eekuasepinniW Posted February 18, 2011 Share Posted February 18, 2011 It's underperforming because the Bz is strongly positive (north pointing) which is the wrong polarity for a Gemag storm. Should it swing negative (south pointing) we could get storming but at this point in time I don't expect much more than a G2 event which would mean aurbo only along the northern Border States unless we got a strong substorm. Steve I'm aware of how the Bz works. You have to admit this is pretty disappointing for an X-class event with full halo. I became quite the aurora snob after closely following things from 2001-2004. I really only get excited when I see something like this coming at us at >2000km/s Link to comment Share on other sites More sharing options...
aslkahuna Posted February 18, 2011 Author Share Posted February 18, 2011 I'm aware of how the Bz works. You have to admit this is pretty disappointing for an X-class event with full halo. I became quite the aurora snob after closely following things from 2001-2004. I really only get excited when I see something like this coming at us at >2000km/s Ah yes the big groups of October 2003. They punched out a lot of flares with the finale being the X44. I managed to see part of a lot of them and most of the last one. Looking at the latitude of region 1158 (S21) we might have a problem with Sun-Earth Geometry which isn't all that favorable in the Winter with the result that the main thrust of the CME missed us and went below the ecliptic plane. That said, however, there has been an increase in the H and Z deflections on the Gakona magnetometer trace which could mean a shift in the Bz. I've been an aurora snob ever since I first saw one from San Jose CA in 1957. Steve Link to comment Share on other sites More sharing options...
aslkahuna Posted February 18, 2011 Author Share Posted February 18, 2011 The latest hourly report of the 3 hour ap/Kp index from the Air Force network is 32/4+ respectively which is barely minor storm. The Bz is less positive now but the Bt remains high enough that a strong southward shift in the Bz could result in significant storming. The Gakona magnetometer trace shows stronger deflections now. I will wait for more data but suspect that I will go with an alert for the Northern tier of states only. Steve Link to comment Share on other sites More sharing options...
aslkahuna Posted February 18, 2011 Author Share Posted February 18, 2011 The Bz is nearly zero while the Bt remains relatively high. The auroral oval display on Spaceweather.com shows and expansion of the oval indicating that substorming may be developing. With the possibility of the shift to a southward pointing component of the Interplanetary field, we are going with an Aurora Alert for the northern tier of states. Although substorming could develop beyond the G2 level, bright moonlight will make any aurora anywhere difficult to see. Steve Link to comment Share on other sites More sharing options...
aslkahuna Posted February 19, 2011 Author Share Posted February 19, 2011 It's all over. Incidentally, the X2 flare was neither huge nor a Mega as characterized in the media. There was a M6.6 in region 1161 today but no CME was observed. Steve Link to comment Share on other sites More sharing options...
wall_cloud Posted February 19, 2011 Share Posted February 19, 2011 never lived farther north than I-40 so I've never seen one. That is one of those things I'll eventually need to observe (along with an earthquake) Link to comment Share on other sites More sharing options...
aslkahuna Posted February 19, 2011 Author Share Posted February 19, 2011 never lived farther north than I-40 so I've never seen one. That is one of those things I'll eventually need to observe (along with an earthquake) They've been seen south of I-40-in fact, south of I-10 and even south of the Border (Down Mexico Way) but are relatively infrequent. As far as earthquakes are concerned just hope that the one you feel is a 4.0 or less. Steve Link to comment Share on other sites More sharing options...
bowtie` Posted February 20, 2011 Share Posted February 20, 2011 Steve, is this a sign that the Sun is coming out of this long minimum period? Better chances of these types of events in the coming future? I have very little knowledge of solar activity. Link to comment Share on other sites More sharing options...
aslkahuna Posted February 20, 2011 Author Share Posted February 20, 2011 As I mentioned in an earlier post in the thread about the M6.6 event, X-class flares begin to appear about two years after min so in that respect we're on schedule. The intensity of flares doesn't relate to the intensity of the cycle though their frequency does. Regardless of how this cycle goes there will be additional X-class events. Superimposed upon the the overall cycle is a 180 day one of peaks and lulls of which we are obviously in a peak of. Thus, although the cycle as a whole may top out at a smoothed R number of around 60, it's not impossible to have peaks around 100 or so. Finally, it should be noted that the Carrington event of 1859 occurred during a very low cycle. Cycle 20 while lower than cycles 19 and 21 featured some very strong events as well. Steve Link to comment Share on other sites More sharing options...
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