Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of  the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models.  Currently the following tropical storms appear to have potential to affect seismicity in the coming week:


No tropical cyclones are currently active.


A tropical cyclone may be forming north of Madagascar. This system is currently located at 10S 50E with winds up to 30 kts and moving SSW. The antipode at 10N 130W is not a seismic area.


Another tropical cyclone may be forming northeast of the Madagascar disturbance. This is located at 5S 80E with winds up to 30 kts and moving ESE at 6 kts. The antipode at 5N 100W is near the northern East Pacific Rise and south of Guerrero, Mexico where some seismicity may be enhanced while this storm is active.







April 22, 2018 is the sixth day after the beginning of the lunar month.

Regions most likely to experience tidal triggering on this day (With associated magnitude ranges; the percent change in seismicity rate over background seismicity rate on this day of the lunar month;  statistical z-value and significance level) are:


Region          Magnitude range %change  z-value Significance level



Indian Ocean              MB>=4.0    17  2.1  0.05

Kamchatka                 MB>=4.0    35  2.6  0.03



Regions expected to experience reverse triggering (i.e. they are unlikely to experience a significant event at this period of the lunar cycle) are:



Region          Magnitude range %change  z-value Significance level


Global                    MB>=6.0   -17 -2.8  0.02

West Pacific              MB>=4.0   -20 -1.9  0.05

Yellowstone               MB>=0.0   -19 -2.0  0.05

Puerto Rico               MB>=4.0   -17 -1.9  0.05