aslkahuna Posted July 13, 2012 Share Posted July 13, 2012 I read the article hence my response. One thing, to quibble about timing issues when the models used have an error factor of ± 7 hours is nonsensical. As I said, NASA tends to be feitier and more flamboyant in their descriptions of events than SWPC-perhaps it's because they have to be more into PR. Given the uncertainties involving the incoming CME, a more conservative approach is dictated. Also remember that a G2 Gemag is K=6 which covers 3 hour ap values up to 100 which can place visible aurbo into Ohio. Steve Link to comment Share on other sites More sharing options...
aslkahuna Posted July 13, 2012 Share Posted July 13, 2012 Another point involves the terminology used for the INTENSITY of a gemag and the CATEGORY as well as the indices used to determine each. As everyone knows a hurricane with an INTENSITY of 100 kt or greater is called a major hurricane but can have a CATEGORY of 3,4,or5. A similar situation exists for gemags. A gemag storm that reaches a maximum 3 hr ap value of 100 or more is referred to as a severe storm. Thus the intensity rating covers a K index value of 6+ to 9+ which high Category 2 through 5 for the gemag event. To add to the confusion, a G2 is a moderate storm, G3 strong, G4 severe, G5 extreme-also SWPC uses a USGS magnetometer network while I use the USAF network which because of more high latitude stations tends to give higher ap/K values while another site I visit uses the data from the Potsdam WDC which has different values still. Steve Link to comment Share on other sites More sharing options...
Carvers Gap Posted July 14, 2012 Share Posted July 14, 2012 Another point involves the terminology used for the INTENSITY of a gemag and the CATEGORY as well as the indices used to determine each. As everyone knows a hurricane with an INTENSITY of 100 kt or greater is called a major hurricane but can have a CATEGORY of 3,4,or5. A similar situation exists for gemags. A gemag storm that reaches a maximum 3 hr ap value of 100 or more is referred to as a severe storm. Thus the intensity rating covers a K index value of 6+ to 9+ which high Category 2 through 5 for the gemag event. To add to the confusion, a G2 is a moderate storm, G3 strong, G4 severe, G5 extreme-also SWPC uses a USGS magnetometer network while I use the USAF network which because of more high latitude stations tends to give higher ap/K values while another site I visit uses the data from the Potsdam WDC which has different values still. Steve So, NOAA is more reliable I am guessing. Based on this thread it appears it was strong, but not extreme. Taking some time to learn about these so thanks for the input. You think any effects will be noticed at all? Link to comment Share on other sites More sharing options...
aslkahuna Posted July 14, 2012 Share Posted July 14, 2012 So, NOAA is more reliable I am guessing. Based on this thread it appears it was strong, but not extreme. Taking some time to learn about these so thanks for the input. You think any effects will be noticed at all? Here's where the uncertainty comes in-we won't know the critical information on the CME until it reaches the Spacecraft out at 1 million miles sunward of us or about 40 minutes at best before it reaches us. Actual effects will depend upon the characteristics of the shock front and the following portions of the CME and (most importantly) the polarity of the imbedded magnetic field which needs to have Z (N-S pointing) component that must be negative or southward pointing to have maximum effect. A strong shock front plus a a strong total field and strongly negative Bz could bounce us up to a G4 storm in no time while a positive Bz would barely cause anything. In terms of the flare, it was a strong event but no where near extreme-that label is reserved for the X10+ flares. CMEs are different animals and often bear no direct relationship to flare intensity-in fact many of them come not from flares but from erupting filaments which may have only small X-Ray signatures. The biggest auroral show so far this cycle was a result of a CME from a modest X-Ray event. Of course when it comes to aurorae it's best to have the gemag storm occur at night. Bottom line-there will be some effects but one can only guess at what they will be and given that uncertainty one is bound to have disparate ideas of how strong of an effect. Steve Link to comment Share on other sites More sharing options...
LMolineuxLM1 Posted July 14, 2012 Share Posted July 14, 2012 Not sure If this is linked but we just had 3 quick power failures in 20 minutes time here. Link to comment Share on other sites More sharing options...
aurora Posted July 14, 2012 Share Posted July 14, 2012 The Bz parameter (tilt of the magnetosphere) is starting to wobble north and south, so the effects of the CME probably aren't far off now, although the solar wind velocity and density variables have not shown any significant increases thus far. Link to comment Share on other sites More sharing options...
Carvers Gap Posted July 14, 2012 Share Posted July 14, 2012 Capital Weather has updated their article substantially. Response from NASA w a nod to NOAA. Any updates on the event? Link to comment Share on other sites More sharing options...
QVectorman Posted July 14, 2012 Share Posted July 14, 2012 Appears its arrival is not to far off...Kp values are on the rise Link to comment Share on other sites More sharing options...
ChrisM Posted July 14, 2012 Share Posted July 14, 2012 aslkahuna, your posts in here are awesome. Thanks man. Link to comment Share on other sites More sharing options...
turtlehurricane Posted July 14, 2012 Share Posted July 14, 2012 It might finally be here? Link to comment Share on other sites More sharing options...
aurora Posted July 14, 2012 Share Posted July 14, 2012 Bz is tanking and velocity over 600 m/s...here we go. Link to comment Share on other sites More sharing options...
Kmlwx Posted July 14, 2012 Share Posted July 14, 2012 With Bz negative that would mean a larger impact correct? Link to comment Share on other sites More sharing options...
aurora Posted July 14, 2012 Share Posted July 14, 2012 With Bz negative that would mean a larger impact correct? A negative Bz means that the magnetic field is tilted south, which is good for the Northern Hemisphere. It's currently wobbling back and forth, but the general trend over the last hour has been more negative, which is good news. http://www.spacew.com/plots.php Link to comment Share on other sites More sharing options...
Kmlwx Posted July 14, 2012 Share Posted July 14, 2012 A negative Bz means that the magnetic field is tilted south, which is good for the Northern Hemisphere. It's currently wobbling back and forth, but the general trend over the last hour has been more negative, which is good news. http://www.spacew.com/plots.php Thanks for info Link to comment Share on other sites More sharing options...
mike2010 Posted July 14, 2012 Author Share Posted July 14, 2012 http://mms.rice.edu/.../justdials.html ^ real time dial icons Link to comment Share on other sites More sharing options...
Kmlwx Posted July 14, 2012 Share Posted July 14, 2012 Bz just spiked positive. Otherwise, the magnetometer seems to indicate the CME has arrived. Link to comment Share on other sites More sharing options...
heavy_wx Posted July 14, 2012 Share Posted July 14, 2012 Space Weather Message Code: WARK06 Serial Number: 199 Issue Time: 2012 Jul 14 1914 UTC WARNING: Geomagnetic K-Index of 6 expected Valid From: 2012 Jul 14 1915 UTC Valid To: 2012 Jul 14 2359 UTC Warning Condition: Onset NOAA Scale: G2 - Moderate Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude. Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms. Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible. Radio - HF (high frequency) radio propagation can fade at higher latitudes. Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state. Link to comment Share on other sites More sharing options...
aslkahuna Posted July 14, 2012 Share Posted July 14, 2012 Latest USAF magnetometer summary shows a 3 hr ap of 56 wit a K=5+ or high end G1 Category while the intensity is major storm. Steve Link to comment Share on other sites More sharing options...
Kmlwx Posted July 14, 2012 Share Posted July 14, 2012 Latest USAF magnetometer summary shows a 3 hr ap of 56 wit a K=5+ or high end G1 Category while the intensity is major storm. Steve Darn, only G1? Echoing the thanks of the other posters! Your info has been excellent! Link to comment Share on other sites More sharing options...
earthlight Posted July 14, 2012 Share Posted July 14, 2012 Velocity was 635 m/s a minute ago and the bz is dropping again now at -11.9 but still fluctuating. Link to comment Share on other sites More sharing options...
turtlehurricane Posted July 14, 2012 Share Posted July 14, 2012 Kp up over 5, need a bit more for good US action but we got hours yet. http://www.swpc.noaa.gov/wingkp/wingkp_15m_24h.gif Link to comment Share on other sites More sharing options...
aslkahuna Posted July 14, 2012 Share Posted July 14, 2012 The HAARP magnetometers are not showing strong flucuations yet, but the Riometer is showing 1-2 dB of absorption at 30MHz which means that Polar and auroral HF propagation is none too good right now-over the pole GPS signal paths may have some problems. Steve Link to comment Share on other sites More sharing options...
mike2010 Posted July 14, 2012 Author Share Posted July 14, 2012 NOAA Scale: G2 - Moderate Looks like NOAA is leaning towards NASA. nam vs. gfs.. ? the lack of severe wx must be gettin to me.. EDIT : SpaceWeather update - CME IMPACT: As expected, a CME hit Earth's magnetic field on July 14th at approximately 1800 UT or 11 am Pacific Daylight Time). A geomagnetic storm is brewing in the wake of the impact. At the moment, conditions appear favorable for auroras over high-latitude places such as Canada, Scandinavia, Antarctica and Siberia. It is too early to say whether the storm will intensify and bring auroras to middle latitudes as well. Stay tuned for updates Link to comment Share on other sites More sharing options...
aslkahuna Posted July 14, 2012 Share Posted July 14, 2012 Latest USAF magnetometer summary shows a 3 hr ap of 80 and a K=6z so we are in G2 territory based on that but the BOU magnetometer has only a K=5 or G1 and that's the official designation. Steve Link to comment Share on other sites More sharing options...
turtlehurricane Posted July 14, 2012 Share Posted July 14, 2012 Kp between 7 and 8, if this keeps up until sunset things could get very interesting. http://www.swpc.noaa.gov/wingkp/wingkp_15m_24h.gif Link to comment Share on other sites More sharing options...
eyewall Posted July 14, 2012 Share Posted July 14, 2012 Hopefully it lasts through the evening for those up north to get a good show. Link to comment Share on other sites More sharing options...
eyewall Posted July 14, 2012 Share Posted July 14, 2012 Bz is +10 which is no good (very north) Link to comment Share on other sites More sharing options...
aslkahuna Posted July 14, 2012 Share Posted July 14, 2012 The Kp has dropped to 5- barely G1 as the Bz has gone sharply nortward. Steve Link to comment Share on other sites More sharing options...
eyewall Posted July 15, 2012 Share Posted July 15, 2012 Bz back to 0 and the dynamic pressure went up again. Link to comment Share on other sites More sharing options...
LMolineuxLM1 Posted July 15, 2012 Share Posted July 15, 2012 Bz back to 0 and the dynamic pressure went up again. So we might be in business to see some sort of northern lights. Link to comment Share on other sites More sharing options...
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