It was nice to be QRV for a portion of last night’s session as stormy weather abated temporarily. It seems tonight I might be receive-only or fully QRT depending on the location of the approaching warm front. Many in the southeastern US have commented on the noise levels for the approaching storm system which will be impacting their local areas with strong storms by the Saturday. By then we should begin drying out before the next storm system arrives next week.
As I complain about being QRT for a few days, Laurence, KL7L / WE2XPQ, posted a few pictures of his aurora on the ON4KST chat/logger. Aurora is a deal-breaker when it comes to MF propagation, particularly when a station is under its umbrella. I supposed I should count my blessings that I am far away from the auroral zone and the attenuation it brings to low band propagation.
As I am preparing this report, another shock wave has reached Earth resulting in elevated K-indices. Solar wind is elevated above 400 km/s and the Bz is pointing to the North.
John, WA3ETD / WG2XKA, reports, “A slightly improved session last night, although unique exchanges (24) remain low compared to the past two weeks. The PNW reappeared as propagation creeps back.” Let’s see how long the band holds with the most recent shock wave!
In spite of operating last night, I failed to take an MF WSPR census during the evening in North America. The distributions of stations on the WSPR map looked relatively normal, however.
Regional and continental WSPR breakdown’s follow:
There were no trans-Atlantic or trans-African reports during this session. EA8/DJ9XK, EA8/LA3JJ, UA0SNV, and ZS1JEN were present during this session but no reports were found in the WSPRnet database.
Eden, ZF1EJ,continues to do well, reporting stations in the eastern and southern US in spite of the storm system located to his North.
Laurence, KL7L / WE2XPQ, was successful at taking advantage of the salt water path to Hawaii and the west coast of North America. KL7L was designated as as receive-only during this session and also experienced success on the paths that were primarily over salt water.
Merv, K9FD/KH6 / WH2XCR, reports storms and 50 mile per hour winds at his QTH. Even so, the path to JA and VK was open to a degree. Merv reports that he was decoded by Roger, VK4YB, and decoded Phil, VK3ELV, but these individual paths did not exhibit reciprocity. John, VK2XGJ, notes that he was using the R75 receiver during this session but elevated local noise and QRM from wandering local signals prevented any real chance of a decoding Merv. Even with the improved geomagnetic conditions through much of this session, its my believe that the damage has been done and the electron reservoirs are full. It will take a few quiet days for all of them to precipitate, just like a tank of bad gasoline.
In Australia, Phil, VK3ELV, received reports from WH2XCR and JH3XCU. One of the JA spots was from late in the previous session.
Additional comments, statistics, anecdotes and information:
The ARRL has filed an Ex-Parte comment on the matter of ET 15-99. Details and links can be found in the ARRL news. One stand out item from this article is that there is an expectation that rules and requirements will be detailed during the first quarter of 2016. We are very close to the end of the first quarter so its conceivable that we will have more information any day. The ARRL executive committee meeting is being held this weekend here in Dallas and its possible that additional information will become available next week. Based on information that my acquaintances with the FCC have provided, we are very close to being on schedule, as I was told last year to expect action by the second quarter of 2016. Let’s see what happens!
Jim, W5EST, provides part 3 in a recent series entitled, “TESTABLE RULE OF THUMB FOR N.Am.-VK PROPAGATION?”:
“The March 4-5 blogs described a possible predictor of Pacific Northwest to Australia (PNW-VK) propagation and discussed a work plan for testing. A PNW-VK propagation predictor can combine or mix various data types to make a mixed predictor. The March 7 blog discussed some general features of three categories of propagation predictors. The February 29 blog exercised a testing method on several predictors for 630m daytime propagation and found a calendar-based predictor was best for that topic based on the available information.
Since then I’ve cherry picked my log, this blog, and the WSPR database for information starting last August specifically for the PNW-VK topic. If you prefer to call the PNW-VK predictors tested here predictors of actual decodes, instead of predictors of propagation itself, you are probably right.
Last fall, it took me a while to get the habit of logging E-VK storm data from WWLLN consistently. Likewise, the number of XGP spots at XCR exceeding -11dB was absent some days. Nevertheless, that’s just “life as we know it” for analysts who work with real data, warts and all. Fortunately, enough information was collected to make some analysis possible.
VK stations started decoding western N. America stations this season August 14. By October 15, 2015, the N.Am.-VK season was over except for three outlier days November 19 & 21-22. In 2014, my records indicate the N.Am-VK season ran Aug. 25 to Oct. 7, 2014.
Accordingly, for the 182 days of Summer-Fall 2015 (June 20–Dec. 20 solstices), 4-quadrant diagrams analyze a calendar-based predictor “Aug14Oct15” and a mixed predictor “Aug14Oct15 & NoE-VKstorms.”
*Note: Precision may be higher and numeral “30” may be lower if analyst failed to log all days with E-VK Tstorms.
If used by itself the calendar predictor would suggest– to a N. America station only interested in getting at least one VK spot–to operate absolutely every last one of the 63 nights Aug. 14 to Oct. 15.
Now let’s drill down inside the 63 days of Aug. 14-Oct. 15. 19 of those days featured N.Am.-VK decodes. What characterizes those 19 special days? Out of 25 days in the period for which I logged east-VK Tstorm absent or present, 14 of them were logged present with east-VK Tstorms. Of those 14 days, on 2 days I logged a single N.Am.-VK decode each of the 2 days.
On the other 11 wx-logged days when east-VK Tstorms were logged absent, only one of them showed N.Am.-VK decodes when at least 4 XGP-xcr decodes were at least as as strong as -11dB. Out of 20 days for which 4 XGP-xcr >=-11dB in the log, only 8 of them were associated with N.Am.-VK decodes. So XGP-xcr SNR as an indication of general prop conditions doesn’t help predict N.Am.-VK decodes.
What lessons do I take away from this? First of all, a mixed predictor based on the calendar and absence of east-VK Tstorms seems to be one the limited evidence can support at this time. A calendar-based predictor alone has a better false negatives rate and the mixed predictor has better precision. Second, adding an XGP-xcr SNR-based predictor to the mix doesn’t help, notwithstanding the predictive value that I thought last August a SNR-based predictor might offer. Reality is a tough taskmaster!
Could we do better somehow? Could we assemble space weather information that would characterize the 19 special days? Solar X-ray emission seems a doubtful guide. During Aug. 14 to Oct. 15, M-class flares happened 15 days. But only one out of 15 M-flare days had N.Am.-VK decodes. 11 of the 19 N.Am.-VK decode days had at least C-flares but that means 8 of the 19 days lacked a flare, pretty near 50-50 with these small numbers and useless for prediction.
Perhaps Bz, solar wind or Dst could be included to make a better predictor.** This blog has maintained that type of space weather information since October 28.
The XCR-vk path decodes peaked up Nov. 19-22, suggesting we pay attention to path conditions across the equator to VK. Perhaps records of such XCR-vk path decodes could help form an improved predictor.
If you or I find valuable predictive information for PNW-VK or any other path, let’s do a further blog post to cover it. GL!
Additions, corrections, clarifications, etc? Send me a message on the Contact page or directly to KB5NJD <at> gmail dot (com)!