PHOENIX (3TV/CBS 5) -- To say this year’s monsoon season has been a disappointment would be an understatement, at least if you live in the Valley.
While some parts of Arizona have seen decent storms, the storms have been few and far between for most of the Phoenix area. And as we head into the second half of August and the month September, there aren’t a lot of strong signs that the pattern will change.
Here’s a look at where we are so far:
This is the eighth driest monsoon season on record for this point in the season. We’ve seen just over quarter of an inch of rain so far at Sky Harbor where the “official” measurement for the Valley is taken. That’s 1.28 inches below average for this point in the season.
If we got no more rain the entire season (which ends Sept. 30), it would end up as the driest monsoon season on record. The current driest year on record is 1924 when the Valley picked up .35 inches of rain.
And here’s a look at the past ten years of monsoon season rain totals in Phoenix:
It’s worth noting that in 2014, we went into the last month of the season with a measly total as well, (1.23”) but that turned around quickly in September.
You might remember freeways under water, closed schools and many Valley homes flooded when Phoenix had it’s wettest day on record with 3.30 inches of rainfall in just 7 hours. One storm literally caught us up for the whole season and 2014 monsoon total ended up at 6.24”.
That stormy day was thanks to a boost of moisture from a dying tropical system to our south.
Pacific hurricanes are what we might need to get a boost this September too.
It’s been an active season so far in the Pacific basin, but none of those storms have pushed close enough to Arizona to bring us any moisture. That could change this upcoming week.
As of this writing (8/19/19), several models are showing a tropical system (potentially named “Ivo”) that could move toward Arizona late next week. That’s why the Climate Prediction Center has upgraded our current two-week outlook to include above average rain chances for parts of the state.
That being said, the one month outlook from the CPC hasn’t given us much direction for what comes after that. Their current outlook for September shows equal chances for above or below average rainfall for Arizona.
Previously, we had believed that this summer’s El Nino conditions could give us a late-season boost in precipitation, but this past week NOAA announced the end of El Nino. Sea surface temperatures are now considered to be in a neutral phase. While that may mean a more active second half of hurricane season in the Atlantic, it doesn’t say much for what may happen in the Pacific.
This makes reason number 10,000 why this year’s monsoon season has been especially tough to forecast. I was chatting with our friends at the National Weather Service this week and they say the same.
Meteorologist Bianca Hernandez with NWS had this to say. “I would say forecasting in general is very tough, so if there isn't a clear signal (for example, winter El Nino/La Nina), it makes it even harder. In terms of the monsoon, it is probably one of the most difficult forecasts. One little thing can make it or break it, and if a certain feature isn't extremely evident to us and models aren't picking up on it, it makes it an even harder forecast. The other difficult factor with monsoon forecasting is the fact that monsoon storms are very isolated in nature, meaning not everyone is going to see storms. So it might be a great forecast to people who did end up seeing rain, but it may be a complete bust to other people who may not have seen any rain.”
So we’ll have to wait and see what September brings us with the last month of monsoon season. There’s at least hope for that tropical system this next week to give us a boost. Keep your fingers crossed - the desert needs the rain and I think it’s safe to say we all are ready for a cool-down.