321 FXUS01 KWBC 052016 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 415 PM EDT Fri Sep 05 2025 Valid 00Z Sat Sep 06 2025 - 00Z Mon Sep 08 2025 ...Strong storms capable of strong wind and isolated tornadoes are probable for the Northeast on Saturday and extending southwards along the Appalachians ... ...Thunderstorm chances will continue into the weekend for the Inter-Mountain West as monsoonal moisture remains in place and for the Pacific Northwest as an upper-trough moves into the region... ...Freeze Warnings and Frost Advisories are active for the Northern Plains as strong high pressure settles over the cool, post-frontal air mass... On Saturday, as the front moves eastward, strong to severe thunderstorms will develop over parts of the Northeast, Mid-Atlantic, and along the Appalachian Mountain spine. The Storm Prediction Center has a Slight Risk for severe storms (level 2/5) for areas mostly along the I-95 corridor from Pennsylvania to New England. The main weather concerns will be strong winds and isolated tornadoes with sufficient low level shear and instability. Some hail will also be possible. Farther south along the Appalachians from Virginia to Georgia, some storms could produce gusty winds with any wet micro-burst, but the severe weather threat should be less organized. General thunderstorms will also be possible for Florida and the Carolinas, the southern Plains, and most of the Mountain West over the weekend. Moreover, monsoonal moisture, partially enhanced by the remnants of Lorena near Baja California, diurnal heating, and upper-level impulses will produce showers and thunderstorms capable of producing locally heavy rain over the Mountain West on Saturday. Burn scars and sensitive terrain could see isolated flash flooding. Additionally, the Northeast is under a Marginal Risk for Excessive Rainfall on Saturday as thunderstorms with ample moisture and the potential for intense hourly rainfall rates could bring a flash flood warning or two over mountainous terrain and/or over urban areas. On Sunday, moisture will return to Texas and interact with a front to bring localized flash flooding potential. However, the overall threat has decreased from earlier forecast this week, but still stay tuned to the skies. Lastly, a tropical air mass will persist over Florida and may foster locally heavy storms capable of producing water ponding in low lying areas for this upcoming weekend. A cold, continental high pressure has settled across the northern U.S. as the cold front has now passed to the southern Plains per this afternoon's surface analysis. This anomalously chilly air mass for early September has prompted weather forecast offices to issue Freeze Warnings and Frost Advisories for portions of North Dakota for Saturday morning. A Frost Advisory is also in effect Saturday morning for northern Minnesota. Low temperatures in the areas above may reach or fall below 32 F. This weekend will see potential daily record low temperatures across the Midwest and Plains with morning temperatures in the upper 30s and low 40s. The cool morning lows, mostly in the 40s, will shift eastward for Sunday and Monday mornings for the Ohio and Tennessee Valleys and the Northeast as the cold front progresses southeastward. High temperatures for the weekend will be very fall-like with high temperatures in the 50s and 60s across the Great Lakes and upper Midwest to the low 70s from the Mid-Atlantic to the Ohio/Tennessee Valleys by Sunday. With high pressure in place, ample sunshine will be dominant on Sunday after a threat for a squall line on Saturday with the front. I also wanted to mention the poor air quality issues out West from wildfires. A lot of western weather forecast offices have issued Air Quality Alerts. Sensitive populations should try to limit exposure to outside smoke and so activities indoors. Smoke looks to remain for the Pacific Northwest through Sunday per the latest model guidance. Wilder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$