NOAA SEC Report of Solar-Geophysical Activity 1 May 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 May 01 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 121 Issued at 2200Z on 01 May 2002

IA.  Analysis of Solar Active Regions and Activity from  30/2100Z

to 01/2100Z:  Solar activity was low. Several C-class subflares

occurred with most of them originating in new Region 9932 (S28E56).

So far this area appears to be a fairly small bipolar group just to

the northeast of Region 9927 (S30E43). Region 9926 (N14W29) has

grown since yesterday and has developed some mixed sunspot

polarities. It is just to the east of decaying Region 9919 (N13W40).

Newly numbered sunspot groups include 9930 (N12W17), 9931 (N15E19),

9932 (S28E56), 9933 (N16E64), and 9934 (S18E73). None appear to be

particularly large or complex.

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

to moderate. C-class and low-level M-class flares are possible from

a number of regions, including 9919, 9926, 9927, 9928, 9932, 9933,

and 9934.

IIA.  Geophysical Activity Summary 30/2100Z to 01/2100Z:

The geomagnetic field was quiet to unsettled. The greater than 10 MeV

proton flux was slightly enhanced (but remaining below the 10 pfu

event threshold) early on 01 May. The enhancement is believed to be

associated with a backside CME visible in LASCO observations.

IIB.  Geophysical Activity Forecast:  The geomagnetic field is

expected to be quiet to unsettled. The proton flux enhancement from

the backside CME is expected to slowly diminish to background

levels. Geomagnetic activity from this CME is not expected.

III.  Event Probabilities 02 May-04 May

Class M    30/40/50

Class X    01/01/05

Proton     01/01/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           01 May 162

Predicted   02 May-04 May  170/180/185

90 Day Mean        01 May 191

V.  Geomagnetic A Indices

Observed Afr/Ap 30 Apr  005/008

Estimated Afr/Ap 01 May  005/006

Predicted Afr/Ap 02 May-04 May  008/012-008/012-008/012

VI.  Geomagnetic Activity Probabilities 02 May-04 May

A.  Middle Latitudes

Active                15/15/15

Minor storm           05/05/05

Major-severe storm    01/01/01

B.  High Latitudes

Active                25/25/25

Minor storm           10/10/10

Major-severe storm    05/05/05