/010
VI. Geomagnetic Activity Probabilities 27 JUN to 29 JUN
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 30% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 35% |
| Minor storm | 10% | 10% | 15% |
| Major-severe storm | 01% | 01% | 10% |
All times in UTC
Currently there's no noteworthy space weather
Latest news
Friday, 28 March 2025
X1.1 solar flare
Monday, 24 March 2025
Coronal hole faces Earth
Saturday, 22 March 2025
Strong G3 geomagnetic storm watch for 23 March
Latest forum messages
2025/04/12-13 Filament CMEs 2025/04/16 G2 Watch 63AR4062 15AR 4055 100Incoming & Unnumbered Active Regions 1714AR 4060 24
More topicsSupport 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!
Latest alerts
10:39 UTC - Solar flare
Moderate M1.52 flare from sunspot region 4055
10:24 UTC - Radio Blackout
Minor R1 radio blackout in progress (≥M1 - current: M1.52)
Monday, 14 April 2025
23:15 UTC - Geomagnetic activity
Active geomagnetic conditions (Kp4) Threshold Reached: 23:01 UTC
07:09 UTC - Solar flare
Moderate M4.28 flare from sunspot region 4055
06:48 UTC - Radio Blackout
Minor R1 radio blackout in progress (≥M1 - current: M1.53)
Space weather facts
| Last X-flare | 2025/03/28 | X1.1 |
| Last M-flare | 2025/04/14 | M4.2 |
| Last geomagnetic storm | 2025/04/06 | Kp5 (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| March 2025 | 134.2 -20.4 |
| April 2025 | 128.8 -5.4 |
| Last 30 days | 129.1 -15.1 |