Joint USAF/NOAA Report of Solar and Geophysical Activity 27 March 2012

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.
Updated 2012 Mar 27 2200 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 087 Issued at 2200Z on 27 Mar 2012

IA. Analysis of Solar Active Regions and Activity from 26/2100Z
to 27/2100Z: Solar activity has been at low levels. Region 1444
(N21W17) produced a C5/1f flare at 27/0308Z. Region 1442 (N12W13)
produced a C2 flare at 26/2338Z and a C1/Sf flare at 27/0430Z. SOHO
LASCO observed a full asymmetric halo CME at 26/2312Z which was
associated with Type II & Type IV radio sweeps. This CME was
determined to be a backsided event and should not be geoeffective.

IB. Solar Activity Forecast: Solar activity is expected to be low
with a chance for an isolated M-class flare. Old Region 1429 (N19,
L=299) is expected to return to the solar disk midday on 29 March,
which should increase M-class flare probabilities. New Region 1447
(S25W55) was numbered today and is a small C-type spot group.

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z:
The geomagnetic field was at quiet to unsettled levels. ACE data
indicate a solar sector boundary crossing during the period.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels for 28 March to 29
March, due to a favorably positioned negative polarity coronal hole.
Quiet levels are expected on the third day (30 March).

III. Event Probabilities 28 Mar-30 Mar
Class M 30/35/40
Class X 05/05/05
Proton 05/05/05
PCAF Green

IV. Penticton 10.7 cm Flux
Observed 27 Mar 106
Predicted 28 Mar-30 Mar 110/120/120
90 Day Mean 27 Mar 120

V. Geomagnetic A Indices
Observed Afr/Ap 26 Mar 004/003
Estimated Afr/Ap 27 Mar 009/012
Predicted Afr/Ap 28 Mar-30 Mar 013/015-007/010-006/005

VI. Geomagnetic Activity Probabilities 28 Mar-30 Mar
A. Middle Latitudes
Active 30/25/05
Minor storm 15/05/01
Major-severe storm 05/01/01
B. High Latitudes
Active 15/15/15
Minor storm 30/35/15
Major-severe storm 50/30/05