NOAA/USAF Report of Solar-Geophysical Activity 22 June 2000

Report of Solar-Geophysical Activity

:Issued: 2000 Jun 22 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 174 ISSUED AT 2200Z ON 22 JUN 2000

IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  21/2100Z

TO 22/2100Z:  SOLAR ACTIVITY HAS BEEN LOW. REGION 9042 (N23W54)

PRODUCED MOST OF TODAY’S C-CLASS EVENTS, INCLUDES THE LARGEST, A

C5/SF AT 0023Z. REGIONS 9040 (N18W73) AND 9046 (N20W21) ALSO

EXHIBITED SUBFLARE LEVEL BRIGHTENINGS DURING THE EVENT   REGION 9042

HAS CONTINUED TO DECAY, ESPECIALLY IN THE TRAILER PORTION OF THE

GROUP. REGION 9046 (N20W21) ALSO CONTRIBUTED A FEW C-CLASS EVENTS

AND HAS SHOWN A SLIGHT DECREASE IN AREA. NEW REGION 9057 (N14E72)

ROTATED INTO VIEW TODAY AS A SIMPLE H-TYPE REGION.

IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE

MOSTLY LOW, BUT THERE IS A CHANCE FOR AN ISOLATED M-CLASS EVENT

SOMETIME DURING THE NEXT THREE DAYS. REGIONS 9042 AND 9046 ARE

CONSIDERED TO BE THE MOST LIKELY SOURCES FOR M-CLASS FLARES.

IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 21/2100Z TO 22/2100Z:

THE GEOMAGNETIC FIELD RANGED FROM QUIET TO ACTIVE. QUIET TO UNSETTLED

LEVELS PREDOMINATED FOR MOST OF THE DAY, BUT THERE WAS ONE ACTIVE

PERIOD FROM 0000-0300Z. REAL-TIME SOLAR WIND OBSERVATIONS FROM THE

ACE SPACECRAFT INDICATED A SOLAR SECTOR BOUNDARY CROSSING FROM AN

‘AWAY’ (POSITIVE) CONFIGURATION TO A ‘TOWARDS’ (NEGATIVE)

CONFIGURATION BETWEEN 0100-1200Z.

IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS

EXPECTED TO BE MOST UNSETTLED TOMORROW, BUT GRADUAL INCREASE TO

UNSETTLED TO ACTIVE IS ANTICIPATED LATE TOMORROW OR BY THE SECOND

DAY. THE INCREASE IS EXPECTED AS A RESPONSE TO THE INFLUENCE OF A

RECURRENT CORONAL HOLE.

III.  EVENT PROBABILITIES 23 JUN-25 JUN

CLASS M    35/35/35

CLASS X    05/05/05

PROTON     05/05/05

PCAF       GREEN

IV.  PENTICTON 10.7 CM FLUX

OBSERVED           22 JUN 180

PREDICTED   23 JUN-25 JUN  175/175/170

90 DAY MEAN        22 JUN 186

V.  GEOMAGNETIC A INDICES

OBSERVED AFR/AP 21 JUN  006/008

ESTIMATED AFR/AP 22 JUN  012/012

PREDICTED AFR/AP 23 JUN-25 JUN  012/015-015/015-015/020

VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 23 JUN-25 JUN

A.  MIDDLE LATITUDES

ACTIVE                30/35/35

MINOR STORM           10/15/15

MAJOR-SEVERE STORM    05/05/05

B.  HIGH LATITUDES

ACTIVE                35/40/40

MINOR STORM           15/20/20

MAJOR-SEVERE STORM    05/10/10