Plots include data from yesterday and today. Check the time (UTC 24-hr) to see where the new data is being recorded. I'm contemplating other interesting data to plot, instead of the unchanging geiger counter and drifty ionization chamber.
I'm experimenting with this plot. I've switched to points instead of lines and increased the rate to sample every 50 seconds (still with 5 minute web updating). Using points instead of lines means the time and associated data can be on any row without causing "retrace" lines as the spreadsheet tries to connect the dots. There will be 1728 points on the chart, so it should look fairly continuous. I'll play with the dot size tomorrow. This modification to the spreadsheet means that I can start and stop it at any time, without completely disrupting the plot. The line in the data should disappear today.
The plot is the Sid Seizer. SIDs will cause spikes between about 12:00 and 0:00, where the plot is normally low. The high portion between 3:00 and 11:00 is nighttime sky wave.
To confirm a flare, see http://www.swpc.noaa.gov/today.html#xray . For a six hour close-up view, see http://www.swpc.noaa.gov/rt_plots/xray_1m.html.
If the signal drops to zero suddenly, WWVB may have gone off the air; Check the NIST website to confirm.