NOAA/USAF Report of Solar-Geophysical Activity 14 May 2000

Report of Solar-Geophysical Activity

:Issued: 2000 May 14 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 135 ISSUED AT 2200Z ON 14 MAY 2000

IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  13/2100Z

TO 14/2100Z:  SOLAR ACTIVITY WAS MODERATE. REGION 8993 (S23W58) WAS

THE MOST ACTIVE GROUP TODAY, PRODUCING AN M1/SF AT 0805Z, AS WELL AS

ADDITIONAL, UPPER-LEVEL C-CLASS EVENTS. THE REGION SHOWED SOME

GROWTH IN THE TRAILING PART OF THE REGION. REGION 8996 (S21E44) IS

THE LARGEST GROUP ON THE DISK WITH 1140 MILLIONTHS AREA, AND WAS

ABLE TO MUSTER A COUPLE UPPER-LEVEL C-CLASS EVENTS. REGION 8998

(S13E54) SHOWED SOME GROWTH TODAY, AND ALSO PRODUCED A C-CLASS

EVENT. NEW REGION 9002 (N18E76) ROTATED INTO VIEW TODAY AS A LARGE,

H-TYPE SUNSPOT: THE TRAILING PORTION OF THE REGION MAY BECOME

APPARENT OVER THE NEXT 24 HOURS. A LONG DURATION C-CLASS EVENT

OCCURRED FROM 13/2301 TO 14/0020Z. THIS EVENT WAS ASSOCIATED WITH A

FILAMENT DISAPPEARANCE IN THE NORTHEAST QUADRANT AND A CORONAL MASS

EJECTION WHICH BECAME VISIBLE IN THE LASCO C2 FIELD OF VIEW AT

0026Z. THE MASS EJECTION DOES NOT APPEAR TO BE EARTHWARD DIRECTED.

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

MODERATE OVER THE NEXT THREE DAYS, WITH REGIONS 8993 AND 8996 BEING

THE MOST LIKELY SOURCES FOR M-CLASS FLARES, ALTHOUGH 8989 (N16W54)

AND 8998 COULD ALSO CONTRIBUTE. THERE IS A SLIGHT CHANCE FOR A MAJOR

FLARE DURING THE NEXT 72 HOURS.

IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 13/2100Z TO 14/2100Z:

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

TO UNSETTLED LEVELS DOMINATED FOR MOST OF THE DAY, BUT A PERIOD OF

ENHANCED ACTIVITY (ACTIVE TO MINOR STORM) WAS OBSERVED BETWEEN

0000-0300Z. THERE WAS NO CLEAR-CUT SOLAR WIND SIGNATURE TO ACCOUNT

FOR THE SUBSTORM, OTHER THAN TWO HOURS OF MODERATELY ENHANCED

NEGATIVE BZ FROM 0000-0200Z.

IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS

EXPECTED TO BE MOSTLY UNSETTLED OVER THE NEXT THREE DAYS.

III.  EVENT PROBABILITIES 15 MAY-17 MAY

CLASS M    65/65/65

CLASS X    15/15/15

PROTON     05/05/10

PCAF       GREEN

IV.  PENTICTON 10.7 CM FLUX

OBSERVED           14 MAY 233

PREDICTED   15 MAY-17 MAY  235/235/240

90 DAY MEAN        14 MAY 188

V.  GEOMAGNETIC A INDICES

OBSERVED AFR/AP 13 MAY  015/015

ESTIMATED AFR/AP 14 MAY  015/013

PREDICTED AFR/AP 15 MAY-17 MAY  008/010-010/012-008/010

VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 15 MAY-17 MAY

A.  MIDDLE LATITUDES

ACTIVE                20/20/20

MINOR STORM           10/10/10

MAJOR-SEVERE STORM    05/05/05

B.  HIGH LATITUDES

ACTIVE                25/25/25

MINOR STORM           15/15/15

MAJOR-SEVERE STORM    05/05/05