Shallow M4.2 Earthquake struck on Tuesday Evening near Santa Rosa in The United States.

Written by Earthquakelist.org on July 29th, 2026.

A shallow M4.2 earthquake struck under land 26 miles from Santa Rosa in The United States in the evening of Tuesday July 28th, 2026. Roughly 1.7 million people may have felt this earthquake.

Earthquake Summary

The earthquake struck on land in The United States, 26 miles (42 km) northwest of Santa Rosa in California. The center of this earthquake had a very shallow depth of 4 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Jul 28, 2026 07:40PM (Los Angeles Time) - Jul 29, 2026 02:40 Universal Time.
Location:	26 mi NW of Santa Rosa, California, The United States. Coordinates 38°46'37"N 122°56'8"W.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 4.2 Detected by 43 stations. Maximum Error Range ±0.2 .
Depth:	4 mi (6 km) A very shallow depth.
Max. Intensity:	V Moderate On the Modified Mercalli Scale.
Tsunami Risk:	Tsunami very unlikely While this was a shallow earthquake, it appears to have occurred under land with a magnitude not strong enough to cause tsunami's. Always stay cautious - More info here.

Minimal impact predicted

Based on scientific estimates by the US Geographic Survey (USGS), the risk of high fatalities for this earthquake is classified at level GREEN (low). They expect an 95% likelyhood of between 0 and 1 fatalities.

The USGS classifies the economic impact of this earthquake at level GREEN (low). They expect an 90% likelyhood of between 0 and 1 million US Dollars in economic damage and impact.

Roughly 1.7 million people exposed to shaking

This earthquake may have been felt by around 1.7 million people. That is the expected population size of the area exposed to a level of shaking of II or higher on the Modified Mercalli scale according to the USGS.

Moderate shaking and very light damage may have been experienced by an estimated 600 people. At V, it is the highest MMI level this earthquake has caused. Intensity level I was experienced by the majority of people (around 11 million). In their region, not noticeable and no damage can be expected.

People	MMI Level	Shaking	Damage
11,230,000	I	Not noticable	None
1,452,000	II	Very weak	None
278,100	III	Weak	Probably none
12,740	IV	Light	Likely none
600	V	Moderate	Very light
0	VI	Strong	Light
0	VII	Very Strong	Moderate
0	VIII	Severe	Moderate to heavy
0	IX	Violent	Heavy
0	X	Extreme	Very heavy

Nearby towns and cities

This earthquake may have been felt in The United States . Located 17 miles (28 km) northwest of the epicenter of this earthquake, Windsor (California, The United States) is the nearest significant population center. Windsor experienced an earthquake intensity (MMI Scale) of roughly III. That level implies weak shaking and probably no damage.

Multiple major population centers exist within 300km of the earthquake that struck today. San Francisco is located 75 mi to the south-east and experienced an intensity of II (very weak shaking, no damage). San Jose is located 114 mi to the south-east and experienced an intensity of I (not noticeable, no damage). Santa Rosa is located 26 mi to the south-east and experienced an intensity of II (very weak shaking, no damage).

An overview of nearby towns and cities is available in the overview below. If places don't have intensity data available, it likely means the experienced impact in those places was fairly small.

Overview of nearby places

Cities and Towns around the epicenter of this earthquake.
Distance	Place	Intensity (MMI)
17 mi (28 km) SE from epicenter	Windsor California, The United States.	III Weak
21 mi (34 km) NE from epicenter	Clearlake California, The United States.	III Weak
26 mi (42 km) SE from epicenter	Santa Rosa California, The United States.	II Weak
30 mi (48 km) NW from epicenter	Ukiah California, The United States.	II Weak
33 mi (53 km) SE from epicenter	Rohnert Park California, The United States.	III Weak
41 mi (66 km) SE from epicenter	Petaluma California, The United States.	II Weak
48 mi (78 km) SE from epicenter	Napa California, The United States.	II Weak
50 mi (81 km) SE from epicenter	Novato California, The United States.	II Weak
55 mi (89 km) SE from epicenter	American Canyon California, The United States.	II Weak
59 mi (95 km) SE from epicenter	Vallejo California, The United States.	I Not felt
59 mi (95 km) SE from epicenter	Vacaville California, The United States.	II Weak
60 mi (96 km) S from epicenter	San Rafael California, The United States.	II Weak
61 mi (98 km) SE from epicenter	Fairfield California, The United States.	II Weak
61 mi (98 km) SE from epicenter	Suisun California, The United States.	II Weak
63 mi (101 km) E from epicenter	Woodland California, The United States.	I Not felt
66 mi (107 km) E from epicenter	Davis California, The United States.	I Not felt
66 mi (107 km) SE from epicenter	Richmond California, The United States.	II Weak
72 mi (116 km) SE from epicenter	Berkeley California, The United States.	I Not felt
73 mi (118 km) SE from epicenter	Chinatown California, The United States.	I Not felt
74 mi (119 km) SE from epicenter	Concord California, The United States.	II Weak
75 mi (120 km) SE from epicenter	San Francisco California, The United States.	II Weak
75 mi (121 km) E from epicenter	Yuba City California, The United States.	I Not felt
76 mi (122 km) S from epicenter	Mission District California, The United States.	II Weak
76 mi (123 km) SE from epicenter	Walnut Creek California, The United States.	II Weak
76 mi (123 km) SE from epicenter	Oakland California, The United States.	II Weak
77 mi (124 km) E from epicenter	West Sacramento California, The United States.	I Not felt
77 mi (124 km) SE from epicenter	Pittsburg California, The United States.	I Not felt
78 mi (126 km) SE from epicenter	Alameda California, The United States.	II Weak
78 mi (126 km) S from epicenter	Daly City California, The United States.	I Not felt
79 mi (127 km) E from epicenter	Sacramento California, The United States.	I Not felt
81 mi (131 km) SE from epicenter	Antioch California, The United States.	I Not felt
83 mi (133 km) S from epicenter	South San Francisco California, The United States.	I Not felt
84 mi (135 km) SE from epicenter	San Leandro California, The United States.	I Not felt
85 mi (137 km) E from epicenter	Arden-Arcade California, The United States.	I Not felt
86 mi (139 km) SE from epicenter	San Ramon California, The United States.	I Not felt
88 mi (142 km) NE from epicenter	Chico California, The United States.	I Not felt
88 mi (142 km) E from epicenter	Elk Grove California, The United States.	I Not felt
89 mi (143 km) E from epicenter	Roseville California, The United States.	I Not felt
89 mi (143 km) E from epicenter	Rancho Cordova California, The United States.	I Not felt
89 mi (144 km) E from epicenter	Citrus Heights California, The United States.	I Not felt
89 mi (144 km) SE from epicenter	Hayward California, The United States.	I Not felt
90 mi (145 km) S from epicenter	San Mateo California, The United States.	I Not felt
95 mi (153 km) E from epicenter	Folsom California, The United States.	I Not felt
96 mi (155 km) SE from epicenter	Pleasanton California, The United States.	I Not felt
97 mi (156 km) SE from epicenter	Redwood City California, The United States.	I Not felt
99 mi (159 km) SE from epicenter	Livermore California, The United States.	I Not felt
99 mi (160 km) SE from epicenter	Fremont California, The United States.	I Not felt
106 mi (170 km) SE from epicenter	Stockton California, The United States.	I Not felt
109 mi (175 km) SE from epicenter	Sunnyvale California, The United States.	I Not felt
112 mi (180 km) SE from epicenter	Santa Clara California, The United States.	I Not felt
114 mi (184 km) SE from epicenter	San Jose California, The United States.	I Not felt
175 mi (282 km) E from epicenter	Reno Nevada, The United States.

Earthquake Intensity Map

The graph below overlays a map of the region around the epicenter with earthquake intensity data provided by the US Geographic Survey. The highest intensity level detected for this earthquake is V.

I Not felt

II Weak

III Weak

IV Light

V Moderate

VI Strong

VII Very Strong

VIII Severe

IX Violent

X Extreme

Earthquake Intensity Map based on Shakemap Data provided by USGS.

Aftershocks detected

After this earthquake struck, 1 smaller aftershock occurred. Just 38 sec after this main shock, an earthquake measuring MAG-2.5 was detected 0.9 mi (1.5 km) north-east of this earthquake.

In the days before this main shock, 3 smaller foreshocks were detected. Nearby this earthquake a foreshock struck 1 day earlier. It measured a magnitude of 2.8

Overview of foreshocks and aftershocks

Detected MAG2.5+ earthquakes within within 100km (62 mi), that occurred in the three days before and after the main shock.
Classification	Magnitude	When	Where
Foreshock	M 2.5	2 days earlier Jul 26, 2026 11:29PM (Los Angeles Time)	8 mi (14 km) E from Main Shock.
Foreshock	M 2.8	1 day earlier Jul 27, 2026 08:29AM (Los Angeles Time)	11 mi (18 km) E from Main Shock.
Foreshock	M 2.7	1 day earlier Jul 27, 2026 08:29AM (Los Angeles Time)	11 mi (18 km) E from Main Shock.
Main Shock This Earthquake	M 4.2	Jul 28, 2026 07:40PM (Los Angeles Time)	-
Aftershock	M 2.5	38 sec later Jul 28, 2026 07:40PM (Los Angeles Time)	0.9 mi (1.5 km) NE from Main Shock.

More earthquakes coming?

Aftershocks are usually at least 1 order of magnitude less strong than main shocks. The more time passes, the smaller the chance and likely strength of any potential aftershocks.

In only six percent of cases, significant earthquakes are followed by a larger main shock, making the current earthquake a foreshock. While the chance of this happening is not so large, it is adviced to maintain cautiousness in the hours and days following a major earthquake.

Read: How to Stay Safe during an Earthquake (cdc.gov).

Earthquakes like this happen often in the region

Earthquakes of this strength are very common in the region. This is the strongest earthquake to hit since July 11th, 2026, when a 4.4 magnitude earthquake hit 78 mi (126 km) further north. An even stronger magnitude 7 earthquake struck on December 5th, 2024.

In total, 109 earthquakes with a magnitude of 4.2 or higher have been registered within 300km (186 mi) of this epicenter in the past 10 years. This comes down to an average of once every month.

Tsunami very unlikely

DISCLAIMER: We strongly suggest to closely monitor advice from local authorities with regards to tsunami risks. Our analysis is based on automatically collected data from external sources, and these might contain mistakes. In addition, earthquakes can cause landslides that may lead to a tsunami, or be a followed by another, potentially stonger, earthquake.

While MAG-6.5+ earthquakes may cause tsunami's, it appears that the epicenter of this earthquake hit under land. In addition, the reported depth is deeper than 100km, making the risk of a tsunami even less likely. However always stay cautious and monitor advice from local authorities.

Tsunami Risk Factors

Factor	Under Sea?	MAG-6.5 or stronger?	Shallow depth?
Explanation	Almost all tsunami's are caused by earthquakes with their epicenter under sea or very near the sea. However stay cautious in coastal areas as earthquakes on land may cause landslides into sea, potentially still causing a local tsunami.	Under MAG 6.5: Very unlikely to cause a tsunami. MAG 6.5 to 7.5: Destructive tsunami's do occur, but are uncommon. Likely to observe small sea level changes. MAG 7.6+: Earthquakes with these magnitudes might produce destructive tsunami's.	Most destructive tsunami's are caused by shallow earthquakes with a depth between 0 and 100km under the surface of the earth. Deeper tsunami's are unlikely to displace to ocean floor.
This Earthquake	Not this earthquake. This earthquake appears to have struck on land far from any coast.	Not this earthquake. This earthquake had a magnitude of 4.2. Earthquakes of this strength are unlikely to trigger a tsunami.	This earthquake occurred at a depth of of 4 mi (6 km). Earthquakes this shallow could trigger a tsunami.

Sources

Last updated 29/07/26 23:58 (). This article is automatically generated based on available data. We keep checking multiple sources for additional information. This article gets updated as new details on this earthquake become available.