401
FXUS63 KDLH 082010
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
310 PM CDT Mon Jul 8 2024

.KEY MESSAGES...

- Afternoon showers and storms once again will dissipate shortly after
  sunset. No severe weather is expected but some brief heavy
  downpours with pea sized hail is possible.

- Patchy dense fog will be possible in the morning once again with
  visibilities dropping to less than 1/2 mile.

- Similar conditions for tomorrow with storms firing off in the afternoon
  once again. Smokey skies aloft will also enter due to
  Canadian Wildfires.

- Temperatures trends for this weekend look warm with highs
  climbing into the 90s. A Heat Advisory may be needed for the
  Brainerd Lakes Region.

&&

.DISCUSSION...
Issued at 307 PM CDT Mon Jul 8 2024

Current Conditions/Today:

Broad upper level troughing persists across the Upper Midwest this
afternoon. Satellite reveals blossoming cu fields with radar
indicating thunderstorm cells filling in across the Arrowhead and NW
WI. Like we have seen for the past several days these storms are
largely diurnally driven and will be scattered in nature. Lack of
upper level flow will lend itself to no severe storms. Instability
is somewhat notable with MLCAPEs of 1000 J/kg. This should be
enough to generate some pea sized hail at times but lack of storm
tilt this afternoon will lead to shallow storms collapsing on
themselves. The only other concern with these storms is some
minor flooding. Surface streamlines highlight a corridor of good
convergence south of Sawyer where training storms have been
ongoing. Depending on how this line shifts it may impact our
CWA. Storm activity quickly diminishes after sunset and
overnight could see some patchy fog develop once again. High res
guidance suggests a 40-60% chance of fog reducing visibility to
less then a half a mile.

Tomorrow:

Rinse and repeat of the previous day. Upper level trough with
cyclonic flow aloft paired with the summer sun and PWATs of over an
inch will lead to pop up thunderstorms in the afternoon. The same
convective parameter space still applies. Negligible shear but
modest instability producing scattered storms some capable of small
hail and brief heavy downpours. Activity wanes after sunset and some
patchy fog in the morning can`t be ruled out.

Smoke/Tuesday:

Wildfire smoke from Canadian fire in northern British Columbia and
Alberta may slide through the Northland over the next several days.
The HRRR smoke model keeps the majority of the smoke aloft with a
few pockets mixing down to the surface at times. The higher
concentrations aloft look to move in Tuesday. Afternoon rain showers
could help pull some of this concentration to the surface. Currently
the MPCA has the northern MN highlighted in a "high end" moderate
for AQI. No Air Quality Alerts at this time.

Midweek into the weekend:

Wednesday could see some additional diurnally driven storms in the
afternoon once again. Upper level ridging starts to push in from the
west Thursday with dry air pushing in from Canada. Thursday will be
a precipitation free day with highs starting to climb into the upper
80s. This warming trend continues into the weekends with highs
climbing into the 90s for portions of the Northland. Min T`s for the
weekend won`t offer too much in heat relief either with lows staying
into the 60s. A Heat Advisory may be needed for the weekend, most
likely in the Brainerd Lakes Region. There may be a return of severe
weather this weekend as well with the CSU probabilities starting to
move into the Northland. However, there still remains a fair bit of
disagreement among the 12Z suite of guidance.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1223 PM CDT Mon Jul 8 2024

Diurnally driven cumulus clouds are starting to show growth this
afternoon on satellite with some storm initiation over NW WI. It is
another similar set up as the previous day with pop up storms
scouring the Northland with activity waning after sunset. No severe
weather expected put some brief heavy downpours with small hail will
be possible. Some patchy fog will also be envelope the Northland
tomorrow morning with 30-50% chance of LIFR visibilities.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 307 PM CDT Mon Jul 8 2024

Light winds through the forecast period. Main item of note is the
diurnally driven thunderstorms that have popped up this afternoon.
This activity will wane after sunset and no severe weather is
expected. Expect additional round of thunderstorms to populate in the
afternoon for Tuesday and Wednesday.

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

&&

.HYDROLOGY...
Issued at 401 AM CDT Mon Jul 8 2024

A Flood Advisory continues across portions of the Rainy River
Basin, extending as far east as Lac La Croix and as far west as the
Rainy Lake outlet. This advisory has been extended through
Friday, but as headwaters level begin to crest, may be trimmed
in its areal extent through the week. Lingering high water from
rains in June continue across the Rainy River Basin. Far
headwaters gauges on the Kawishiwi River, Basswood River, and
Lake Vermilion have crested and are slowly but surely coming
down, but remain elevated (Lake Vermilion still a foot above its
pre-rain level). The Vermilion River continues to fall once
again, falling at a rate of a couple inches each day, and the
River Flood Warning may be able to be canceled in the next day
or two should these recessions continue. This has allowed the
lake level increases on Crane Lake to slow considerably, with
less than an inch of rise in the last 24 hours. Lac La Croix
levels are beginning to show signs of cresting, as rises in the
last day have been less than an inch as well (around 2cm), after
some much faster rates of rise earlier this month. All this
high water continues to lead to steady rises on downstream
lakes, notably Namakan/Kabetogama (Nam/Kab) lakes where minor
flooding continues, and on Rainy Lake where levels are high but
no flooding is ongoing, per latest reports and webcams. Per the
latest IJC water level bulletin, dam operators are working to
maximize outflow through the basin. However, the sheer volume of
water moving through will still result in additional rises on
these lakes. As water levels upstream crest and begin to come
down, rates of rise on Nam/Kab should begin to slow and
eventually crest, and levels continue. We`ve already seen the
rates of rise begin to demonstrate signs of slowing. From July 1
to 3rd, Nam/Kab Lakes were rising at 2- 2.5" per day, but have
slowed to 1-1.5"/day over the weekend. General guidance suggests
peak levels on Nam/Kab could be possible this week, but that is
uncertain. 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 (including
submerged docks), and strong currents in constricted areas.
Generally light winds are expected, except for possible brief
erratic gusts out of thunderstorms, so wave heights should
remain fairly minimal.

&&

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

&&

$$

DISCUSSION...Britt
AVIATION...Britt
MARINE...Britt
HYDROLOGY...Levens