WEATHER PHENOMENA

 

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:

 

 

TROPICAL CYCLONE KENNETH (24S)

 

----  -------  ----------  --------  -----  ------  -------  ---------------

TC    KENNETH  2019-04-24  00:00 UT  11.1S   44.4E   90 kts  Comoros Islands             

 

TC Kenneth (24S) formed today east of the Comoros Islands with winds up to 90 kts. It is expected to track to the west over Mayotte in the next day. Some seismicity may be enhanced in the region of Mayotte. The antipode at 11N 145W is south of  Hawaii, and some seismicity may be promoted in Hawaii as this storm moves west.

 

TROPICAL CYCLONE LORNA (25S)

 

----  -------  ----------  --------  -----  ------  -------  ---------------

TC    LORNA    2019-04-24  00:00 UT  10.7S   84.4E   50 kts  South Indian Ocean             

 

TC Lorna (25S) formed today south of India with winds up to 50 kts. It is expected to track to the south over the next week. The area has little seismicity but recent activity in India may have been promoted by stresses from this storm. Some seismicity near the antipode at 11N 95W in Central America and Mexico may also be promoted by antipodal effects from TC Lorna.

TIDAL EFFECTS ON SEISMICITY

 

The full moon arrived at 11:12 UT on April 19, 2019. Longitudes which were sub-solar at this time were near 15 East and 165 West. These include areas of central and western Europe in the east and the Aleutian Islands and western Alaska in the West. Other areas which may see enhanced tidal promotion at this time are the Kermadec-Tonga arc north to Samoa. While these regions will experience maximum stress from the tidal alignment, many other areas could see enhanced seismicity in the next five days and a strong earthquake is likely in this time period.

 

 

April 24, 2019 is the eighteenth day after the beginning of the new 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

 

Pacific-Antarctic Ridge MB>=4.0 58 2.0 0.05

East Africa MB>=4.0 23 3.1 0.01

New Zealand MB>=4.0 19 2.2 0.05

Yellowstone MB>=2.0 19 2.0 0.05

 

 

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

 

Utah MB>=2.0 -19 -2.0 0.05