NOAA SEC Report of Solar-Geophysical Activity – 21 Feb 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Feb 21 2210 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 052 Issued at 2200Z on 21 Feb 2002

IA.  Analysis of Solar Active Regions and Activity from  20/2100Z

to 21/2100Z:  Solar activity was moderate. Region 9825 (N13W90)

continued to be the region of primary concern as it rotated around

the NW limb. The three M-class flares this period all appear to have

originated from this region. The largest was an M3 at 21/1226Z. A

prominence erupted from this area at 21/0608Z, followed by a large

filament eruption at around 21/1100Z. Region 9335 (S09W75) grew

rather quickly this period and produced some small flares as it

approaches the west limb. New Regions 9838 (N05W18), 9839 (S16E06),

and 9840 (S12E72), were numbered today.

IB.  Solar Activity Forecast:  Solar activity is expected to continue

at moderate to high levels. We may continue to experience activity

from behind the NW limb for the next day or so. Region 9835 has

potential to produce M-class activity with a small chance for a

major flare.

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:

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

protons at geosynchronous orbit remain elevated following the small

proton event that began and ended between 20/0730 – 0800Z.

IIB.  Geophysical Activity Forecast:  The geomagnetic field  is

expected to continue at quiet to unsettled levels through day one.

Active conditions are expected on day two due to an expected CME

passage associated with the M5/1n flare that occurred on 20/0612Z.

Quiet to unsettled conditions are expected to return by day three.

III.  Event Probabilities 22 Feb-24 Feb

Class M    70/65/60

Class X    10/10/05

Proton     10/10/05

PCAF       yellow

IV.  Penticton 10.7 cm Flux

Observed           21 Feb 201

Predicted   22 Feb-24 Feb  205/200/200

90 Day Mean        21 Feb 223

V.  Geomagnetic A Indices

Observed Afr/Ap 20 Feb  006/008

Estimated Afr/Ap 21 Feb  008/008

Predicted Afr/Ap 22 Feb-24 Feb  010/015-015/020-010/010

VI.  Geomagnetic Activity Probabilities 22 Feb-24 Feb

A.  Middle Latitudes

Active                20/40/20

Minor storm           10/30/15

Major-severe storm    05/15/10

B.  High Latitudes

Active                25/50/25

Minor storm           15/35/20

Major-severe storm    10/15/10