Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 225 PM EDT Sat Jun 16 2018 Valid 00Z Sun Jun 17 2018 - 00Z Tue Jun 19 2018 ...Strong to severe thunderstorms along with heavy rain and areas of flash flooding can be expected from parts of the Central and Northern Plains to the Upper Midwest and Upper Great Lakes... ...Very wet conditions expected for portions of the Gulf Coast, Southwest, Great Basin and Northern Rockies... ...Dangerous heat and humidity will be in place through the weekend over much of the Midwest and spreading to the East Coast by early next week... Several rounds of heavy showers and strong thunderstorms are expected to impact much of the northern tier states over the next couple of days, including a fairly large area of the Central and Northern Plains and east over to the Upper Midwest and Upper Great Lakes region as multiple waves of low pressure lift up along a frontal zone draped across the region. Some of the thunderstorms may severe during especially the afternoon and evening hours, and there will also be concerns for flash flooding given the multi-day threat of heavy rainfall and slow movement of the front down to the southeast across the Midwest. In fact, locally several inches of additional rain will be expected and especially areas of Minnesota, Wisconsin and the Upper Peninsula of Michigan and this is where the Weather Prediction Center has locally indicated a Moderate Risk of excessive rainfall going through early Sunday. The Storm Prediction Center meanwhile has portions this area also highlighted in an Enhanced Risk for severe weather going through tonight. Meanwhile, areas south and east of this front are expected to see very hot and muggy conditions, including many areas of the Southern and Central Plains, and the Midwest. Afternoon highs will generally range from the 90s to low 100s, and with the high humidity, this will promote dangerously high heat indices of that may reach as high as 105 to 110 degrees. Some major Midwest cities to be impacted by this include Minneapolis, MN; Chicago, IL; and St. Louis, MO. Some of this high heat and humidity will be arriving along the Eastern Seaboard by Monday including New England and the Mid-Atlantic where high temperatures will be well into the 90s. There will be unsettled weather developing also for the Gulf Coast states and especially areas of southeast Texas and Louisiana by Sunday and Monday as a surge of tropical moisture in off the Gulf of Mexico and the arrival of a trough of low pressure help to bring numerous showers and thunderstorms to the region. This will be beneficial rainfall overall as the region has been dry and is locally in a drought. However, several inches of rain are expected, and this area will need to be very closely monitored for flash flooding should heavier rainfall amounts materialize. The remnants of former tropical cyclone Bud meanwhile continue to lift north up across the Southwest and with this will be a significant influx of tropical moisture. Areas of heavy rainfall are expected through tonight and Sunday across areas of southern and eastern Arizona, southeast Utah, Colorado and New Mexico. This moisture arrival is well ahead of the typical onset of the monsoon season, be it should be largely beneficial as it will help to alleviate some of the ongoing drought and wildfire concerns. Nevertheless, the rain may be heavy enough to cause concerns for flash flooding as well. The Weather Prediction Center has highlighted a Slight Risk of excessive rainfall for portions of this region. Elsewhere across the West, a deep trough of low pressure will be evolving over the next couple of days which will allow temperatures across the Great Basin and northern High Plains to cool substantially and be much below normal. In fact, high temperatures will be as much as 10 to 20 degrees below normal. There will also be plenty of clouds and locally heavy rainfall across the northern Great Basin and Northern Rockies which may also result in some localized flooding concerns. Orrison Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php