Joint USAF/NOAA Report of Solar and Geophysical Activity 19 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 19 2200 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 079 Issued at 2200Z on 19 Mar 2012
IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity was low. Region 1432 (N22W68) produced a C1/Sf event at 19/1351Z while developing spots in an area that was
previously plage.
IB. Solar Activity Forecast: Solar activity is expected to be very low to low for the next two days (20-21 March) until Regions 1432 and 1435 (S26W62) exit the visible disk. Activity is expected to decrease to very low levels with a chance for C-class activity on day three (22 March).
IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z:
Geomagnetic field activity was at mostly quiet levels. An isolated period of active was observed for the 0300-0600Z synoptic period. The enhanced activity followed what appeared to be the 15 March
transient arrival at the ACE spacecraft around 19/0315Z. Total field strength rose to 7nT, Bz turned southward to -7nT, wind speeds reached up to 590 km/s, and temperature and density showed a slight
increase. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels throughout the period.
IIB. Geophysical Activity Forecast: Geomagnetic activity is expected to be at quiet to unsettled levels on 20 March. Activity is expected to decrease to mostly quiet levels for the rest of the period.
III. Event Probabilities 20 Mar-22 Mar
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 19 Mar 102
Predicted 20 Mar-22 Mar 100/100/100
90 Day Mean 19 Mar 123
V. Geomagnetic A Indices
Observed Afr/Ap 18 Mar 011/011
Estimated Afr/Ap 19 Mar 008/009
Predicted Afr/Ap 20 Mar-22 Mar 008/010-005/005-005/005
VI. Geomagnetic Activity Probabilities 20 Mar-22 Mar
A. Middle Latitudes
Active 15/05/10
Minor storm 05/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor storm 20/15/15
Major-severe storm 10/05/15
