304
FXUS63 KDLH 172350
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
650 PM CDT Fri May 17 2024

.KEY MESSAGES...

Key Messages:

- Scattered showers and some storms through the rest of today

- Marginal Risk for severe storms on Saturday with large hail up
  to quarter size and gusty winds being the biggest concern

- Quick dry spell before our active weather pattern returns next
  week with multiple shots for rain

&&

.DISCUSSION...
Issued at 326 PM CDT Fri May 17 2024

Short Term:

As of early afternoon, some weak reflectivity returns can be
seen on radar across the Minnesota Arrowhead. This is tied to a
weak vorticity maxima swinging through the region which is
causing some weak ascent ahead of it. This has led to showers
and drizzle in areas close to the Canadian Border. This should
continue to push northward and out of the area in the next few
hours. Following this, clear skies should be present with highs
topping off in the mid to upper 70s across much of the region.
Areas closer to the lake will stick in the 50s and 60s due to
the presence of a lake breeze slowly moving inland. Through this
afternoon and evening, there is a low end chance (30-40%) of
some showers and storms refiring across our CWA. Some of these
showers could be a bit stronger than the ones we saw this
morning with some lightning possible and stronger gusts at
times. Some scattered showers will persist overnight as we get
strong isentropic advection from the south.


Mid-Range:
Our eyes turn to tomorrow and the threat of storms across our
CWA as a cold front sweeps through the area. As it stands right
now, the SPC has put the eastern half of our CWA in a Marginal
Risk (Level 1/5) for severe weather tomorrow. The main threats
would be large hail up to quarter size and gusty winds up to
60mph within the stronger convection. A trough swinging through
the Canadian Prairies tonight will reach our area late Saturday
Afternoon. Itll induce cyclogenesis of a surface cyclone
thatll advect moisture into the area pushing dewpoints into the
upper 50s and even lower 60s by mid afternoon. The result of
these two things is anywhere from 500-1500 joules of MUCAPE to
form by afternoon with 40-50kts of Bulk Shear in our vicinity.
This will lead to organized convection forming in the early
afternoon near the I-35 Corridor before overspreading further
east through the rest of the evening. Following the cold front,
Sunday should be mostly dry with high topping off in the low to
mid 70s with a light westerly wind to top it off.

Extended Range:
The quick dry spell will quickly end as we begin the workweek
with a quick moving shortwave moving through the Northern Plains
on Monday. While nothing too substantial is expected out of it,
we could see some scattered showers and thunderstorms across the
CWA during the daytime on Monday. As that moves out of the
region Monday afternoon, a more notable and impactful system
will ride into the Northern Great Lakes by Tuesday morning.
While we wont see many convective storms being north of the
surface low, we will mainly see a prolonged period of rain. The
rain which could be heavy at times will lead to QPF totals in
excess of 0.5-1.5 in a 24 hour time frame. We should see
quieter conditions arrive following this storm to close out the
work week.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 650 PM CDT Fri May 17 2024

Isolated thunderstorms currently around the Iron Range and
northern Aitkin County will continue to move east towards DLH
this evening. Additional showers and thunderstorms are
anticipated to arrive tonight into tomorrow along a cold front.
Recent model runs were showing an increasing trend for MVFR fog
in DLH early Saturday morning, so a mention was included in this
update. Low-level wind shear will be a concern tonight for all
terminals, especially on the MN side of the region. Expect a
line of showers and thunderstorms to move through the area
tomorrow along the cold front, bringing the potential for MVFR
cigs and visibility. After the cold frontal passage, conditions
will be improving to VFR with decreasing cloud cover.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 326 PM CDT Fri May 17 2024

Issued a 6-hour Small Craft Advisory from Duluth to Sand Island
as winds have gusted to around 25 kt at Port Wing the past
couple observations. Winds are expected to lessen gradually this
evening, but some higher waves up to 4 ft could linger.
Otherwise, northeast winds lessen tonight, then gradually shift
to southwest on Saturday as a cold front passes through. Some
stronger wind gusts approaching 20-25 kt may be possible around
the head of the lake Saturday afternoon. A Small Craft Advisory
may be needed. Scattered showers and thunderstorms are possible
overnight (30% chance), then some strong to low- end severe
storms are possible through Saturday afternoon (50-70% chance of
storms and 5-10% chance for strong to severe storms capable of
producing strong winds to 50 kt and large hail up to quarter
size).

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...Small Craft Advisory until 10 PM CDT this evening for LSZ145-
     146.

&&

$$

DISCUSSION...JDS
AVIATION...Unruh
MARINE...JDS