Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 223 AM EDT Sat Oct 12 2024 Valid 12Z Sat Oct 12 2024 - 12Z Mon Oct 14 2024 ...Record-breaking heat forecast this weekend from parts of the Southwest eastward into the central and south-central United States... ...Developing storm system to bring unsettled weather to the Ohio Valley, Great Lakes, and Northeast through early next week... ...Locally heavy rain possible over southeast Florida... An expansive ridge of high pressure stretching from the Southwest to the central and southern Plains will result in continued record-breaking heat across portions of the Desert Southwest this weekend. High temperatures are forecast to reach into the upper 90s and triple digits, which is well above normal for this time of year. Meanwhile, anomalous late-season heat will also span into the central and south-central U.S. today with highs ranging from the upper 80s to upper 90s. Numerous daily record high temperatures are possible. By Sunday, a cold front will squash the most searing heat southward, bringing some quick relief to the central Plains. South of the front, yet another day of record heat is likely from Arizona eastward through central Texas into the Lower Mississippi Valley where highs will once again soar well into the 90s. Elsewhere, unseasonable warmth presses eastward into the Ohio Valley, Mid-Atlantic, and Southeast this weekend, with the only cooler than normal spots largely confined to the northern Plains, Great Lakes, and Northeast. However, below average temperatures will expand on Monday into much of the Midwest and East as a strong cold front ushers in the next crisp autumn airmass. The aforementioned cold front is forecast to march eastward across the Northeast today before stalling over the Ohio Valley and Mid-Atlantic on Sunday. An area of low pressure is then expected to develop along the front, strengthening as it moves eastward into Pennsylvania by Sunday night. This storm system will bring scattered to widespread showers and thunderstorms to the larger region on Sunday, which may dampen outdoor activities at times. A few isolated strong to severe thunderstorms are possible too, especially ahead of the advancing cold front from eastern Kentucky to West Virginia. In fact, the Storm Prediction Center has issued a Marginal Risk (level 1 of 5) to highlight this risk on Sunday. As the low pressure system moves along the New England coastline on Monday, cold air aloft will allow for light high elevation snow throughout parts of northern New England. Following in the wake of Hurricane Milton, strong northeasterly flow aided by high pressure over the southern Appalachians and northeast of the Bahamas will keep the threat of coastal hazards and locally heavy rain in the forecast along the Atlantic Coast of Florida. In particular, showers and thunderstorms along the southeast Florida coastline may remain somewhat stationary due to weak flow aloft, while also containing intense rainfall rates. As a result, a Marginal Risk (level 1/4) of Excessive Rainfall remains in place for this area today and Sunday in order to bring continued awareness to the threat of localized flash flooding. Snell Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php