NOAA/USAF Report of Solar-Geophysical Activity 25 May 2000
Report of Solar-Geophysical Activity
:Issued: 2000 May 25 2200 UT
# 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 146 ISSUED AT 2200Z ON 25 MAY 2000
IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 24/2100Z
TO 25/2100Z: SOLAR ACTIVITY WAS LOW. SEVERAL C-CLASS X-RAY EVENTS
OCCURRED DURING THE PERIOD WITH THE HIGHEST BEING A C9/SF AT
24/2117Z FROM REGION 9004 (N14W74). SOME MINOR DECAY WAS NOTED IN
REGION 9004 AS IT APPROACHES THE WEST LIMB. THE REST OF REGION 9017
(S15E68) ROTATED ONTO THE DISK AND IS NOW AN EHO BETA SUNSPOT GROUP
WITH APPROXIMATELY 6 SPOTS. NO NEW REGIONS WERE NUMBERED.
IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. THERE IS A POSSIBILITY OF AN ISOLATED M-CLASS EVENT
FROM REGION 9002 (N21W63), 9004, OR 9017.
IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 24/2100Z TO 25/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM QUIET TO MINOR STORM LEVELS. ONE
PERIOD OF MINOR STORM CONDITIONS WAS OBSERVED FROM 25/0300-0600Z.
THE SOLAR WIND VELOCITY SLOWLY DECREASED DURING THE PERIOD.
IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO ACTIVE DURING THE FIRST DAY, BECOMING QUIET
TO UNSETTLED ON DAYS TWO AND THREE.
III. EVENT PROBABILITIES 26 MAY-28 MAY
CLASS M 40/30/30
CLASS X 05/05/01
PROTON 01/01/01
PCAF GREEN
IV. PENTICTON 10.7 CM FLUX
OBSERVED 25 MAY 173
PREDICTED 26 MAY-28 MAY 165/160/150
90 DAY MEAN 25 MAY 196
V. GEOMAGNETIC A INDICES
OBSERVED AFR/AP 24 MAY 046/073
ESTIMATED AFR/AP 25 MAY 020/030
PREDICTED AFR/AP 26 MAY-28 MAY 010/010-010/010-010/012
VI. GEOMAGNETIC ACTIVITY PROBABILITIES 26 MAY-28 MAY
A. MIDDLE LATITUDES
ACTIVE 30/30/25
MINOR STORM 10/05/05
MAJOR-SEVERE STORM 01/01/01
B. HIGH LATITUDES
ACTIVE 40/35/35
MINOR STORM 20/10/10
MAJOR-SEVERE STORM 05/05/05
