At a Glance

Raymond and T.D. 21-E are brewing west and south of Mexico. Hurricane season ends on November 30. Pairs of tropical cyclones are uncommon in mid-late November.

A late pair of simultaneous tropical cyclones have formed off the coast of Mexico as we enter the last two weeks of hurricane season.

While having one or even two tropical cyclones active in November isn't unheard of, it is rare to have two churning at the same this late in the year. In fact, it hasn't happened in the satellite era before this weekend.

Neither system is expected to be a big problem for Mexico, but Raymond is expected to spread moisture well inland.

Raymond will dissipate on Sunday as it nears Baja California, but its moisture will be strewn northward and into the southwestern United States.

This burst of moisture will function as an accelerant to a pattern change already taking shape along the West Coast.

This plume will help bring the of the rainy season for Southern California and some drought-denting rains to the rest of the Southwest.

Several tropical storms and hurricanes provide moisture for Mexico and the southwestern U.S., but that usually occurs during the monsoon. This burst of moisture will be later than usual coming from the tropics, but an uptick in rain chances across the Southwest this time of year is right on time as the rainy season begins.

The last tropical storm typically forms in the eastern Pacific around November 5, .