DISCUSSION
Issued at 408 PM CDT Sun Sep 15 2024

This is one of those days where it is very easy to get absorbed in the fine details of what is going on in the atmosphere, even though those details are those which only a meteorologist would find neat or interesting, and have only a minor impact upon the forecast as a whole. Sadly, since this discussion is for a broader audience than hard core weather nerds and needs to be produced in a reasonable time frame, these details will be glossed over.

The cold front from yesterday has now broadened out to little more than a trough axis and moisture boundary this afternoon, and has pretty much stalled over eastern North Dakota, extending southwest into central South Dakota. East of that boundary, we have a nice cumulus field and some decent instability, but with little/no shear and nothing to trigger any cells into more vigorous growth, we have not yet seen any convection develop over the forecast area. However, there is an area of convergence along/ahead of that trough axis that may be able to produce showers and thunderstorms during the late afternoon and evening hours that should slide east overnight. Since the high resolution models seem to have a similar depiction, have gone with some slight to chance pops along and north of the Iron Range for tonight into Monday. Our warm temperatures will also continue with the southwest flow across the region. Temperatures are running 10 to 15 degrees above normal, which is more like August temperatures here in mid September.

This flow pattern continues into Tuesday and Wednesday, with southwest flow both at the surface and aloft. Precipitation chances are going to depend on getting some sort of feature to help generate them, and while we have been developing some decent instability with the heat and humidity, shear and forcing parameters are weak and I have low confidence in getting anything with much organization that could produce significant rainfall. Unfortunately we have to maintain some small pops, though there will be long periods of dry weather. Temperatures will also remain significantly above normal.

For the later half of next week, there are some increasing probabilities of getting significant rainfall, but these are dependent upon getting the blocky pattern currently over the eastern CONUS to break down, allowing the strong upper low over the western CONUS to push a decent shortwave with some better forcing in our direction. There is one around Wednesday which misses us to the northwest, but there are hints of another that may affect us in the Friday into Saturday time frame, as well as signals that the blocking pattern finally breaks down by then as well.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/
Issued at 634 PM CDT Sun Sep 15 2024

Scattered showers and perhaps a few storms (20-30% chance) could develop near a weak surface boundary across north-central Minnesota by mid evening and move into the vicinity of KINL for the late evening hours before moving southeast of KINL towards KHIB overnight into early Monday morning, with VCSH and VCTS covering this threat of scattered convection. Expecting development of some fog at KDLH, KHIB, and possibly KINL tonight, some of which could become IFR to LIFR at KDLH/KHIB between roughly 09Z-13Z Monday. Expect VFR conditions to return after 14Z Monday morning, though scattered showers and storms are expected to move out of northwest Minnesota towards KINL Monday evening just after the end of the current TAF period.

MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/
Issued at 408 PM CDT Sun Sep 15 2024

Generally quiet conditions on the lake with winds of less than 15 kts and waves of less than two feet are expected through at least Tuesday. Southeast winds should increase somewhat going into the middle part of the week with building waves, but waves should still remain under 3 feet. Of note, while most of the lake should have generally south to southeast winds, the southwest arm of the lake will have a more easterly perhaps even northeast pattern during the daytime with the land so much warmer than the lake, but veering into the southeast at night with the temperature difference is not so large.

For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt.

DLH WATCHES/WARNINGS/ADVISORIES
MN...None.
WI...None.
MARINE...None.