NOAA/USAF Report of Solar-Geophysical Activity 26 May 2000

Report of Solar-Geophysical Activity

:Issued: 2000 May 26 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 147 ISSUED AT 2200Z ON 26 MAY 2000

IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  25/2100Z

TO 26/2100Z:  SOLAR ACTIVITY WAS LOW. SEVERAL SMALL C-CLASS FLARES

OCCURRED IN A VARIETY OF REGIONS. REGION 9002 (N20W79) WAS THE MOST

ACTIVE AREA ON THE VISIBLE DISK.  NEW REGIONS 9018 (S20W11) AND 9019

(S34W38) EMERGED ON THE DISK.

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

TO MODERATE. C-CLASS ACTIVITY IS EXPECTED TO CONTINUE AND THERE IS A

CHANCE OF A LOW-LEVEL M-CLASS FLARE.

IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 25/2100Z TO 26/2100Z:

THE GEOMAGNETIC FIELD RANGED FROM QUIET TO MINOR STORM LEVELS.  THE

MOST DISTURBED PERIODS OCCURRED FROM 26/06-12UT. THE GREATER THAN 2

MEV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT WAS MODERATE TO HIGH.

IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS

EXPECTED TO BE QUIET TO UNSETTLED. INCREASED ACTIVITY LEVELS ARE

POSSIBLE BY THE END OF THE FORECAST PERIOD DUE TO WELL POSITIONED

CORONAL HOLES.

III.  EVENT PROBABILITIES 27 MAY-29 MAY

CLASS M    30/30/30

CLASS X    01/01/01

PROTON     01/01/01

PCAF       GREEN

IV.  PENTICTON 10.7 CM FLUX

OBSERVED           26 MAY 168

PREDICTED   27 MAY-29 MAY  160/150/145

90 DAY MEAN        26 MAY 196

V.  GEOMAGNETIC A INDICES

OBSERVED AFR/AP 25 MAY  023/031

ESTIMATED AFR/AP 26 MAY  020/023

PREDICTED AFR/AP 27 MAY-29 MAY  010/012-010/015-010/025

VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 27 MAY-29 MAY

A.  MIDDLE LATITUDES

ACTIVE                15/15/15

MINOR STORM           05/05/05

MAJOR-SEVERE STORM    01/01/01

B.  HIGH LATITUDES

ACTIVE                15/15/15

MINOR STORM           05/05/05

MAJOR-SEVERE STORM    05/05/05