Active Weather
Eastern South Dakota sits at the western edge of today's Upper Midwest severe weather risk. The Storm Prediction Center draws a slight risk area running from the South Dakota and Minnesota border into central Minnesota, with hail up to about 2 inches across and wind gusts above 75 miles per hour possible where storms organize.
Forecasters expect supercells first, potentially becoming a bow echo later, which is the structure that produces a continuous line of wind damage rather than scattered spots. Probabilities are 15 percent for damaging wind, 15 percent for large hail, and 2 percent for a tornado within 25 miles of a point.
Colorado, Montana, North Dakota, Utah, and Wyoming have no severe weather or excessive rainfall risk drawn over them today.
For eastern South Dakota the practical actions are the ordinary ones: park under cover if you have it, secure anything outside that a strong gust would move, and make sure you have a way to receive a warning that does not depend on the power staying on.
Infrastructure
The Sand Creek fire in Montana stands at 34,733 acres and 15 percent containment in the National Interagency Fire Center's September 1 situation report, up two points of containment from the previous report. The Northern Rockies geographic area is at preparedness level 3.
Nationally the picture is at its highest step. The preparedness level is 5, with 84 large uncontained fires across the country. Year to date the count stands at 52,626 fires, 126 percent of the ten year average, and 8,265,751 acres, 163 percent of average.
If you are near an active fire in Montana, the number that matters is your evacuation status rather than the containment percentage. Containment describes the line around the fire, not the risk to any particular address.
No grid emergencies or water system disruptions are reported across the six states.
Public Health
No air quality advisories were confirmed for the six states this run. Smoke from fires in the Northern Rockies and the Northwest can drift well beyond the fire perimeter, and conditions change through the day. AirNow's fire and smoke map and your state or county health department are the current sources for your specific location.
No public health advisories specific to the Mountain region were confirmed this run. The Centers for Disease Control and Prevention's Health Alert Network archive could not be read without JavaScript, so this brief makes no claim about national health advisories in either direction.
Watch Item
Fire season and winter storm season overlap in this region in a way they do not elsewhere. Early September can carry an active fire in Montana and the first mountain snow in Colorado within the same two weeks. Households at elevation get the shortest runway of anyone in the country for switching from one set of preparations to the other.
The practical version of that is to do both this month. Keep the evacuation plan and the packed bag current while the fires are still burning, and at the same time service the furnace, arrange fuel, and confirm carbon monoxide alarms are working before the first cold night. The Consumer Product Safety Commission's guidance is alarms on every level of the home and outside sleeping areas, tested monthly.
Drought remains the underlying condition. The United States Drought Monitor released September 2, using data through August 25, put 56.61 percent of the lower 48 states in drought, with 43 states carrying at least moderate drought somewhere inside them. In this region drought shapes both how long fire season runs and what next spring's water supply looks like.
Explore Today
Fire exposure and evacuation routes for your specific address.
Water, light, food, and a plan, packed for a household that may need to leave.
At elevation, heating season starts earlier than the calendar suggests.