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 STORM RAMON (20E)

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TS    RAMON    2023-11-26  00:00 UT  14.9N  122.7W   50 kts  North Pacific Ocean     

TS Ramon (TD 20E) continued today in the area of the north Pacific Ocean with winds up to 50 kts.  It is expected to track to the northwest and not to influence regional seismicity at this time.

TIDAL EFFECTS ON SEISMICITY

The full moon will arrive on November 27, 2023 at 09:16 UT.  Longitudes at local solar noon were near 37 East while those at local solar midnight are near 143 West longitude. 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. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A moderate to large aftershock is possible in Turkey at this time.

November 26, 2023 is the thirteenth 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

Central America MB>=4.0 10 2.1 0.05

Global MB>=6.0 15 2.5 0.03

Utah MB>=0.0 14 2.7 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

Central California MB>=2.0 -8 -2.2 0.05