Area Forecast Discussion
Issued by NWS Duluth, MN

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674
FXUS63 KDLH 021734
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1234 PM CDT Tue Jul 2 2024

.KEY MESSAGES...

- Areas of heavy rain has occurred over portions of far northern
  Minnesota, mainly across parts of Koochiching, northern St.
  Louis, and far northwest Lake Counties. The Flood Watch
  continues there as runoff works its way into rivers and
  streams.

- Showers and a few thunderstorms this morning will end from
  southwest to northeast with additional isolated to scattered
  showers/storms this afternoon and early evening.

- More rain expected later Thursday into Friday and it could be
  heavy, especially over southern portions of the Northland.

&&

.DISCUSSION...
Issued at 342 AM CDT Tue Jul 2 2024

A southerly 45 to 50 knot jet continued this morning and was
aiding in producing showers and a few thunderstorms. Instability
was meager at best and only a few thunderstorms are expected
this morning. Heavy rainfall has occurred over portions of
Koochiching, northern St. Louis, and far northwest Lake
Counties. Observations show amounts from 1 to 2.5" as of 3AM.
Showers continued across much of the Northland but were ending
over southwest portions. Additional rainfall this morning will
be up to a half inch. We cancelled the Flood Watch for all but
Koochiching, Northern St. Louis, and inland Lake/Cook Counties.
Runoff from the heavy rain will be working through rivers and
streams today. The low level jet will shift east and veer to
southwest through this morning. Prior to that, isolated higher
gusts of 30 to 40 mph will be possible, mostly likely over
northwest Wisconsin.

A frontal boundary extended south out of low pressure in
southern Manitoba through the Red River Valley into Nebraska
this moving. After the showers move off or diminish in coverage
this morning, additional development will occur this afternoon,
especially ahead of the frontal boundary. CAPE will increase to
400 to ~1000j/kg so a few thunderstorms will occur as well.
Coverage of the showers/storms are not expected to be widespread
so additional widespread heavy rain is not expected.

Showers/storms will end tonight and it should be dry into
Wednesday morning for most. There is a chance for a few
showers/storms to develop Wednesday afternoon over much of the
Northland and we have 20-30% POPS going over all but far
southern portions. Highs Wednesday will be from the lower
seventies to around eighty.

A stronger shortwave will arrive on Thursday with a surface low
forming. There is general consensus among the deterministic
models that the upper wave and surface low will move through
southern Minnesota or northern Iowa and Wisconsin Thursday into
Friday. ECMWF ensemble members show a significant spread in low
track. There is potential for heavy rain over portions of the
Northland, with southern areas favored at this time. There is
some instability to work with too although PWAT values are a
bit lower, around 1.4", compared to the current system. The NBM
has 30-50% chance for rainfall of 1" or greater Thursday into
Friday night from east central Minnesota into northern
Wisconsin.

An upper ridge will build over the western CONUS/western Canada
over the weekend with north/northwest upper flow over the
Northland. A couple more shortwaves will dive southeast and
bring rain chances but these system will be more progressive.

Temperatures will be seasonal through much of the period with
cooler temperatures occurring Friday over southern areas which
will see the highest chances for rain.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1226 PM CDT Tue Jul 2 2024

An area of LIFR to IFR sky cover exits north-central Minnesota
over the next hour or two, while lasting into northeast
Minnesota and northwest Wisconsin through 00Z today. Showers
increase again from west-central Minnesota into the Brainerd
Lakes around 21Z and into northeast Minnesota through 05Z.
Isolated thunderstorms are most likely near HIB and INL this
evening. Overnight mist may setup to create MVFR to IFR
visibility at some terminals. West-northwest winds create gusty
conditions daytime Wednesday.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 342 AM CDT Tue Jul 2 2024

Southerly winds are expected today, from 10 to 15 knots with
gusts to 20 knots for most areas. However, stronger winds aloft
may mix down at times creating stronger winds with gusts to 30
knots. This is most likely from the Twin Ports and South Shore
and we issued a Small Craft Advisory there into this afternoon.
A few thunderstorms will be possible today, mainly this
afternoon and evening.

The wind will veer to southwest tonight and be at 15 knots or
less. West or southwest winds will strengthen Wednesday to 10 to
20 knots with higher gusts and Small Craft Advisories will
likely be needed over portions of the nearshore waters.

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.

&&

$$

DISCUSSION...Melde
AVIATION...NLy
MARINE...Melde