Independence Day Weather

I was wondering today, as I often do, about how often Tucson gets rain on the 4th of July.

Us Southern Arizonan’s often joke that the ‘real’ monsoon doesn’t really begin until this date.

So as I often do, I checked through the record books to see if this sentiment is correct.

July 4th

So there you have it: since 1895 rain has fallen at TIA almost half of the time.

So what about this year?

I think there will be isolated thunderstorms across Southern Arizona tomorrow, but my mantra will be this: ‘most of us stay dry.’  I think if you are South and East of Tucson, your rain chances are the greatest. I would, however, carry an umbrella just in case.

I am looking at some long-term forecast charts that are hinting at a much more active period of weather as we head into next week.

Happy birthday USA!


From the Heat to the Rain

It’s now in the record books: for the first time ever, all 30 days in June were greater than 100 degrees in Tucson. 

So if you thought it was unusually hot, you were correct.

Chapter II: The monsoon 

Thanks to the position of high pressure, which also brought us the heat, moisture has already begun moving into the region.

Dew point’s at TIA are now near 50 degrees and forecasted to increase over the next few days.

You may recall that the dew point is the absolute measurement of how much moisture is in the lower levels of the atmosphere.

The following images are high-resolution depictions of projected rainfall across the region for the next 72 hours.


This image is our 72 hour RPM model indicating a noticeable uptick in our monsoon.

We like to look at other model runs to make sure that there is consistency among our forecasting tools.


This image is from the WRF Hi-Res Model from the UA

Bottom line: The first week of July looks to be at least the beginning of what I hope is a great monsoon.