059
FXUS63 KDLH 050925
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
425 AM CDT Fri Jul 5 2024

.KEY MESSAGES...

- Active pattern continues with a chance for moderate rain
  today. The greatest chance of 0.5-1.0 inches is mainly south
  of a line from the Brainerd Lakes to Moose Lake to Ashland, WI
  through noon today.

- Isolated to scattered showers and a few storms are forecast
  this afternoon, mainly over Minnesota.

- Another system will bring additional chances of rain this
  weekend. Diurnal rain and storm chances persist through much
  of next week.

- High water persists across the Rainy River Basin and a Flood
  Advisory is in effect through early next week. See the summary
  at www.weather.gov/dlh/RainyRiverBasin for more information.

&&

.DISCUSSION...
Issued at 424 AM CDT Fri Jul 5 2024

Early this morning an area of light to moderate rain, with a
few embedded thunderstorms, arced from southwest Minnesota
through central Minnesota and into northwest Wisconsin and upper
Michigan. RAP analysis revealed a stacked low was found over
southeast Minnesota and southern Wisconsin with the surface low
centered over southern Wisconsin. GOES-East WV and IR imagery
indicated the upper-level portion of the system tightly wound
with a wedge of dry air over northeast Iowa and much of
Wisconsin.

Model guidance has struggled to handle the evolution of this
system over the past several hours and is too quick to end
precipitation and push the area of low pressure to the east.
Have slowed the departure of the system in the forecast by
several hours this morning and hold onto PoPs several hours
longer than the deterministic guidance would indicate. Cloud
tops continue to gradually cool over northwest Wisconsin,
although a slight warming trend has emerged in the past half
hour or so. All indications are for precipitation to gradually
diminish as the low pressure slips to the east-southeast this
morning.

There are still periodic brief thunderstorms embedded in the
stratiform precipitation and think the potential for additional
brief storms will persist through the morning. There remains a
possibility for locally heavy rainfall due to slow storm motions
and a deep warm cloud layer. The heaviest rainfall since
Thursday afternoon has fallen in areas without automated gauges.
Therefore we`re relying on KDLH Dual-Pol Storm Total
Accumulation and MRMS-Radar Only precip estimates this morning,
which reveal a stripe of 0.5 to over 4 inches of rain since
Thursday morning from southern Cass to northern Pine County.
Rainfall amounts over northwest Wisconsin have ticked upward
over the past six hours and are now generally in the few tenths
to nearly 2 inches. The few spotter reports we received seem to
match up well to the radar estimates. Flood Advisories are in
effect from southern Cass County to northern Pine County and we
received a few reports of minor flooding. Think the water levels
are likely decreasing over the advisory areas and we will be
able to let those headlines expire by 14Z.

Attention then shifts to this afternoon. Partial sunshine over
northern Minnesota, along with weak cold air advection and
cyclonic flow aloft, will support isolated to scattered showers
and a few thunderstorms this afternoon and early evening. Latest
CAM guidance keeps the precipitation limited to Minnesota,
although a few showers may slip into the St. Croix River Valley
this evening before diminishing. Temperatures today will vary
with north-central Minnesota seeing upper 70s and north-central
Wisconsin only in the upper 60s.

A shortwave trough is forecast to propagate eastward across the
Northland on Saturday. Relatively cool air aloft will support
another round of diurnal showers and thunderstorms during the
late morning through evening. MLCAPE values are forecast in the
500-1000 J/kg range although deep layer shear will be very weak,
less than 20 knots. Showers and storms should develop and
collapse over a short time period. Subsequent outflow boundaries
will become the main mechanism for sustained convection through
the afternoon. Small hail is not out of the question with any
sustained storms.

Diurnal shower and storm chances will be the norm through most
of next week. Models are trending toward a dry day or two
perhaps Wednesday and/or Thursday.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 119 AM CDT Fri Jul 5 2024

A band of rain with a few embedded thunderstorms stretched from
near AXN to BRD and AIT to RHI early this morning and should
persist and gradually shift eastward with time today. There`s a
small chance a few showers move into DLH before 14Z. Forecast
guidance continues to show decreasing ceilings at HYR through
12Z. IFR conditions are possible. For now went with MVFR
ceilings. Additional showers and storms will percolate this
afternoon over central and northern Minnesota. Backed off the
VCTS mentions in favor of VCSH. A storm or two may affect the
terminals, however, it seems predictability is lower than would
warrant prolonged periods of VCTS for now.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 424 AM CDT Fri Jul 5 2024

Northeast winds of 5 to 10 knots were reported over western
Lake Superior this morning. An area of surface low pressure was
centered over southern Wisconsin and will move east-
southeastward today allowing the pressure gradient over the lake
to relax and wind speeds to gradually diminish. Winds will back
northerly by this afternoon and southwesterly overnight. Wind
speeds will remain relatively light, in the 5 to 15 knot range,
through the weekend. Aside from a small risk of a few
thunderstorms, no hazardous weather is expected.

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

&&

.HYDROLOGY...
Issued at 119 AM CDT Fri Jul 5 2024

No updates with this issuance... Previous discussion below.

A Flood Advisory remains in effect across portions of the Rainy
River Basin, extending as far east as Lac La Croix and as far
west as the Rainy Lake outlet. Lingering high water from June
and early July rainfall continues to flow slowly through the
Rainy River Basin. Headwaters gauges on the Kawishiwi River,
Basswood River, and Lake Vermilion have crested and indicate
that the flood wave or peak water levels are slowly making their
way through the basin. However, rises continue on the Vermilion
River and Lac La Croix and downstream of those points. This has
led to high water and some minor flooding on Crane Lake and
Namakan/Kabetogama (Nam/Kab) lakes, as well as lake levels
increasing on Rainy Lake.

Per the latest IJC water level bulletin, dam operators have
pulled all logs at Kettle and Squirrel Falls, and continue
pulling logs at International Falls as conditions allow in order
to maximize outflow through the basin. However, the sheer
volume of water moving through the basin will still result in
rises on these lakes due to the natural constriction of the
flow. Vermilion River is forecast to crest late this week and
then begin slow recessions. Water level rises further downstream
on Nam/Kab are likely to continue (recent rates of rise have
been an inch or two a day, this is likely greatest rates of rise
and should begin to slow by the weekend), with peak water level
early to mid next week. As is usual for this basin, water will
move slowly and recessions will happen at glacial speeds.
Additional rainfall may cause brief rises in tributaries and
extend the period of high water in core lakes. Boaters should
expect high water, potentially hidden underwater hazards, and
strong currents in constricted areas.

The Flood Advisory currently extends through next Wednesday,
but may need to be extended based on observed conditions.

&&

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

&&

$$

DISCUSSION...Huyck
AVIATION...Huyck
MARINE...Huyck
HYDROLOGY...Huyck/Levens