River Flood Warning 27, NWS Green Bay, WI

Area Forecast Discussion...UPDATED
National Weather Service Green Bay WI
755 PM CDT Wed Apr 17 2019

New Information added to update section

.UPDATE...
Issued at 750 PM CDT Wed Apr 17 2019

Precipitation ahead/north of the frontal wave now approaching SW
Wisconsin continues to lift through the area. The highest totals
thus far have been from central Wisconsin, with 1.89 inches at
KMFI. That's leading to some ponding of water in low spots on
roads and in low-lying areas, hence the USSFA. Luckily, the
upstream returns are not that impressive and moving fairly
quickly.

The warm front is having a tough time making northward progress
into the rain/lake cooled air over most of Wisconsin. It currently
extends from south of KLNR to KBUU in southern Wisconsin. The
stronger southwest winds above the frontal boundary have
occasionally mixed down with the heavier convective precipitation,
but gusts have generally only been around 20 knots when that
happened.

Looks like any significant rainfall will move through in the next
2-3 hours. It's possible be may need an additional Flood Advisory
this evening, otherwise the main issue will become how the rivers
react to the runoff from the rainfall during the next 12-48
hours. &&

.SHORT TERM...Tonight and Thursday
Issued at 246 PM CDT Wed Apr 17 2019

The latest analysis and satellite/radar imagery show an area of
low pressure over northeast Iowa and a warm front extending
southeast across northern Illinois early this afternoon. As
elevated moisture and instability surges north into the area, a
leading band of rain is lifting northeast across central and
northeast WI. A more significant area of showers and storms is
moving northeast over east-central Minnesota and northwest
Wisconsin. Some decent radar estimated rainfall has occurred on
the southern edge of this precipitation and just north of the warm
front, with amounts of 1-2" estimated. Some of this heavy rain
could approach central WI by late this afternoon into early this
evening. As the low moves across the region later today,
thunderstorm details and rainfall are the main forecast concerns.

Tonight...Low pressure is expected to track northeast across
central and northeast WI tonight. With this track, parts of
central into the northern Fox Valley will likely see a warm front
move through during the evening, and temps slowly rise for a
several hour period. However, the boundary layer is expected to
remain stable while instability (most unstable capes of 600-900
j/kg) surges in above the inversion. The combination of the
forcing from the low pressure, growing instability, and
precipitable water values upwards of 1.25 inches support the model
depiction of a large area of showers and storms moving across the
area during the evening. Some of the strongest storms could
produce hail and gusty winds. The largest impacts could very well
come via heavy rainfall, as 1 to 1.5 inches of rain (locally up to
2"?) is possible over northern WI. This could lead to some urban
and small stream flooding in the short term, and rises on area
rivers in the long term. The rain will depart from late evening
into the overnight from southwest to northeast behind the low.
Some spotty light rain could linger over far northern WI. Temps
will fall into the mid 30s near the U.P. border to the mid 40s
over the Fox Valley.

Thursday...The low pressure system will rapidly move away from the
region, while upper trough gradually moves overhead from the
northwest. With the arrival of the upper trough, progged soundings
indicate that saturation depth will increase through the day and
up to 600mb over central and north-central WI. This suggests
chances of showers will increase through the day, particularly
over central and north-central WI. Will increase pop chances
slightly. With plenty of clouds and light precip around, temps
will remain cool, and range through the 40s.

.LONG TERM...Thursday Night Through Wednesday
Issued at 246 PM CDT Wed Apr 17 2019

Surface low pressure and upper trough will be exiting the state
Thursday night, with drier air pushing into the area from the
north. The dry air will shut off any lingering evening shower
activity by around midnight. Mainly rain is expected, but thermal
profiles indicate a little snow could mix in over northern WI but
little to no accumulation is expected.

A large area of surface high pressure and upper level ridging
will then spread into the Great Lakes region. This will bring a
break in the unsettled weather, with increasing amounts of
sunshine, and temps climbing to near normal on Friday (mid-upper
50s) and well above normal (60's) on Saturday. The chilly waters
of Lake Michigan will keep temps cooler near the lake. Will need
to keep an eye on RH values Friday and Saturday afternoon as a
very dry airmass (precipitable waters under 0.30" on Friday) will
reside over the area. RH values look to drop into the middle 20s
to middle 30s, lowest across central and north central WI.
Luckily, winds will remain on the light side where the driest air
resides (central/north central WI) with no significant winds to
really mix down (under 15 kts). Plus, recent rains have kept
soils pretty wet, so the overall wildland fire threat should be
minimized.

The chance of showers and maybe a few storms arrives on Sunday as
a cold front swings through the state. Upper support looks to
trail the surface front, plus moisture will be lacking with this
system. Definitely won't be a wash out and most spots will
probably stay dry, but can't rule out a few showers or even a
storm. Models trending toward bringing another low pressure system
across the region early next week, but differences remain, so
hard to pin down any details on how widespread or how much rain we
will get. Temps look to remain near or above normal.
&&

.AVIATION...for 00Z TAF Issuance
Issued at 547 PM CDT Wed Apr 17 2019

Widespread low-end MVFR and IFR conditions are expected this
evening, along with LLWS and widespread showers and scattered
thunderstorms. The primary area of rain will shift east overnight,
but low ceilings are likely to linger into tomorrow.
&&

.HYDROLOGY...
Issued at 246 PM CDT Wed Apr 17 2019

Many area rivers and streams will be on the rise over the next
several days due to melting snow (across the north) and rainfall
today into Thursday. Several rivers in the Wisconsin, Menominee,
and Wolf river basins will be near or above flood stage through
the weekend, with some remaining in flood stage next week. Exactly
how much rain we receive tonight will determine the severity of
the potential flooding, but with another 1-2 inches of rain
forecast to fall into the basins, minor flooding is expected.
Boaters and fishermen should exercise caution, as the high water
levels may create fast flows on some rivers into the weekend.
Rain chances arrive on Sunday, but amounts should be on the low
side. There will be additional rain chances next week at times,
however there remains quite a bit of uncertainly on timing and
amounts. Any additional rain will aggravate the flooding
situation.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

UPDATE.........Skowronski
SHORT TERM.....MPC
LONG TERM......Bersch
AVIATION.......Skowronski
HYDROLOGY......Bersch

Hazardous Weather Outlook
National Weather Service Green Bay WI
245 PM CDT Wed Apr 17 2019

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-181945-
Vilas-Oneida-Forest-Florence-Northern Marinette County-Lincoln-
Langlade-Menominee-Northern Oconto County-Door-Marathon-Shawano-
Wood-Portage-Waupaca-Outagamie-Brown-Kewaunee-Waushara-Winnebago-
Calumet-Manitowoc-Southern Marinette County-
Southern Oconto County-
245 PM CDT Wed Apr 17 2019

This Hazardous Weather Outlook is for north-central and northeast
Wisconsin.

.DAY ONE...Tonight

Showers and thunderstorms may produce over an inch of rain, with
locally higher amounts up to two inches. The rain combined with
remaining snowmelt could produce some flooding of small streams
and urban areas, and continue the slow rise of larger rivers.

Scattered thunderstorms are also expected through the evening. A
few strong storms with hail are possible.

Patchy dense fog will reduce visibilities near Lake Michigan below
one half mile at times through tonight.

.DAYS TWO THROUGH SEVEN...Thursday through Wednesday

The additional rain and runoff from remaining snowmelt will
continue an increased risk of flooding on area rivers. Boaters
and fishermen should also exercise caution, as the high water
levels may lead to fast flows on area rivers into the weekend.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to report hail or rainfall amounts over an
inch to the National Weather Service in Green Bay.

LMZ521-522-541>543-181945-
The Bay of Green Bay south of a line from Cedar River MI to Rock
Island Passage-Lake Michigan from Washington Island to Sheboygan-
245 PM CDT Wed Apr 17 2019

This Hazardous Weather Outlook is for portions of northwest Lake
Michigan and the waters of Green Bay.

.DAY ONE...Tonight

Periods of dense fog will reduce visibilities on Lake Michigan
below one mile at times through tonight.

Scattered thunderstorms this afternoon and evening may pose a hazard
to mariners. Conditions hazardous to small craft are also expected
due to building waves and gusty east to south winds.

.DAYS TWO THROUGH SEVEN...Thursday through Wednesday

Gusty north winds on Thursday afternoon into Thursday night could
create hazardous conditions for small craft.

MPC/Bersch

Special Weather Statement
National Weather Service Green Bay WI
645 PM CDT Wed Apr 17 2019

WIZ018>020-030-031-035-036-180045-
Shawano-Langlade-Wood-Marathon-Portage-Menominee-Lincoln-
645 PM CDT Wed Apr 17 2019

...SHOWERS AND THUNDERSTORMS WITH OCCASIONAL HEAVY RAIN WILL AFFECT
WOOD...PORTAGE... LINCOLN...MARATHON...NORTHWESTERN
MENOMINEE...LANGLADE AND WESTERN SHAWANO COUNTIES EARLY THIS
EVENING...

At 639 PM CDT, a large area of showers with embedded thunderstorms
was over central Wisconsin. The storms moving northeast at 50 mph,
but additional storms were developing to the southwest. Rainfall
totals across central Wisconsin since early afternoon were generally
in the three-quarter to one and one-half inch range. Another inch or
so of rain is likely across much of the area before the
precipitation diminishes later this evening. This could lead to some
ponding of water in low spots on parking lots and roadways, and
minor flooding of low-lying areas.

Locations impacted include...
Wausau, Stevens Point, Wisconsin Rapids, Antigo, Marshfield, Weston,
Merrill, Rib Mountain, Mosinee and Spencer.

Stay indoors when thunderstorms are occurring. Use extra caution if
traveling across the area this evening. Never drive a vehicle into
water of unknown depth.

LAT...LON 4479 9032 4512 9014 4512 9004 4530 9005
      4539 9000 4538 8869 4424 8954 4426 9032
TIME...MOT...LOC 2339Z 236DEG 41KT 4490 8975

Skowronski

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
841 PM CDT WED APR 17 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0841 PM     HEAVY RAIN       PLOVER                  44.45N 89.53W
04/17/2019  M1.34 INCH       PORTAGE            WI   CO-OP OBSERVER

&&

ECKBERG

Special Weather Statement
National Weather Service Green Bay WI
952 PM CDT Wed Apr 17 2019

WIZ011-013-019-021-073-180345-
Southern Marinette County-Langlade-Northern Oconto
County-Forest-Northern Marinette County-
952 PM CDT Wed Apr 17 2019

...SHOWERS AND THUNDERSTORMS WITH OCCASIONAL HEAVY RAIN WILL AFFECT
SOUTHEASTERN FOREST...NORTHERN MARINETTE...NORTHERN OCONTO AND
NORTHEASTERN LANGLADE COUNTIES...

At 947 PM CDT, a large area of showers and thunderstorms was over
northeast Wisconsin. The storms moving northeast at 30 to 40 mph.
Rainfall totals since early afternoon were generally between 1 and
2.5 inches. Another half inch or so of rain is likely across much of
the area late this evening before the precipitation diminishes. This
could lead to some ponding of water in low spots on parking lots and
roadways, and minor flooding of low-lying areas.

Locations impacted include...
Pembine, Goodman, Wausaukee, Carter, McCaslin Mountain Natural Area,
Woodlawn, Laona, Wabeno, Dunbar and Townsend.

Be especially cautious at night when it is harder to recognize the
dangers of flooding. Runoff from the rainfall may cause flooding of
small creeks and streams, country roads, farmland, and other low
lying spots.

LAT...LON 4573 8786 4571 8781 4568 8778 4566 8783
      4560 8777 4556 8779 4556 8783 4554 8780
      4550 8779 4547 8781 4544 8786 4541 8785
      4538 8788 4536 8787 4537 8788 4535 8789
      4518 8892 4557 8883 4575 8787
TIME...MOT...LOC 0247Z 250DEG 24KT 4560 8800

Skowronski