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000
FXUS63 KDLH 121747
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1247 PM CDT Fri Apr 12 2024

.KEY MESSAGES...

- A large, warm, and wet system is forecast to move through the
  Upper Midwest Monday-Thursday, with the potential for
  thunderstorms and heavy rain increasing. Snow is expected on
  the backside of this system.

- Dry and windy conditions are expected Sunday and may cause
  near-critical fire weather conditions.

- A clipper system on Saturday night brings a chance (20-40%)
  for light rain.

&&

.DISCUSSION...
Issued at 259 AM CDT Fri Apr 12 2024

In between systems today before the next clipper slides by on
Saturday for some small chances for meager light rain and
largely non-eventful weather.

Dry air will follow the clipper and slide across dropping RH`s
down into the 20s with wind speeds still elevated giving some
concern for fire weather both late Saturday and Sunday. RH will
be lower on Sunday, but winds will be higher on Saturday. May
need a special weather statement for this if fuels dry out
enough.

Not much change in the details of the large system next week
though the the one fairly significant change is that the GEFS
are trending up on the snowfall potential Wednesday night into
Friday. The Euro and Canadian model camps aren`t as aggressive
with this, but still have some accumulating snow signature.

The overall gist of the system remains the same. On Monday a
LLJ, sneaks into the area in concert with abundant shear,
climatologically high values of PWATs (1.2"), and a strong Fgen
signal all combining to usher in warm air and sufficient lapse
rates giving a shot for thunderstorms and heavy rainfall. These
parameters further grow in magnitude as an expansive low
pressure spawns over the Great Plains and deepens to a 985 mb
low somewhere over MN/WI. Strong jet dynamics and a negatively
tilted trough all play into this strongly forced system which
should provide large amounts of synoptic lift causing rain with
periods of thunderstorms. By Thursday, the system begins to
exit, but pulls down cold air and may produce accumulating
snowfall though it`s still a bit early with the specifics for
this. Guidance among model solutions begins to diverge with the
handling of the cold air timing on the systems exit. Overall,
ensemble guidance is fairly clustered lending higher confidence
to the deterministic solutions. Long story short, keep an eye on
the forecast as this system will likely bring some hazards to
the Northland. The drought conditions will buffer most of the
potential impacts of flooding from this system, but not
completely preclude them. The WPC has portions of the Northland
in a Marginal risk for Flash Flooding on day 4 and 5. The SPC`s
severe threat remains south of our area as the good instability
doesn`t get too far north.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1247 PM CDT Fri Apr 12 2024

Some broken MVFR ceilings at DLH/HIB/HYR are expected to
gradually mix out to VFR this afternoon. Breezy conditions with
gusts to 20-25 kt from the north/northwest will continue this
afternoon, then decrease leading into sunset. Dry air moving in
tonight will lead to mostly clear skies and winds will become
light and variable tonight, then southerly on Saturday.

&&

.MARINE...
Issued at 259 AM CDT Fri Apr 12 2024

Fairly robust pressure gradient remains today as an area of low
pressure to our east slowly leaves. This gradient is causing
northwest winds gusting to 25 to 30 knots. The gradient will
relax tonight giving light winds. The next system will approach
from the west increasing easterly winds and waves Saturday
afternoon.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...Small Craft Advisory until 5 PM CDT this afternoon for LSZ121-
     144>148-150.
     Small Craft Advisory until 9 PM CDT this evening for
     LSZ140>143.

&&

$$

DISCUSSION...Wolfe
AVIATION...JDS
MARINE...Wolfe