textproduct: Duluth

KEY MESSAGES

- Scattered showers and non-severe storms during the current overnight through Saturday morning, mainly along and south of US-2. Areas of localized heavy rainfall of 1-2" or more could occur, particularly in central Minnesota east to inland northwest Wisconsin.

- Additional periods of scattered showers and storms for Sunday into Tuesday for portions of the Northland.

- Sunday evening into night and Monday look like the next potential for strong to severe storms, though the potential is not widespread.

UPDATE

Issued at 238 AM CDT Sat Aug 29 2026

Current Overnight - Today:

Widely scattered showers have formed in a warm-advection regime over portions of the Northland during the current overnight hours, with better precipitation coverage currently ongoing in far western MN and eastern SD/southwest MN. In the subsequent hours through early morning, expect coverage of elevated showers and embedded storms to increase as better moisture associated with PWAT values approaching 1.5" advecting in from the south interacts with the nose of a low-level jet. Model sounding profiles show a fairly tall/skinny instability profile with MUCAPE values of 500-1000 J/kg. While effective shear values of 25-35 kt appear marginally conducive for semi-organized storms, further assessment of the vertical profiles indicate that the shear throughout most of the depth of the storms is rather weak. Therefore, storms should keep more of a pulse to multicell cluster appearance and not pose a threat for severe weather. The best coverage of showers and storms should be along and south of the Iron Range in northeast MN and into northwest WI as activity moves west to east across the area through this morning, then lingering into the afternoon in northwest WI. However, strength of storms should be on a downward trend throughout the morning as the low-level jet slides east and weakens.

While most areas that experience showers and storms should see around 0.25-0.5" or less, HREF LPMM and some other high-res model guidance does show some potential for training thunderstorms from the current cluster near Moorhead as it moves east along the nose of the low-level jet into central MN that could put down localized rainfall amounts of 1-2" in a few hour timespan. The higher PWATs should aid in precipitation rates with those fairly slow-moving thunderstorms, as well. A second band of 0.5-1"+ precipitation potential from the Iron Range southeast into portions of northwest WI is also possible depending on how much thunderstorm development occurs in the insentropically- forced band there. Rainfall intensities should drop off towards mid-morning with the exit of the low-level jet. Given the antecedent very dry conditions across the Northland, don't expect this heavy rain to produce much from isolated ponding and only localized flash flooding IF several storms repeatedly move over the same locations for several hours.

Sunday - Monday:

Models have come into better agreement regarding the majority of Sunday remaining largely dry in the Northland without much, if any thunderstorm activity. Mostly just some potential for a few daytime showers (10-30% chances), as we decreased PoPs again. Many locations may not see any precipitation at all through Sunday afternoon.

Then, as an upper-level low moves northeast across the Canadian Prairies from late Sunday through Monday, associated shortwave energy extending east from the upper-low in the form of a negatively tilted trough will bring a return of our next round of precipitation. An occluded front extending from a surface low associated with the upper-level low southeastward into the eastern Dakotas/western Minnesota where it will be connected to another low pressure system there will then move east into the Northland Sunday night into Monday. Storms arriving from the west given the current forecast timing appear to become elevated in nature, which when combined with stronger deep-layer shear and MUCAPE values of 500-1000 J/kg and moderately steep mid-level lapse rates could pose a threat for small to large hail and a secondary threat of gusty winds. While this storm activity Sunday evening/overnight into early Monday would currently be favored in central/north-central MN northeast into northeast MN, there still remains a fair bit of disagreement amongst deterministic global and high-resolution model guidance on exact placement of the best thunderstorm chances.

Then, depending on the placement of the occluded front on Monday, there may be a window of time along and ahead of the front where strong to severe storms would be possible again in the afternoon and evening. Best indications as of now would favor the most instability for strong to severe storm development in northwest WI, though portions of the Arrowhead could see strong storms as well if the current forecast speed of the occluded front holds.

In addition to thunderstorm potential, humid dewpoints in the 60s to around 70F are forecast for Sunday and Monday. High temperatures in the mid-70s to mid-80s are forecast away from Lake Superior on Sunday due to some strong onshore flow, which could also create a threat for rip currents along the beaches near the Twin Ports. Monday will be even warmer, with highs in the upper-70s to upper-80s away from the immediate North Shore, hottest in the St. Croix River Valley and northwest WI.

Tuesday into Mid Next Week:

No significant changes to note from the previous forecast. The shower and thunderstorm potential in NW WI Tuesday PM into Tuesday night will depend on how far south the frontal boundary pushes on Tuesday before it stalls out.

DISCUSSION

Issued at 158 PM CDT Fri Aug 28 2026

Current Conditions:

Another quiet day across the region with surface high pressure slowly departing through the day. Satellite already shows increasing cloud cover spilling over from the west as the upper level ridge begins to flatten. The late arrival of the clouds plus the return of southerly winds will see temperatures a couple degrees higher today than yesterday with highs in the 70s and a few spots climbing into the low 80s.

Weekend:

Friday night cross barrier flow over the Rockies leads to the development of a surface low pressure over the Northern Plains. This system is projected to slide across SD and into southern MN with a strong low level jet ramping up through the early morning hours. The Northland should find itself on the tip of the nose of the jet which will promote some scattered showers and storms across our southern counties. The better forcing and dynamics for more robust activity stays to our south with the REFS keeping our precipitation totals fairly minimal and generally less than 0.10" If a storm does manage to develop expect some locally higher amounts. The orientation of the low level jet will ween itself out of the area through the day Saturday with the overall strength decreasing as well. We will still maintain some low end PoPs of 20-30% to account for the isentropic lift across the area but overall expect coverage and activity to decrease as it shifts to the west through the afternoon.

Models still remain in flux for Sunday's synoptic set up with the latest showing quite the decrease in PoPs. The warm front that was originally forecasted to be draped across northern MN has drifted much farther north leaving the Northland in the gap between systems. The GFS IVT also highlights the southern Pacific moisture tracking to our south and being wrapped up with the southern low moving across the Midwest. Overall, the PoPs have been decreased down to 20- 30% and based on the latest CAMs and soundings it wouldn't be too surprising if that downward trend continues in subsequent forecast packages.

Early next week:

An upper level low matures over the Canadian Prairies late Sunday into early next week and will likely bring out next round of precipitation to the Northland. With the deepening low to the north and a secondary low moving across central MN we will see an occluded front draped over the region and pushing east through Monday. A strengthening upper level jet will increase deep layer shear. The area will also sport some MUCAPE values in excess of 500 J/kg. Pairing these two we could see some strong storms develop. Will wait for more consistent model runs before diving into more details of threats and timing.

Tuesday's forecast is highly dependent on the progression of the frontal boundary on Monday. The GFS would suggest that it stalls out over NW WI while the Euro sags it further south out of our CWA. Both models do highlight a shortwave trough that will be entering from the west that day, so depending on where the front lies there will be additional rain and storm chances along the boundary.

Wednesday looks like a brief pause in the rain chances as high pressure moves over the region. This is fairly short lived as ensembles highlight another shortwave moving across the Northern Plains for Thursday.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 628 AM CDT Sat Aug 29 2026

Ongoing widespread showers and embedded thunderstorms in central to east-central Minnesota, including BRD, will continue moving east into northwest Wisconsin this morning and then exit from west to east into this afternoon. Have kept mention of VCTS or shorter periods of TSRA going at BRD/HYR/DLH, while HIB looks to be more on the northern fringe of rainfall this morning. Conditions dip to MVFR to IFR visibilities with any showers and storms moving over a terminal, while ceilings largely remain VFR to MVFR with the rain and MVFR to VFR behind it today. Models continue to show an increasing chance for deteriorating conditions in lowering clouds and fog tonight into Sunday morning, especially at DLH/HIB/HYR where probabilities are highest.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 238 AM CDT Sat Aug 29 2026

Mainly the head of the Lake and the South Shore waters should see some rain and thunderstorms through this morning, ending in the afternoon. No severe weather expected. Sunday into early Monday morning will see northeasterly winds strengthen to upwards of 25-30 kt and lead to hazardous conditions for small craft. Small Craft Advisories have been issued. Additional thunderstorms are possible Sunday night into Monday as an occluded front moves east across the area. Some of these storms could be strong with small hail and gusty winds. Outside of thunderstorm winds, winds on Monday remain around 10 kt or less before turning southwest on Tuesday with gusts of 15-25 kt developing.

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

FIRE WEATHER

Issued at 238 AM CDT Sat Aug 29 2026

Low fire weather concerns continue through Monday. Scattered shower and storm chances return late tonight across the southern 2/3 of the forecast area. Best coverage of showers and storms will be across central Minnesota east into portions of northwest Wisconsin through this morning, ending west to east into the afternoon. Most areas that see rain should see 0.25-0.5" or less, but training thunderstorms in the aforementioned area could put down locally higher totals of 1-2"+ if storms remain over a given location for several hours.

The active weather pattern holds through the rest of the weekend and into Tuesday as multiple systems bring rain chances. The best chances look to be Sunday evening/night into Monday as a frontal boundary moves in from the west. Some of these storms could become strong to severe, with hail and strong wind gusts as the main threats. Most of the Northland should be rain-free on Tuesday and Wednesday before additional scattered precipitation chances return later in the week.

See the Fire Weather Forecast product for a more thorough breakdown of fire weather conditions.

DLH WATCHES/WARNINGS/ADVISORIES

MN...None. WI...None. MARINE...Small Craft Advisory from 1 PM to 9 PM CDT Sunday for LSZ121- 148. Small Craft Advisory from 10 AM Sunday to 7 AM CDT Monday for LSZ140>142. Small Craft Advisory from 10 AM Sunday to 4 AM CDT Monday for LSZ143>145. Small Craft Advisory from 1 PM Sunday to 1 AM CDT Monday for LSZ146-147-150.