Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 223 AM EDT Thu Jun 20 2013 Valid 12Z Thu Jun 20 2013 - 12Z Sat Jun 22 2013 ...Deep cyclone will bring unseasonably wet conditions from the Great Basin to the Northern Plains and Great Lakes along with the possibility of severe weather... ...Showers and thunderstorms will continue across the Southeast and southern Atlantic states near a dying frontal zone... A deep cyclone across the Pacific Northwest will continue to bring unsettled conditions across the northern Great Basin for the next couple days as it slowly progresses eastward towards the Northern Plains. The combination of cold air combined with available moisture and daytime heating will trigger showers and thunderstorms along the mountains which then spread eastward into lower elevations of Montana and the Dakotas into the Great Lakes. In the higher terrain, it should be cold enough for the precipitation to fall as snow in Montana and Idaho. The heaviest rainfall, along with the threat of severe weather, will spread through the northern Plains towards the Great Lakes over the next couple days per the latest thinking from the Storm Prediction Center where vertical wind shear is sufficient to organize thunderstorms. The Gulf Coast region along with southeastern Atlantic states will see a dying polar front linger over the next couple days. Southerly winds will bestow this region with copious amounts of Gulf moisture, aiding and abetting scattered thunderstorms and showers. A surface low will remain adjacent to the Carolina coast and allow some of the heavier rainfall concentrate near and to their east. Roth/Fanning Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php