The moisture of ex-Tropical Storm Alvin is bound for the Southwest U.S., where it will help to enhance unusual rainfall for this time of year and then go on to help spawn storms in the central U.S. in the week ahead.
Forecast
Remnant moisture from Alvin in combination with an upper low will help trigger the development of showers and thunderstorms over the Southwest U.S. through Monday, including Phoenix and Tucson. The additional cloud cover and rain will keep temperatures as much as 15 degrees cooler than we have seen recently.
Moisture Associated With Alvin
This is a rather unusually wet pattern for the end of May and beginning of June, there. June is typically one of the driest months of the year in this region since it precedes monsoonal rains that arrive later in summer.
Up to an inch of rain could fall across portions of the Four Corners region. Localized flash flooding is possible on in southern Arizona through Monday morning.

Additional Moisture Helps Fuel Storms In The Plains
The severe thunderstorm chances will also grow from the Dakotas to the Central Plains Monday and Tuesday as Alvin’s moisture gets pulled into a sprawling area of low pressure that will pivot from the Central Rockies to the Upper Midwest.
NOAA’s Storm Prediction Center has said that severe weather is possible:
– Monday: Storms are most likely from the Texas Panhandle to southern Minnesota. However, we could still see storms from western Texas to northern Minnesota. The main threats with these storms will be damaging winds and hail, as the storms march eastward throughout the afternoon and evening hours. Places like North Platte, Amarillo, Sioux Falls and Denver need to be on the lookout for storms.

Severe Thunderstorm Outlook
– Tuesday: From central Texas to southern Wisconsin will see the biggest threat, however, we could see scattered storms stretch as far north as the Upper Peninsula of Michigan. Strong, damaging winds and hail will be the main threats. This includes places like Dallas, Tulsa, Kansas City, Cedar Rapids and Madison, Wisconsin.

Severe Thunderstorm Outlook
Make sure to check back often for updates to the forecast.
Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world’s biggest weather and climate stories for the last two decades.
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