NOAA SEC Report of Solar-Geophysical Activity 29 Apr 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Apr 29 2210 UTC

# 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 119 Issued at 2200Z on 29 Apr 2002

IA.  Analysis of Solar Active Regions and Activity from  28/2100Z

to 29/2100Z:  Solar activity was low. Several low, optically

uncorrelated C-class flares were observed, the largest being a C4 at

29/0940Z. The likely sources for most of the discrete X-ray bursts

were Regions 9915 (N12W53) and 9919 (N15W13). No appreciable changes

were noted in these or the remaining active regions on the visible

disk. The overall enhanced X-ray baseline is likely due to the

return of several active regions on or near the east limb.

Considerable CME activity was noted off the east limb over the past

24 hours. New Regions 9927 (S28E68), and 9928 (N18E75) were numbered

today.

IB.  Solar Activity Forecast:  Solar activity is expected to be low.

Continued C-class flares are likely from Regions 9915 and 9919. The

potential for activity at or near the east limb will increase over

the coming days.

IIA.  Geophysical Activity Summary 28/2100Z to 29/2100Z:

The geomagnetic field was quiet to unsettled with isolated active

periods at high latitudes. The disturbed conditions are due to a

high speed coronal hole stream that began on the 27th.

IIB.  Geophysical Activity Forecast:  The geomagnetic field is expect

to continue at quiet to unsettled levels with isolated active

periods at high latitudes.

III.  Event Probabilities 30 Apr-02 May

Class M    15/20/30

Class X    01/05/05

Proton     01/01/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           29 Apr 153

Predicted   30 Apr-02 May  155/160/165

90 Day Mean        29 Apr 193

V.  Geomagnetic A Indices

Observed Afr/Ap 28 Apr  014/019

Estimated Afr/Ap 29 Apr  008/012

Predicted Afr/Ap 30 Apr-02 May  008/010-005/008-008/012

VI.  Geomagnetic Activity Probabilities 30 Apr-02 May

A.  Middle Latitudes

Active                30/25/30

Minor storm           10/05/10

Major-severe storm    05/01/05

B.  High Latitudes

Active                40/30/40

Minor storm           15/05/15

Major-severe storm    05/01/05