Report of Solar-Geophysical Activity

Report of Solar-Geophysical Activity

Issued: 2008 Apr 07 2200 UTC

Prepared jointly by the U.S. Dept. of Commerce, NOAA,

Space Weather Prediction Center and the U.S. Air Force.

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 098 Issued at 2200Z on 07 Apr 2008

IA. Analysis of Solar Active Regions and Activity from 06/2100Z

to 07/2100Z: Solar activity was very low. No flares were observed

during the past 24 hours. No new regions were numbered.

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

low.

IIA. Geophysical Activity Summary 06/2100Z to 07/2100Z:

The geomagnetic field ranged from quiet to active conditions due to

the continued effects of the high speed stream. Solar wind

measurements from the ACE satellite ranged from 546 km/sec to 677

km/sec, and Bz varied from -4.9 nT to 5.1 nT throughout the period.

The 2 MeV electron flux at geosynchronous orbit reached high levels

during the past 24 hours.

IIB. Geophysical Activity Forecast: The geomagnetic filed is

expected to be quiet to unsettled with isolated active periods for

the next three days (08-10 April). Isolated minor storm conditions

are possible at high latitudes due the continued effects of the

coronal hole.

III. Event Probabilities 08 Apr-10 Apr

Class M 01/01/01

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 07 Apr 069

Predicted 08 Apr-10 Apr 070/070/070

90 Day Mean 07 Apr 072

V. Geomagnetic A Indices

Observed Afr/Ap 06 Apr 011/018

Estimated Afr/Ap 07 Apr 006/012

Predicted Afr/Ap 08 Apr-10 Apr 010/010-010/010-010/010

VI. Geomagnetic Activity Probabilities 08 Apr-10 Apr

A. Middle Latitudes

Active 25/25/25

Minor storm 05/05/05

Major-severe storm 01/01/01

B. High Latitudes

Active 35/35/35

Minor storm 10/10/10

Major-severe storm 05/05/05