229
FXUS63 KDLH 120906
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
406 AM CDT Mon May 12 2025

.KEY MESSAGES...

- Unseasonably warm and dry conditions persist through early
  this week.

- Red Flag Warnings are in effect across the Northland today.
  Additional fire weather alerts may be needed for Tuesday.

- A pattern shift occurs later this week, with hot temperatures
  ending and precipitation chances returning.

&&

.DISCUSSION...
Issued at 406 AM CDT Mon May 12 2025

A broad upper-level ridge remains in place over the High Plains
and Great Lakes this morning while a cutoff low resides over
Louisiana. This pseudo Rex Block is forecast to slowly break
down as a significant trough moves into the Rockies Tuesday and
Wednesday. This will keep strong southerly warm air advection in
place over the Northland. Record and near-record high
temperatures are forecast again today. Southerly winds are
forecast and will be gusty, though not as strong as Sunday.
Critical fire weather conditions are forecast with minimum RH
values in the teens except along the North Shore where a lake
breeze will keep the drier conditions farther inland. A Red Flag
Warning is in effect for the entire Northland. High
temperatures today will be in the middle 80s to low 90s, except
for portions of the Arrowhead where the lake breeze will keep
temps a little cooler.

Conditions remain similar on Tuesday with very dry air in
place. Wind gusts return and will likely be a little weaker once
again. Highs may be a little warmer, particularly over
northwest Wisconsin. Highs will be in the middle 80s to low 90s
across the area, with the exception of the Arrowhead.

As the blocking pattern begins to break down on Wednesday,
temperatures will trend a bit cooler and winds will be less
gusty. The strongest warm air advection will be shunted farther
west as the upper low moves into the Ohio River Valley. Near-
critical fire conditions may persist, but widespread critical
values appear unlikely.

As the upper-level trough progresses farther east on Thursday,
precipitation chances return to the Northland. We will see a
chance of showers and thunderstorms return to the region. A few
strong to severe storms are possible Thursday afternoon and
evening. The probability of seeing more than one-quarter inch of
rain is more than 80% across the Northland Thursday and Friday.
The probability of a half inch or more is greater than 50%.

A new cutoff low is forecast to develop in the trough Thursday
night and Friday and will slowly migrate northeastward into the
Canadian Maritimes by Sunday afternoon. A ribbon of colder air
aloft will wrap into the system from the west which may result
in some "conversational" snow late Thursday night and Friday.
Accumulations should be limited to grassy areas with little to
no impact on travel. Temperatures will trend below normal Friday
through the weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1257 AM CDT Mon May 12 2025

Winds will be gusty at times overnight at the terminals. Low-
level wind shear is forecast through 11-15Z. A strong south-
southwesterly jet with wind speeds around 50 knots is forecast
overnight. As the mixed layer deepens after sunrise, the jet
will weaken and the altitude of the stronger winds will
increase, ending the LLWS threat. Winds will be gusty again
Monday and should weaken around 13.02Z tonight. LLWS may
redevelop tonight.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 406 AM CDT Mon May 12 2025

Gusty southerly winds will persist along the South Shore until
around 7 AM. The cold water temperatures will continue to create
a stable boundary layer over the water farther north which will
limit the wind gust potential. Adjusted the Small Craft
Advisory to keep the South Shore waters and cancel the North
Shore waters (where conditions have improved). Beyond this
morning, the risk of hazardous conditions on the water is low
until Thursday when a low pressure system will bring strong
winds, thunderstorms, and dangerous waves to western Lake
Superior.

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

&&

.CLIMATE...
Issued at 406 AM CDT Mon May 12 2025

Record High Temperatures:

May 12:          Forecast:
KDLH: 84/1940       84
KINL: 86/1991       88
KBRD: 88/1940       91
KHIB: 86/1977       88
KASX: 90/1894       87

May 13:
KDLH: 86/1977       83
KINL: 87/1977       88
KBRD: 91/1900       91
KHIB: 90/1977       87
KASX: 90/1977       88


Record Warm Minimum Temperatures:

May 12:          Forecast:
KDLH: 56/1991       59
KINL: 55/2023       66
KBRD: 60/1991       63
KHIB: 53/1944       60
KASX: 58/1894       59

May 13:
KDLH: 54/1991       57
KINL: 55/1987       64
KHIB: 52/1987       57
KASX: 58/1987       58

May 14:
KINL: 58/1977       62
KBRD: 62/1998       62
KHIB: 54/1998       55

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Red Flag Warning from noon today to 9 PM CDT this evening for
     MNZ010>012-018-019-025-026-033>038.
WI...Fire Weather Watch from noon CDT today through this evening
     for WIZ001>004-006>009.
MARINE...Small Craft Advisory until 5 AM CDT early this morning for
     LSZ121-144>148-150.
     Small Craft Advisory until 7 AM CDT this morning for LSZ140.

&&

$$

DISCUSSION...Huyck
AVIATION...Huyck
MARINE...Huyck
CLIMATE...Huyck