Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 418 AM EDT Sun Jun 04 2017 Valid 12Z Sun Jun 04 2017 - 12Z Tue Jun 06 2017 ...A complex low pressure system will bring unsettled weather into the mid-Atlantic and the Northeast early this week... ...Showers and thunderstorms will continue across the Deep South as tropical moisture moves up from the Gulf of Mexico... A complex evolution of the synoptic pattern is taking shape over the northeastern U.S. as an old occluded system near the Great Lakes is going to be reinvigorated by an anomalous upper-level low surging southward from James Bay, Canada. First of all, showers and thunderstorms ahead of the occluded system will move across the lower Great Lakes and into the Ohio Valley today before reaching southern New England tonight. Some of the thunderstorms could become severe later today over the lower Great Lakes. Meanwhile, moisture coming up from the Deep South will begin to interact with the system. This will increase the likelihood of showers and thunderstorms across the mid-Atlantic and into much of New England on Monday. A low pressure center is forecast to deepen off New England coast by Tuesday morning, bringing the rain to an end over the central mid-Atlantic. However, a lingering low pressure center will keep showers and thunderstorms over New York State eastward into New England Tuesday morning. Meanwhile, scattered showers and thunderstorms associated with an upper-level low continue to fall over a large area across the Southern/Central Plains and along the Gulf Coast. The upper low is forecast to slowly sink southward into the western Gulf Coast by Monday. The upper low will then begin to interact with moisture coming up from a tropical system in the Gulf of Mexico. As the upper low moves southward, showers and thunderstorms over Oklahoma and central Texas should taper off on Monday. However, much of the Gulf Coast eastward into Florida will see an increasing chance of showers and thunderstorms as a broad area of low pressure forms slowly along the coast during the next few days. Elsewhere, a developing front across the Intermountain West into the Great Basin will move eastward into the northern High Plains on Monday. This will bring showers and thunderstorms across the Intermountain region today, which will spread into the northern Rockies early on Monday. By Monday afternoon, more showers and thunderstorms will extend southward into the central High Plains and the central Rockies. Some scattered thunderstorms should develop in the southern Rockies and southern High Plains as well on Monday into early Tuesday. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php