It's safe to say that two months in the 2009 Monsoon season has been a huge disappointment.
At Sky Harbor Airport, the official reporting station of the Phoenix metro area, has received only .70" of rain so far.
See pictures of this year's summer storms in the attached photo slideshow.Compare that to last year at this time where the airport had already received 3.63".
The Valley, on average, has received a dismal .33" compared to this time last year when that number was 1.85".
These numbers represent the Phoenix Rainfall Index which is an average of 132 rain gauges around the Valley. This helps us get a better representation of the how the Valley is doing as a whole.
Here's how much rain has fallen around the Valley through August 15th:
Ahwatukee - 1.38"
Anthem - .75
Avondale - .79"
Buckeye - .78"
Carefree - .79"
Cave Creek - .55"
Chandler - 1.06"
Deer Valley - .67"
El Mirage - 1.06"
Fountain Hills - .47"
Gilbert - .35"
Glendale - .39"
Goodyear - .91"
Laveen - 1.42"
Luke AFB - 1.57"
Mesa - 1.26"
Peoria - .43"
Paradise Valley - .67"
Queen Creek - .83"
Scottsdale - .79"
Sky Harbor - .70"
Surprise - .51"
Tempe - 1.38"
Wickenburg - 1.26"
The main reason for a down monsoon is the placement of high pressure in the southwest and the low pressure over the Great Lakes and New England.
Normally we get high pressure over the Four Corners or the Great Basin for a week straight resulting in consecutive days of thunderstorms along the rim and a few of those making their way into the Valley or the deserts.
This season, the high pressure ridge has been floating near the Four Corners for a day or two and then retreating into New Mexico, northern Mexico, and at times all the way into central Texas.
This pattern results in drier conditions in the Southwest with hot and dry conditions in Texas and at the same time, cooler and wetter weather in the Great Lakes and the Northeast.
Another reason may be the lack of tropical systems in the Eastern Pacific this hurricane season. Many times a tropical storm or hurricane will get close to the southern tip of the Baja and tropical moisture spreads north all the way into Arizona helping to jump start our monsoon. We have seen none of that so far this season.
Looking ahead over the next week or so, the monsoon pattern doesn't appear to get going again until the end of next week. Keep your fingers crossed. We are running out of time.
If not a single drop of rain falls for the rest of the season, this monsoon would be the 5th driest on record.
