Joint USAF/NOAA Report of Solar and Geophysical Activity 24 Apr 2009

Product: Report of Solar-Geophysical Activity

Issued: 2009 Apr 24 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 114 Issued at 2200Z on 24 Apr 2009

IA. Analysis of Solar Active Regions and Activity from 23/2100Z
to 24/2100Z: Solar activity was very low. No flares were detected.
The visible disk was spotless.

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

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z:
Geomagnetic field activity was at quiet levels. However, a sudden
impulse (SI) occurred at approximately 24/0050Z (10 nT, as measured
by the Boulder-NOAA magnetometer). There was no obvious source for
the SI.

IIB. Geophysical Activity Forecast: Geomagnetic field activity is
expected to be at quiet levels through the forecast period (25 – 27
Apr).

III. Event Probabilities 25 Apr-27 Apr
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 24 Apr 070
Predicted 25 Apr-27 Apr 070/070/070
90 Day Mean 24 Apr 070

V. Geomagnetic A Indices
Observed Afr/Ap 23 Apr 000/003
Estimated Afr/Ap 24 Apr 004/005
Predicted Afr/Ap 25 Apr-27 Apr 005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 25 Apr-27 Apr
A. Middle Latitudes
Active 05/05/05
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 10/05/05
Minor storm 01/01/01
Major-severe storm 01/01/01