October 2025 Rainfall Harbinger of Things to Come?

Last month Phoenix recorded near record rainfall.  In fact, it was the third wettest October on record.  Considering that the southwest has been in a drought for the better part of the last 25 years, this kind of precipitation is significant on a number of levels.  Not only does it help replenish our lakes, reservoirs and ground water it also helps end the summer heat.  As we discussed in previous blogs, Phoenix suffers from a “heat dome” June to September.  Meaning that the intense heat put off by the city itself creates a dome of heat that makes it difficult for rain storms to penetrate.

Rain events like October’s help to cool the city down, significantly impacting our weather.  Instead of sun all day and slow dissipation of heat at night culminating in an intense heat dome, temperatures can cool more at night, thus resulting in a quicker end to the summer temps.  Those October rains accomplished this and helped get us out of the 100s sooner than we might have otherwise.

The rain events were remnants of tropical storms that were actually hurricanes at one point.  They formed south and west of Mexico and worked their way up the Mexican coast before making landfall on or near the Baja.  Landfall meant that the high winds dispersed, but the moisture kept moving north and east, eventually impacting the southwestern United States.

So how is all of this relevant to real estate?  Whether or not you believe in climate change, the data indicates some pretty significant changes are happening.  Wildfires in California, Hurricanes in Florida, Nor’ Easters in New England, tornados in Mississippi are just a few examples of natural disasters that are occurring with greater frequency and ferocity.  Just look at the insurability of some of these places.  Many insurers won’t even issue policies, or if they do, the rates are astronomical and are laced with exceptions.

In Phoenix, we don’t really have this problem.  But if we are going to see a higher incidence of major rain events like last month then we may have a reduction in the amount of time our temperatures push over 100 degrees.  This summer and fall the Pacific Ocean was particularly warm. In fact, for some months, all-time records were set.  Warm oceans equal strong tropical storms and hurricanes.  So if a warm Pacific is now the norm, then maybe late summer/early fall rain is also going to be a regular occurrence.  This may cut our summers shorter and get us into the weather that we all associate with Phoenix: Perfect!