NOAA/USAF Report of Solar-Geophysical Activity 28 June 2000

Report of Solar-Geophysical Activity

:Issued: 2000 Jun 28 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 180 ISSUED AT 2200Z ON 28 JUN 2000

IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  27/2100Z

TO 28/2100Z:  SOLAR ACTIVITY WAS LOW. THE LARGEST X-RAY EVENT THIS

PERIOD WAS A C6 FLARE, OBSERVED ON EIT IMAGERY NEAR THE SW LIMB AT

28/1219Z. A PROMINENCE ERUPTED ON THE NW LIMB NEAR NORTH 20,

RESULTING IN A LARGE CME WITH TYPE II SWEEP (SHOCK SPEED 536 KM/S)

AND A RATHER LONG DURATION C3 X-RAY BURST. BRIGHT SURGING WAS

EVIDENT ON THE NW LIMB SEVERAL HOURS PRIOR TO THIS ERUPTION.

REMAINING REGIONS WERE RELATIVELY QUIET.

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

TO MODERATE. MOSTLY LOW LEVEL C-CLASS FLARES ARE LIKELY WITH AN

ISOLATED CHANCE OF AN M-CLASS EVENT.

IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 27/2100Z TO 28/2100Z:

THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE. WEAK CORONAL HOLE EFFECTS

CONTINUED TODAY.

IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS

EXPECTED TO BE MOSTLY QUIET TO UNSETTLED WITH ISOLATED ACTIVE

PERIODS AT HIGH LATITUDES.

III.  EVENT PROBABILITIES 29 JUN-01 JUL

CLASS M    30/30/30

CLASS X    05/05/05

PROTON     01/01/01

PCAF       GREEN

IV.  PENTICTON 10.7 CM FLUX

OBSERVED           28 JUN 175

PREDICTED   29 JUN-01 JUL  175/175/180

90 DAY MEAN        28 JUN 184

V.  GEOMAGNETIC A INDICES

OBSERVED AFR/AP 27 JUN  014/018

ESTIMATED AFR/AP 28 JUN  008/015

PREDICTED AFR/AP 29 JUN-01 JUL  010/010-010/010-010/008

VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 29 JUN-01 JUL

A.  MIDDLE LATITUDES

ACTIVE                30/30/30

MINOR STORM           15/15/15

MAJOR-SEVERE STORM    01/05/05

B.  HIGH LATITUDES

ACTIVE                40/30/30

MINOR STORM           20/15/15

MAJOR-SEVERE STORM    10/05/05