textproduct: Duluth

KEY MESSAGES

- Dangerous fire weather on Friday, with a Fire Weather Watch in effect.

- Near-critical fire weather conditions expected today in north- central Minnesota and Saturday in northwest Wisconsin.

- Severe thunderstorm chances and a heavy, beneficial rain return to the region Sunday evening into Monday.

DISCUSSION

Issued at 300 AM CDT Thu May 14 2026

High pressure currently dominates the Northland early this morning, providing clear skies and light winds for all but the Brainerd Lakes that have allowed temperatures to drop into the low-30s to mid-40s. Frost Advisories remain in effect until 7 AM for much of the Arrowhead and northwest Wisconsin; now also including central and northern St. Louis County in a recent expansion in area of that headline. Conditions will improve rapidly after sunrise as the surface high slides eastward and southerly flow begins to ramp up across the region.

For the rest of today, a tightening pressure gradient between the departing high and an approaching Canadian low will drive increasing southerly winds. Expect gusts of 25 to 35 mph, particularly across north-central Minnesota. While a warm front lifting into the area will bring increasing cloud cover and a chance for showers by late afternoon, the initial dry air mass will result in humidity values dropping into the mid-20 to 30 percent range. This combination of wind and low humidity has prompted a Special Weather Statement for near-critical fire weather concerns today. High temperatures will reach the upper 60s to mid 70s for most, though Lake Superior will keep the immediate shoreline much cooler in the 50s.

A dangerous fire weather setup arrives on Friday. A cold front will sweep through the region, followed by deep mixing within a very dry airmass. Westerly to southwesterly winds are expected to gust between 30 and 40 mph in northern Minnesota and 20 to 30 mph in northwest Wisconsin. Relative humidity values are forecast to plummet into the upper-teens and low 20s. A Fire Weather Watch remains in effect for nearly the entire Northland, as any fires that start will be difficult to control and spread rapidly. North St. Louis County was added to the Fire Weather Watch early this morning. Temperatures on Friday will be quite warm, peaking in the 70s to low 80s, further adding to the volatile fire weather conditions.

Overnight recovery of relative humidity Friday night is likely to be minimal for east-central Minnesota and all of northwest Wisconsin. The current forecast has trended drier for those recovery RHs Friday night (now 45-55%). These continued dry conditions only aid in helping to create another round of near- critical fire weather conditions Saturday. Temperatures will have dropped towards normal for northern Minnesota, but remain warm in northwest Wisconsin. These warm temperatures combined with a still-dry airmass and gusty northwesterly winds Saturday create those forecast near-critical fire weather conditions mainly in northwest Wisconsin.

The weather pattern shifts significantly by the second half of the weekend as a powerful low pressure system moves toward the Upper Midwest. Sunday will start dry, but moisture will surge northward by the afternoon. This will help to create rapidly increasing chances (10-40% in afternoon to 50-90% in evening) of rain and thunderstorms Sunday late afternoon and evening. Expect widespread rain and embedded thunderstorms. By Sunday night, the trend towards a heavy rainfall footprint (45-65% chance of 2 inches or more by Tuesday morning) heavy rainfall develops and lingers into Monday over the region. While this rain is much needed, the high rates could lead to localized ponding on roads and urban surfaces. We are also monitoring the potential for severe thunderstorms, particularly in northwest Wisconsin, depending on how far north the warm sector of the storm can reach. Cooler and unsettled conditions will likely linger for Tuesday and Wednesday with additional rain shower chances and gusty northwest winds.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 636 AM CDT Thu May 14 2026

VFR conditions prevail through 21Z today. Breezy southeast turning southerly winds will occur today, strongest in north- central Minnesota. For Lake Superior shoreline terminals, expect an easterly component off the Big Lake. An approaching warm front this afternoon brings building high-based vicinity shower chances 21-03Z west to east. Have opted for mainly VCSH with a couple of hours of PROB30 or TEMPO at this time for all terminals except BRD/HYR where a bit higher instability in the afternoon and evening could support an isolated thunderstorm. As the winds veer southwesterly behind the warm front a period of low- level wind shear is forecast 00-07Z this evening. The residence time of the low level jet this evening only looks to be about 3-4 hours at any terminal though. Expect a fairly well- mixed boundary layer tonight under the tight southerly flow regime. Terminals along the North Shore, especially in the Tip of the Arrowhead will have to be monitored though for lingering MVFR ceilings after the warm front moves through into the early Friday morning hours.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 325 AM CDT Thu May 14 2026

Easterly winds quickly increase in speed late morning to this afternoon at the head of the lake. A Small Craft Advisory begins this afternoon for the Twin Ports to Silver Bay. Winds shift to southerly tonight and southwest on Friday, with gusts up to 30 knots and waves building to 3 to 6 feet along the North Shore. There is a 50-60% chance of a few gale-force wind gusts around 35 knots between Grand Portage and Isle Royale Friday and these trends will have to be monitored if an Upgrade to the Small Craft Advisory may be needed at all. Hazardous conditions for small vessels will persist through Friday evening before winds ease Friday night. Expect lingering elevated swell into Saturday morning for any weekend small craft plans on the Big Lake.

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

FIRE WEATHER

Issued at 315 AM CDT Thu May 14 2026

Southerly winds will be gusty today ahead of a warm frontal passage late this afternoon to early overnight. These southerly winds gusting 25 to 35 mph, strongest in north-central Minnesota, combine with a lingering dry airmass to create near- critical fire weather concerns today through about mid-afternoon for the Brained Lakes northward in north-central Minnesota. A Special Weather Statement was issued for those fire zones as a result through 4 PM today. From mid to late afternoon, dewpoints will increase notable associated with the incoming warm front and help to moderate out RHs by late afternoon and evening.

Scattered high-based rain showers and an isolated thunderstorm pass overhead today or in the vicinity of most locations from late afternoon to early overnight hours. Most places see a Trace to a few hundredths of an inch of rainfall, but a few lucky spots get a tenth to maybe a quarter-inch. Expect gusty and erratic winds not only near thunderstorms late today, but also near any rain showers given the high-based nature of these showers and dry air below.

Dangerous fire weather conditions are ahead for Friday. A Fire Weather Watch is in effect for Friday across nearly the entire Northland. West winds on Friday will be sustained 10 to 20 mph and gust up to 35 mph with relative humidity values dropping as low as 17 percent.

Overnight recovery of relative humidity Friday night is likely to be minimal for east-central Minnesota and all of northwest Wisconsin. The current forecast has trended drier for those recovery RHs Friday night (45-55%). These continued dry conditions only aid in helping to create another round of near- critical fire weather conditions Saturday. Temperatures will have dropped towards normal for northern Minnesota, but remain warm in northwest Wisconsin. The warm temperatures combined with a still-dry airmass and gusty northwesterly winds Saturday create those near-critical fire weather conditions mainly in northwest Wisconsin.

Widespread heavy wetting rainfall Sunday evening into Monday with limited severe storm chances for northwest Wisconsin mainly Monday.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...Frost Advisory until 7 AM CDT this morning for MNZ011-012- 019>021. Fire Weather Watch from Friday afternoon through Friday evening for MNZ010-011-018-019-025-026-033>038. WI...Frost Advisory until 7 AM CDT this morning for WIZ002>004-008- 009. Fire Weather Watch from Friday afternoon through Friday evening for WIZ001>004-006>008. MARINE...Small Craft Advisory from 10 PM this evening to 10 PM CDT Friday for LSZ121-141-142-146>148-150. Small Craft Advisory from 10 PM this evening to 4 AM CDT Saturday for LSZ140. Frost Advisory until 7 AM CDT this morning for LSZ142. Small Craft Advisory from 1 PM this afternoon to 10 PM CDT Friday for LSZ143>145.