911
FXUS63 KDLH 302353
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
653 PM CDT Tue Apr 30 2024

.KEY MESSAGES...

- Rain and thunderstorms are expected tonight into Wednesday
  morning.

- Another series of rainy systems are expected Thursday into
  Friday and again Friday night through Saturday evening.

- Temperatures gradually warm up through this weekend.

&&

.DISCUSSION...
Issued at 235 PM CDT Tue Apr 30 2024

We are nestled underneath a brief ridge this afternoon that has
opened up the skies for a little bit of sunshine in some places. The
next rain maker will arrive tonight in the form of a negatively
tilted upper level trough with what will essentially end up
manifesting itself at the surface as an occluded front with
some forerunning elevated CAPE (up to 300 J/kg or so) mainly in
NW Wisconsin. Lapse rates become around 7 C/km tonight as well,
which will be favorable for some elevated thunderstorms. The
highest moisture will also be found across northwest Wisconsin,
where PWATs approaching around 1" will be hitting around 90th
percentile of climatology, and still reaching between 0.75" and
1" further north. All-in-all, the forecast is looking consistent
for a widespread 0.40"-0.90" of rainfall with some locally
higher amounts up to 1"- 1.25" possible mainly in northwest
Wisconsin. Timing-wise, rain should move in from the southwest
late this afternoon, hitting the Brainerd Lakes around 6 PM,
then spreading northeast through the night, and exiting to the
northeast through Wednesday morning.

After the rain ends Wednesday morning, some drier westerly flow will
set up with upper level ridging, allowing for some blustery
conditions and sunshine. With plenty of low-level mixing and the dry
air mass moving in, min RH may fall to around 35-40%, but fire
weather conditions are expected to be minimal due to recent
rains.

The active weather pattern continues for the later part of the week
as a broad trough deepens as it passes over the Rockies. Southerly
flow ahead of this trough will tap into more Gulf of Mexico moisture
and bring some more organized rain chances to the region Thursday
into Friday. Better chances for any severe weather should remain to
our south where the best instability and frontogenesis is likely to
be as a broad cold front develops. The low center is likely to be
deepening over our region, so we`ll likely be dealing with more
synoptic rainfall with a few embedded non-severe thunderstorms (best
chances over northwest Wisconsin...similar to tonight`s setup). How
much moisture we end up remains in question, and ensembles are all
over the place with potential rainfall amounts, but right now we`re
looking at a 60-80% chance of rain Thursday into Friday with PWATs
potentially reaching into that 0.75"-1" range. I wouldn`t say this
system will be a mirror image of tonight`s rainmaker, but it
certainly seems to share many synoptic similarities the way things
look now.

There may be a brief break in rain Friday afternoon and night, but
models are starting to come into some agreement that a weaker trough
may follow as we head into Saturday and Saturday night and bring
some more rain to parts of the region.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 634 PM CDT Tue Apr 30 2024

A line of rain showers are moving north this evening and
tonight. Models have been overzealous with the lowering thus
far, so tried to delay lowering ceilings by a few hours for BRD,
DLH and HIB. Ceilings are expected to lower later tonight,
however, and will likely (60-70%) lower to LIFR in the late
overnight hours. MVFR visibilities have been seen with this rain
across southern and central Minnesota, so reflected that in the
TAFs as well. There is a small chance for thunderstorms, but is
less than 20% so opted to leave thunder out of the TAF. Fog is
possible tonight, with some terminals getting visibilities as
low as IFR, but should recover quickly by morning.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 235 PM CDT Tue Apr 30 2024

Gusty northeast winds are expected to develop fairly quickly
this evening as rain moves in and will persist through the
night. Gales don`t appear likely, but a very brief gale-force
gust can`t be completely ruled out. Winds will quickly shift to
northwest Wednesday morning and some gusty winds and high waves will
persist through the day. Small Craft Advisories have been
issued. Winds are expected to lighten up Wednesday night. The
next chance for stronger winds will be on Thursday with another
rainy system moving in.

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

&&

.CLIMATE...
Issued at 235 PM CDT Tue Apr 30 2024

Taking a step back and looking at the broader picture, a generally
wavy upper-level pattern looks to persist into the 8-14 day period,
though perhaps becoming slightly less amplified per the Climate
Prediction Center (CPC) outlook discussion. We may maintain a
pattern of on-and-off rain chances going into early-to-mid May as a
result, which should generally be good news for drought conditions
that have been persistent up until the past couple weeks. In the
past 14 days, around 1-3 inches of rain has fallen (locally higher),
which is as much as 150-300% of normal. The CPC 8-14 day outlook
(May 7-13) favors slightly above normal chances for precipitation,
and drought conditions are expected to improve or perhaps even end
for many parts of the region with plentiful rainfall we have
received and more chances yet to come.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...Small Craft Advisory from 10 PM this evening to 10 AM CDT
     Wednesday for LSZ140>142.
     Small Craft Advisory until 10 AM CDT Wednesday for LSZ143.
     Small Craft Advisory until 4 AM CDT Wednesday for LSZ144-145.
     Small Craft Advisory from 10 PM this evening to 4 PM CDT
     Wednesday for LSZ146-147-150.
     Small Craft Advisory from 10 PM this evening to 4 AM CDT
     Wednesday for LSZ148.

&&

$$

DISCUSSION...JDS
AVIATION...KML
MARINE...JDS
CLIMATE...JDS