Wednesday, March 14, 2012

Weekly Propagation Forecast Bulletins



Product: Weekly Highlights and Forecasts
:Issued: 2012 Mar 13 1539 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/weekly.html
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 05 - 11 March 2012

Solar activity ranged from low to high levels during the period. Activity was at high levels during 05 - 07 and 09 - 10 March due mostly to a series of long-duration major flares from Region 1429 (N18, L=301, class/area Dkc/1270 on 07 March) which included an X1/2b at 05/0409Z, an X5/3b at 07/0024Z, an M6 at 09/0353Z, and an M8 at 10/1744Z. All four flares were associated with Earth-directed CMEs. Region 1429 was large and magnetically complex during the period, exhibiting a beta-gamma-delta configuration with multiple deltas. It appeared to slowly decay during 09 - 10 March, but retained much of its magnetic complexity. Region 1430 (N20, L=315, class/area Dai/200 on 07 March) produced an X1/Sf at 07/0114Z during a period of rapid development. Region 1430 appeared to be in a gradual decay phase during 08 - 10 March.

The period began with a greater than 10 MeV proton enhancement in progress. This increase from normal backgrounds was associated with a long-duration M2/1n flare that occurred prior to the period and sourced from Region 1429. The flux enhancement continued until the onset of greater than 100 MeV and greater than 10 MeV events early on 07 March associated with the X5/3b flare at 07/0024Z. The greater than 100 MeV event began at 07/0405Z, reached a maximum of 69 pfu at 07/1525Z, and ended at 10/1650Z. Also, a greater than 10 MeV event
began at 07/0510Z, reached a maximum of 6530 pfu at 08/1115Z, and was in progress at the close of the period.

The greater than 2 MeV electron flux at geosynchronous orbit was at normal to high levels during 05 - 06 March. Flux readings were unreliable during 07 - 09 March due to proton contamination. Fluxes were at moderate to high levels on 10 and 11 March.

Geomagnetic field activity was at quiet to severe storm levels during the period. Quiet to unsettled levels occurred during 05 - 06 March with brief minor storm periods observed at high latitudes. Activity increased to unsettled to major storm levels on 07 March following a geomagnetic sudden impulse (SI) at 07/0427Z. The SI measured 20 nT at the Boulder magnetometer. This enhanced activity was due to a CME arrival associated with the X1/2b flare on 05 March. Quiet to minor storm levels occurred on 08 March, with major storm periods at high latitudes, as another CME, associated with the X5/3b on 07 March, impacted the geomagnetic field with an SI, as measured by the Boulder magnetometer of 59 nT, at 08/1105Z. Activity increased to quiet to severe storm levels on 09 March due to
sustained southward IMF Bz combined with increased IMF Bt as CME effects persisted. Activity decreased to quiet to minor storm levels with major storm periods at high latitudes on 10 March as CME effects gradually subsided. A return to quiet levels was observed on 11 March.

Forecast of Solar and Geomagnetic Activity 14 March - 09 April 2012

Solar activity is expected to be at low levels during 14 - 16 March with a chance for M-class activity from Region 1429. Activity is expected to decrease to predominantly background levels during 17 - 27 March, following the departure of Region 1429 on 15 March. An increase to low levels with a slight chance for M-class activity is expected from 28 March through the end of forecast period, as Region 1430 returns on 28 March and Region 1429 returns on 29 March.

A chance exists for another proton event from 14 - 16 March, as Region 1429, rotates off the visible disk. No events are expected until Region 1429 returns on 29 March, when a slight chance for another event from this proton producing region exists through the end of the forecast period.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at moderate to high levels during 14 - 19 March and 29 March - 03 April. Normal to moderate flux levels are expected during 20-28 March and 04 - 07 April.

Geomagnetic field activity is expected to be at predominantly quiet levels from 14 - 16 March. Activity is expected to increase to quiet to active levels during 17 - 18 March due to recurrent coronal hole high-speed stream effects. Activity is expected to decrease to mostly quiet levels during 19 - 27 March. Quiet to unsettled levels are expected during 28 - 31 March as another coronal hole high speed stream becomes geoeffective. A return to quiet levels is expected
from 01- 02 April. Another increase to quiet to unsettled levels is expected on 03 - 04 April as a coronal hole high speed stream becomes geoeffective. A return to predominantly quiet levels is
expected to prevail for the remainder of the period.

Issued: 2012 Mar 13 1539 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/wwire.html
#
# 27-day Space Weather Outlook Table
# Issued 2012-03-13
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2012 Mar 14 115 5 2
2012 Mar 15 110 5 2
2012 Mar 16 105 5 2
2012 Mar 17 105 15 3
2012 Mar 18 105 10 3
2012 Mar 19 105 5 2
2012 Mar 20 110 5 2
2012 Mar 21 110 5 2
2012 Mar 22 110 5 2
2012 Mar 23 110 5 2
2012 Mar 24 105 5 2
2012 Mar 25 105 5 2
2012 Mar 26 105 5 2
2012 Mar 27 105 5 2
2012 Mar 28 110 10 3
2012 Mar 29 115 8 3
2012 Mar 30 125 8 3
2012 Mar 31 130 8 3
2012 Apr 01 130 5 2
2012 Apr 02 130 5 2
2012 Apr 03 130 8 3
2012 Apr 04 130 8 3
2012 Apr 05 130 5 2
2012 Apr 06 125 5 2
2012 Apr 07 125 5 2
2012 Apr 08 125 5 2
2012 Apr 09 120 5 2
(NOAA)