Viewing archive of Saturday, 24 July 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 Jul 24 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 205 Issued at 2200Z on 24 JUL 1999IA. Analysis of Solar Active Regions and Activity from 23-2100Z to 24-2100Z SOLAR ACTIVITY BECAME HIGH DUE TO THE OCCURRENCE OF
FIVE M-CLASS EVENTS. OPTICALLY UNCORRELATED M2 EVENTS OCCURRED AT
24/1112Z AND 24/1133Z. NEW REGION 8645 (S26E69) ROTATED ONTO THE
DISK AND PRODUCED AN M1/SF AT 23/2300Z, AN M1/1N AT 24/0404Z, AND A
LONG DURATION M3/SF AT 24/0756Z. WHILE STILL NOT FULLY VISIBLE, THIS
REGION SHOWED ITSELF AS A MODERATE SIZE D CLASS SUNSPOT GROUP. IT IS
VERY NEAR THE LOCATION OF OLD REGION 8611 THAT WAS ACTIVE LAST
ROTATION. REGION 8636 (N21W13) PRODUCED SEVERAL C-CLASS SUBFLARES.
OVERALL, THIS REGION WAS STABLE AND EXHIBITED MINOR MIXING OF
POLARITIES.
IB. Solar Activity Forecast
SOLAR ACTIVITY SHOULD CONTINUE AT A
MODERATE LEVEL. M-CLASS EVENTS ARE EXPECTED TO CONTINUE FROM REGION
8645 PRIMARILY DUE TO PERSISTENCE AND THE HISTORY OF THIS AREA.
REGION 8636 IS EXPECTED TO PRODUCE ONLY ISOLATED M-CLASS EVENTS.
THERE IS A SLIGHT POSSIBILITY OF MAJOR FLARES FROM THIS REGION AND
TO A LESSER DEGREE FROM REGION 8645.
IIA. Geophysical Activity Summary 23-2100Z to 24-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED. SOLAR WIND VELOCITY
REMAINED ELEVATED ABOVE NORMAL AND OCCASIONALLY EXCEEDED 500 KM/S.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO REMAIN QUIET TO UNSETTLED FOR THE NEXT THREE DAYS. NO
SIGNIFICANT CORONAL MASS EJECTIONS WERE OBSERVED WITH THE RECENT
ACTIVITY ON THE DISK AND EAST LIMB. THERE IS A SLIGHT POSSIBILITY OF
AN ENERGETIC PROTON EVENT SHOULD REGION 8636 PRODUCE A MAJOR FLARE.
III. Event Probabilities 25 JUL to 27 JUL
| Class M | 90% | 90% | 90% |
| Class X | 15% | 15% | 15% |
| Proton | 15% | 15% | 15% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 24 JUL 184 Predicted 25 JUL-27 JUL 186/189/190 90 Day Mean 24 JUL 156
V. Geomagnetic A Indices
OBSERVED AFR/AP 23 JUL 010/012 ESTIMATED AFR/AP 24 JUL 009/012 PREDICTED AFR/AP 25 JUL-27 JUL 010/012-008/010-008/008
VI. Geomagnetic Activity Probabilities 25 JUL to 27 JUL
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 05% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 05% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 10% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 05% | 01% | 01% |
All times in UTC
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