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

:Product: Report of Solar-Geophysical Activity

:Issued: 2000 Apr 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 110 ISSUED AT 2200Z ON 19 APR 2000

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

TO 19/2100Z:  SOLAR ACTIVITY WAS LOW.  THE LARGEST EVENT WAS A C5/SF

EVENT FROM NEW REGION 8967 (N20E66).  REGIONS 8963 (N16W04), AND

8959 (S15W62) PRODUCED SEVERAL MINOR C-CLASS EVENTS.  NEW REGIONS

8967, AND 8968 (S13E28) WERE NUMBERED TODAY.

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

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

THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE.  ONE PERIOD OF ISOLATED

ACTIVE CONDITIONS WAS OBSERVED FROM 19/1500-1800Z.

IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS

EXPECTED TO PREDOMINANTLY QUIET TO UNSETTLED WITH PERIODS OF

ISOLATED ACTIVE CONDITIONS POSSIBLE.

III.  EVENT PROBABILITIES 20 APR-22 APR

CLASS M    30/30/30

CLASS X    05/05/05

PROTON     01/01/01

PCAF       GREEN

IV.  PENTICTON 10.7 CM FLUX

OBSERVED           19 APR 168

PREDICTED   20 APR-22 APR  170/175/180

90 DAY MEAN        19 APR 183

V.  GEOMAGNETIC A INDICES

OBSERVED AFR/AP 18 APR  005/007

ESTIMATED AFR/AP 19 APR  010/012

PREDICTED AFR/AP 20 APR-22 APR  010/015-008/012-005/005

VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 20 APR-22 APR

A.  MIDDLE LATITUDES

ACTIVE                30/25/20

MINOR STORM           10/10/05

MAJOR-SEVERE STORM    01/01/01

B.  HIGH LATITUDES

ACTIVE                35/35/25

MINOR STORM           20/20/15

MAJOR-SEVERE STORM    05/05/01