Tracking generally northwestward, the newly designated tropical storm steadily organized in a moderate shear environment.

Thereafter, the cyclone began a period of rapid deepening, and it subsequently attained its peak intensity with winds of 125 mph (201 km/h) and a minimum pressure of 950 mbar (950 hPa; 28 inHg) early on September 6.

A track over progressively cooler waters and into a more stable environment prompted a weakening trend after peak intensity, and by early on September 8, the system no longer maintained enough convection to be considered a tropical cyclone.

On August 30, the National Hurricane Center (NHC) indicated the potential for an area of low pressure to form offshore the coastline of Mexico and slowly develop over subsequent days.

[1] This projection came to fruition the next afternoon, when a large area of showers and thunderstorms in association with a trough of low pressure was noted.

[2] Amid a generally favorable environment with moderate wind shear and warm sea surface temperatures, convection steadily coalesced atop a distinct low-level circulation, and the disturbance acquired enough organization to be deemed a tropical cyclone at 15:00 UTC on September 2; it was designated Tropical Storm Norbert in accordance with an Advanced Scatterometer (ASCAT) pass.

[3] Norbert moved generally northwestward succeeding formation, steered around the southwestern periphery of a subtropical ridge across Baja California and northern Mexico.

[4] All the while, the cloud pattern of the cyclone progressively improved, with a symmetric central dense overcast and distinct rainbands on convectional satellite, and a formative inner core with hints of a small mid-level eye on hurricane imagery.

[6] Continuing on a general northwestward trajectory, increased easterly wind shear caused the system to temporarily lose organization during the pre-dawn hours of September 4 as the low- and mid-level circulations became dislocated.

[11] After attaining its peak intensity with maximum winds of 125 mph (201 km/h) and a minimum pressure of 950 mbar (950 hPa; 28 inHg), Norbert began to track over cooler sea surface temperatures, and a weakening trend ensued.

[19] A man died in Mazatlán, Sinaloa after being swept away by a swollen stream, and two women in Chihuahua drowned while driving across a flooded creek.

[30] The circulation of Norbert, in conjunction with the remnants of Atlantic Tropical Storm Dolly, spread moisture across northwest Mexico and into the southwestern United States.

In response to the flooding, Governor Jan Brewer issued a state of emergency and ordered nonessential workers to remain at home.

Due to the severity of damage, the New Mexico Department of Transportation closed the road indefinitely and stated it could be more than a month until it was re-opened.

[41] In Nevada, rainfall totaled over 4 in (100 mm) in a short period of time, causing the worst flooding in the Moapa Valley since 1981.