:Product: 20000811RSGA.txt
:Issued: 2000 Aug 11 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Environment Center and the U.S. Air Force.
#
JOINT USAF/NOAA REPORT OF SOLAR AND GEOPHYSICAL ACTIVITY
SDF NUMBER 224 ISSUED AT 2200Z ON 11 AUG 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  10/2100Z
TO 11/2100Z:  SOLAR ACTIVITY WAS LOW. FREQUENT C-CLASS FLARES
OCCURRED, WITH FIVE REGIONS PARTICIPATING. REGION 9114 (N11W45) IS
STILL THE MOST IMPRESSIVE IN WHITE LIGHT AND H-ALPHA. NEWLY NUMBERED
REGIONS 9126 (N06W41) AND 9127 (S40E20) EACH HAD SUBFLARES. REGIONS
9124 (S14E52) AND 9125 (N25E55) WERE ACTIVE THROUGHOUT THE DAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY 10/2100Z TO 11/2100Z:
THE GEOMAGNETIC FIELD WAS AT UNSETTLED TO SEVERE STORM LEVELS. A
PROLONGED PERIOD OF STEADY SOUTHWARD IMF LASTING MORE THAN 24 HOURS
FUELED THE DISTURBANCE. THE BZ MAGNITUDE WAS NEARLY CONSTANT NEAR 10
NT. AT APPROXIMATELY 1800Z, A SHOCK PASSED ACE AND ENDED THE NEAR
STEADY-STATE OF THE SOLAR WIND. THE SOLAR WIND SPEED AND DENSITY
WERE QUITE AVERAGE PRIOR TO THE SHOCK, BUT ATTAINED VALUES NEAR 600
KM/S, AND 10 P/CC AFTER. THIS TRANSIENT MAY BE RELATED TO THE HALO
CME OF 09 AUGUST. A SATELLITE PROTON EVENT AT GREATER THAN 10 MEV
BEGAN AT 1650Z. THIS VERY SMALL EVENT REACHED A MAXIMUM OF 17 PFU AT
1655Z AND ENDED AT 1740Z. A SMALL PCA OF APPROXIMATELY 2.0 DB
OCCURRED AT THULE CONCURRENT WITH THE PROTON EVENT. THE SOLAR SOURCE
OF THE PARTICLES IS AS YET UNDETERMINED. THE GREATER THAN 2 MEV
ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT ATTAINED HIGH LEVELS LATE IN
THE PERIOD.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT ACTIVE TO MINOR STORM LEVELS FOR THE NEXT THREE
DAYS. EFFECTS FROM TODAY'S SHOCK, IN CONJUNCTION WITH THE
PRE-EXISTING AND STILL CONTINUING SOUTHWARD IMF, SHOULD FURTHER
EXTEND THE CURRENT DISTURBANCE. LOCAL NIGHTTIMES SHOULD SEE THE
PERIODS OF THE STRONGEST ACTIVITY.
III.  EVENT PROBABILITIES 12 AUG-14 AUG
CLASS M    30/30/30
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           11 AUG 187
PREDICTED   12 AUG-14 AUG  195/200/205
90 DAY MEAN        11 AUG 190
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 10 AUG  016/023
ESTIMATED AFR/AP 11 AUG  050/060
PREDICTED AFR/AP 12 AUG-14 AUG  020/025-020/020-020/020
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 12 AUG-14 AUG
A.  MIDDLE LATITUDES
ACTIVE                30/30/30
MINOR STORM           50/50/50
MAJOR-SEVERE STORM    10/10/10
B.  HIGH LATITUDES
ACTIVE                20/20/20
MINOR STORM           60/60/60
MAJOR-SEVERE STORM    15/15/15