NOAA/USAF Report of Solar-Geophysical Activity 19 June 2000

Report of Solar-Geophysical Activity

:Issued: 2000 Jun 19 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 171 ISSUED AT 2200Z ON 19 JUN 2000

IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  18/2100Z

TO 19/2100Z:  SOLAR ACTIVITY HAS BEEN LOW DURING THE PAST 24 HOURS.

TODAY’S ACTIVITY CONSISTED OF A FEW, LOW-LEVEL C-CLASS FLARES.

REGION 9042 (N23W11) WAS ONE OF THE MORE ACTIVE REGIONS ON THE SUN,

PRODUCING OCCASIONAL SUBFLARE ACTIVITY. REGION 9046 (N21E19) IS THE

LARGEST REGION ON THE DISK (570 MILLIONTHS), BUT COULD ONLY MUSTER

ONE SUBFLARE. A FILAMENT OF ABOUT 30 DEGREES LENGTH ERUPTED FROM THE

NORTHEAST PART OF THE DISK LATE ON THE 18TH. A CME WAS SUBSEQUENTLY

OBSERVED TO ENTER THE LASCO/C2 FIELD OF VIEW CLOSE TO THE NORTH

SOLAR POLE AT 18/2140Z. THE TRANSIENT DOES NOT APPEAR TO BE

EARTHBOUND.

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

TO MODERATE. REGIONS 9042 AND 9046 ARE THE MOST LIKELY SOURCES FOR

M-CLASS LEVEL ACTIVITY. THERE IS A SLIGHT CHANCE FOR A MAJOR FLARE

OR A PROTON PRODUCING FLARE.

IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 18/2100Z TO 19/2100Z:

THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED FOR THE PAST 24

HOURS.

IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS

EXPECTED TO BE QUIET TO UNSETTLED FOR THE NEXT THREE DAYS.

III.  EVENT PROBABILITIES 20 JUN-22 JUN

CLASS M    50/50/50

CLASS X    10/10/10

PROTON     10/10/10

PCAF       GREEN

IV.  PENTICTON 10.7 CM FLUX

OBSERVED           19 JUN 178

PREDICTED   20 JUN-22 JUN  180/180/180

90 DAY MEAN        19 JUN 187

V.  GEOMAGNETIC A INDICES

OBSERVED AFR/AP 18 JUN  010/011

ESTIMATED AFR/AP 19 JUN  007/010

PREDICTED AFR/AP 20 JUN-22 JUN  010/010-010/010-010/010

VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 20 JUN-22 JUN

A.  MIDDLE LATITUDES

ACTIVE                15/15/15

MINOR STORM           10/10/10

MAJOR-SEVERE STORM    01/01/01

B.  HIGH LATITUDES

ACTIVE                20/20/20

MINOR STORM           10/10/10

MAJOR-SEVERE STORM    05/05/05