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000
FXUS63 KDLH 152331
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
631 PM CDT Mon Apr 15 2024

.KEY MESSAGES...

- Low humidity this afternoon across most of the Northland
  creating elevated fire weather conditions. Near-critical fire
  weather conditions are expected once again in spots Tuesday,
  mainly over portions of northwest Wisconsin into far northern
  Minnesota.

- An area of low pressure will bring rain chances to the
  Northland Tuesday into Wednesday with lower chances lingering
  Thursday into Friday. A light wintry mix will be possible in
  spots, mainly over the Arrowhead but little significant
  snowfall is expected.

- Total rainfall amounts appear to have stabilized with this
  forecast, but remaining on the lower side. Forecast amounts
  range from a quarter inch up to one inch from Tuesday into
  Wednesday night. There is a 40 to 70 percent chance for
  amounts exceeding one inch for most of northwest Wisconsin,
  the North Shore and the I-35 corridor in Minnesota, with even
  lower probabilities elsewhere.

&&

.DISCUSSION...
Issued at 422 PM CDT Mon Apr 15 2024

We have had yet another dry day today, with afternoon minimum
RH values down in to the 15 to 25 percent range this afternoon.
Some weak showers have been flirting with the Brainerd Lakes
area this afternoon, with cloud bases around 9kft and
visibilities at or above 10sm. I expect this trend to continue
tonight, with rain showers drifting along our western and
southwestern border overnight, with the low level dry air
helping to keep a lot of this precipitation to our southwest.

Tuesday the main upper low and accompanying moisture surge
should push into the area from the south, even as the surface
low deepens as it moves across Nebraska. Models are in good
agreement on pushing an area of rain with some embedded
convective elements into the forecast area during the morning,
then spreading slowly northeast during the afternoon and evening
hours. The best lift, from isentropic lift and warm air
advection slides across the forecast area overnight Tuesday
night, then slowly pivots over the area Wednesday before pulling
to the northeast Wednesday night. PWAT values will rise to
0.75-1.00 inches Tuesday/Tuesday night which is in the 90th
percentile but not too extreme. Once again, we have slowed the
progression of the rain to the north on Tuesday due to the
presence of drier air out of the high well off to the northeast.
Instability is quite limited with this system so the chances
for thunderstorms have diminished and the threat for heavy
rainfall has also diminished. The chance for 48 hour rainfall
exceeding 1 inch Tuesday through Wednesday night ranges from 40
to 70%, highest from the St. Croix River Valley into northwest
Wisconsin, as well as along the North Shore.

Strong winds are still looking likely starting Tuesday and
diminishing through the day Wednesday. Easterly gusts of 30 to
40 mph are expected Tuesday afternoon and early evening,
strongest around Lake Superior. The strong wind will continue
Tuesday night then diminish through the day Wednesday.

Thursday should have some decent low level lapse rates during
the daytime, so while the models do not have much for
precipitation across the area, we should have some diurnally
driven showers, mainly during the afternoon hours. There is a
fairly significant surge of cold air moving in Thursday and
Thursday night, which combined with moisture sagging into the
area from the north should make Friday our coldest day on the
back side of our mid-week system. Steep low level lapse rates
once again on Friday should produce afternoon showers, but
perhaps not as widespread as we should see Thursday. A trough
axis swings across the forecast area on Saturday with the cold
pool still in place aloft may keep the small pops lingering.
Temperatures warm slightly, but not all that much warmer than
Friday.

Sunday into early next week is a fairly significant spaghetti
mess at upper levels, with some hints in the cluster analysis of
a shortwave that moves over the top of the weak ridge over the
western CONUS. However, there is a large spread in the location,
track and strength of this feature, and have low confidence in
any precipitation chances beyond Sunday. Temperatures should be
near normal into early next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 630 PM CDT Mon Apr 15 2024

VFR conditions continue for most terminals through the TAF
period. Showers continue to attempt to move into BRD early this
evening, but substantial dry air in the low levels of the
atmosphere has prevented rain from reaching the ground. Easterly
winds begin to increase tonight, and become much stronger
tomorrow morning through the end of the TAF period. Low-level
wind shear remains a concern tonight into Tuesday morning,
mainly at BRD and HYR before winds and gusts strengthen more on
Tuesday. MVFR ceilings and visibilities begin to work into BRD
later tomorrow afternoon with rain showers beginning to spread
northeast across the region, but some initial dry low-level air
should delay the start of the rain for most of the Northland
until late Tuesday afternoon/evening.

&&

.MARINE...
Issued at 422 PM CDT Mon Apr 15 2024

Winds will be at or less than 15 knots this evening, and
generally easterly in the southwest arm of the lake, and
southerly for the more open waters portions of the lake. Winds
become a more consistent east tonight and increase into Tuesday
and Tuesday night as a strengthening area of low pressure moves
into the Central Plains. East/northeast winds will increase into
the 15 to 25 knots Tuesday morning, strengthening still further
during the day, until we are getting gales over a large portion
of the lake from late morning through Tuesday late evening,
when wind speeds are at their maximum. Chances for gales have
increased enough that we have issued a Gale Warning for much of
the nearshore waters beginning Tuesday morning and continuing
until early Wednesday morning. There is also about a 6 hour
Small Craft Advisory in advance of the Gale Warning Tuesday
morning as wind speeds increase. More Small Craft Advisories
will be needed after the Gale Warnings expire, potentially
continuing through Thursday.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...Small Craft Advisory from 10 AM Tuesday to 4 AM CDT Wednesday
     for LSZ121.
     Small Craft Advisory from 4 AM to 10 AM CDT Tuesday for
     LSZ140>147-150.
     Gale Warning from 10 AM Tuesday to 4 PM CDT Wednesday for
     LSZ140>142.
     Gale Warning from 10 AM Tuesday to 10 AM CDT Wednesday for
     LSZ143>147-150.
     Small Craft Advisory from 10 AM Tuesday to 4 PM CDT Wednesday
     for LSZ148.

&&

$$

DISCUSSION...LE
AVIATION...Rothstein
MARINE...LE