481
FXUS63 KDLH 192141
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
441 PM CDT Wed Jun 19 2024

.KEY MESSAGES...

- Chances for showers and thunderstorms return to the area
  Thursday into Thursday night.

- Several rounds of rain and storms are forecast Friday through
  the weekend. A few strong storms are possible and there is a
  risk of additional heavy rain.

- The greatest risk of additional heavy rain is generally south
  of a Walker to Duluth to Bayfield, WI to Wakefield, MI line
  including all of NW WI Friday night through Saturday.

&&

.DISCUSSION...
Issued at 440 PM CDT Wed Jun 19 2024

High pressure over the region this afternoon will provide a
respite from the active weather of the past week or so before
drifting northeastward into Ontario Thursday and Thursday night.
Persistent southwest flow aloft will include a surge of
moisture and a ripple in the height fields late tonight and
Thursday. Diffluence aloft and ascent supported by 700-600 mb
frontogenesis should generate an area of showers from western
Minnesota into central Minnesota by 7 AM Thursday. Dry air aloft
below the cloud-bearing layer will translate into widespread
radar echoes, though a smaller footprint of rain reaching the
ground. Have included a chance of sprinkles overnight after 06Z.
Rain chances increase through the day Thursday, except over far
northern portions of Minnesota, generally north of the Iron
Range. Isentropic ascent will be aided Thursday night into early
Friday by a passing shortwave trough and 850 mb convergence on
the nose of a weak low-level jet.

As the high pressure departs, a warm front will lift northward
across the Midwest to near the Iowa/Minnesota border by 12Z
Friday and to eastern South Dakota across central Minnesota and
northern Wisconsin by 12Z Saturday. Isentropic ascent north of
the front will continue to support shower chances and a few
thunderstorms Friday and Saturday. The position of the warm
front will serve as the northern edge for any severe weather
threat Friday and Saturday, keeping the greatest potential for
strong to severe weather south of our forecast area. A few
strong to severe storms are not out of the question,
particularly near and a little north of the boundary late Friday
night and Saturday.

The greatest potential for excessive rainfall will be Friday
night through Saturday, with the highest risk generally south
of a Hinckley, MN to Mercer, WI line. WPC added a "Moderate"
risk of excessive rain to much of the southern half of Minnesota
and a sliver of west-central and northwest Wisconsin this
afternoopn. Considering the placement of rainfall from the past
week, this seems appropriate. The areas most likely to see
heavy rain Friday night through Saturday already received
considerable rainfall over the past week.

A shortwave trough will propagate eastward out of the Rockies
Friday night and across the Plains on Saturday, which will kick
the baroclinic zone over the Upper Midwest eastward Saturday
night and Sunday. The risk of heavy rainfall will decrease
thereafter with a more progressive pattern forecast. There will
be additional rain and storm chances next week, roughly every
other day. The risk of additional flooding will decrease despite
the rain chances since the flow will be more progressive than
the stagnant baroclinic zones over the past week.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1240 PM CDT Wed Jun 19 2024

VFR ceilings are expected for the rest of the afternoon into
this evening with northwest winds. There is a small risk of fog
developing at INL, HIB, BRD, and HYR tonight. The mitigating
factor for any fog chances will be the arrival of high clouds.
As high pressure departs to the northeast overnight and
Thursday, look for high clouds to return. Rain chances increase
after 20.18Z.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 440 PM CDT Wed Jun 19 2024

A few wind gusts to 25 knots remain possible along the
immediate shoreline of the North Shore this evening. High
pressure over the region will gradually lift northeastward
tonight and Thursday. Winds will turn northeasterly by Thursday
afternoon and wind speeds will increase. Look for sustained
winds of 5 to 15 knots with gusts of 10 to 20 knots. The
strongest winds will be near the Twin Ports. Winds weaken
Thursday night. A diurnal strengthening of the northeast winds
will continue Friday and Saturday. Winds will back northwesterly
by Sunday. Small Craft Advisories may eventually be needed near
the Twin Ports should wind and waves increase above current
forecasts. Shower and storm chances return Thursday and persist
through the weekend. Some storms may be strong to severe. Heavy
rainfall is likely, particularly Friday night and Saturday,
which may reduce visibility to less than 1/4 mile at times.

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...Huyck
AVIATION...Huyck
MARINE...Huyck