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:

TYPHOON  KOINU           

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TYPH  KOINU    2023-10-01  00:00 UT  19.2N  127.3E  125 kts  East if Philippines    

Typhoon Koinu formed today in the area of the Pacific east of the central Philippines with winds up to 35 kts. It is expected to track to the west over the next several days and my enhance seismicity in the Philippines, Taiwan and the Ryukyu Islands of Japan as it passes through the region.

TROPICAL STORM RINA                 

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TS    RINA     2023-10-01  00:00 UT  27.1N   55.4W   30 kts  Central Atlantic       

Tropical Storm Rina formed today in the area of the central Atlantic east of Florida with winds up to 30 kts. It is not expected to significantly impact seismicity at this time and is expected to track to the  north  and west today and dissipate in the North Atlantic in early October.

TROPICAL STORM PHILIPPE             

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TS    PHILIPPE 2023-10-01  00:00 UT  16.6N   59.1W   50 kts  Central Atlantic       

Tropical Storm Philippe continued today in the area of the central Atlantic east of the northern Caribbean with winds up to 50 kts. It is not expected to significantly impact seismicity at this time and is expected to turn north today and dissipate in the North Atlantic in early October.

A tropical cyclone may be forming south of Oaxaca, Mexico. This system is expected to stay far south of Mexico and not to enhance regional seismicity at this time. It is currently located near 10N 100W and moving to the west with winds up to 23 kts.

TIDAL EFFECTS ON SEISMICITY

The full moon arrived on September 29 at 09:57 UT. This is the last supermoon of the year. Supermoons occur when the moon is closest to the earth on it's elliptical orbit. The considerably increases tidal stress and possibility of strong earthquakes. Longitudes which are at local solar noon at this time are localed near 30 East longitude while those at local solar midnight are near 150 West longitude. In the east these include These include Hawaii and areas of eastern Alaska and western Canada and to a lesser extent areas off the coast of Oregon and California while in the east they include Eastern Turkey where an M 7.7 hit on February 6, 2023 as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered likely in the next week at this time.

October 1, 2023  is the sixteenth 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

Kermadec MB>=4.0 14 2.0 0.05

Nevada MB>=2.0 22 3.3 0.01

Spain MB>=4.0 35 2.5 0.03

Puerto Rico MB>=4.0 18 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

So.California MB>=0.0 -8 -2.1 0.05