Kevin J. Strongman, Aaron Hardin1, and Daniel Leins1
The Southwest Monsoon brings many forecast challenges for the Tucson Weather Forecast Office (WFO) between the June to September months. One of the forecast challenges the WFO faces during the season is how active the monsoon will be on that particular day and what impact storms will have on the area such as flooding. Upper air sounding data provides a snapshot of the structure of the atmosphere, and is a very useful tool to forecasters in determining how active storms will be and what their impacts to life and property will be.
This study looks to investigate how upper air sounding parameters vary based on the number of flooding reports during the monsoon using upper air data from KTUS between 1990-2017. Some of the parameters considered include precipitable water (PWAT), surface-700mb mixing ratio, convective available potential energy (CAPE), and wind direction. The goal is to evaluate each parameter and determine which parameters could be an indicator of increased chances of heavy rainfall and flooding. This knowledge could greatly increase the forecaster’s confidence when issuing Advisories, Watches, and Warnings during the monsoon season.
1National Weather Service, Tucson, AZ