Small Craft Advisory 31, NWS Chicago, IL

163 
WHUS73 KLOT 292119
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
419 PM CDT Mon Mar 29 2021

LMZ740>742-300530-
/O.EXP.KLOT.SC.Y.0030.000000T0000Z-210329T2100Z/
/O.CON.KLOT.GL.W.0010.000000T0000Z-210330T0600Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
419 PM CDT Mon Mar 29 2021

...GALE WARNING REMAINS IN EFFECT UNTIL 1 AM CDT TUESDAY...
...SMALL CRAFT ADVISORY HAS EXPIRED...

* WHAT...South gales to 40 kt expected. Significant waves to 6 
  ft. Occasional waves to 8 ft.

* WHERE...Winthrop Harbor to Wilmette Harbor IL, Wilmette Harbor 
  to Northerly Island IL and Northerly Island to Calumet Harbor 
  IL.

* WHEN...Until 1 AM CDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

* ADDITIONAL DETAILS...The strongest winds will occur within the
  first few miles of the nearshore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

LMZ743>745-300530-
/O.CON.KLOT.SC.Y.0030.000000T0000Z-210329T2300Z/
/O.CON.KLOT.GL.W.0010.210329T2300Z-210330T0600Z/
/O.CON.KLOT.SC.Y.0031.210330T0600Z-210330T1800Z/
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
419 PM CDT Mon Mar 29 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 6 PM CDT THIS
EVENING...
...GALE WARNING REMAINS IN EFFECT UNTIL 1 AM CDT TUESDAY...
...SMALL CRAFT ADVISORY REMAINS IN EFFECT FROM 1 AM TO 1 PM CDT
TUESDAY...

* WHAT...For the Gale Warning, south gales to 40 kt expected. For
  the Small Craft Advisory, south winds around 20 kt with gusts  
  to 30 kt expected. Significant waves to 4 ft.

* WHERE...Calumet Harbor IL to Gary IN, Gary to Burns Harbor IN 
  and Burns Harbor to Michigan City IN.

* WHEN...For the Gale Warning, from 6 PM this evening to 1 AM 
  CDT Tuesday. For the Small Craft Advisory, from 1 AM to 1 PM 
  CDT Tuesday. A Small Craft Advisory remains in effect until 6 
  PM this evening as well.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

* ADDITIONAL DETAILS...The strongest winds will occur within the 
  first few miles of the nearshore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

878 
WHUS73 KLOT 292314
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
614 PM CDT Mon Mar 29 2021

LMZ743>745-300715-
/O.EXP.KLOT.SC.Y.0030.000000T0000Z-210329T2300Z/
/O.CON.KLOT.GL.W.0010.000000T0000Z-210330T0600Z/
/O.CON.KLOT.SC.Y.0031.210330T0600Z-210330T1800Z/
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
614 PM CDT Mon Mar 29 2021

...GALE WARNING REMAINS IN EFFECT UNTIL 1 AM CDT TUESDAY...
...SMALL CRAFT ADVISORY REMAINS IN EFFECT FROM 1 AM TO 1 PM CDT
TUESDAY...

* WHAT...For the Gale Warning, south gales to 40 kt expected. For
  the Small Craft Advisory, south winds around 20 kt with gusts  
  to 30 kt expected. Significant waves to 4 ft.

* WHERE...Gary to Burns Harbor IN, Burns Harbor to Michigan City 
  IN and Calumet Harbor IL to Gary IN.

* WHEN...For the Gale Warning, until 1 AM CDT Tuesday. For the 
  Small Craft Advisory, from 1 AM to 1 PM CDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

* ADDITIONAL DETAILS...The strongest winds will occur within the 
  first few miles of the nearshore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

LMZ740>742-300600-
/O.CON.KLOT.GL.W.0010.000000T0000Z-210330T0600Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
614 PM CDT Mon Mar 29 2021

...GALE WARNING REMAINS IN EFFECT UNTIL 1 AM CDT TUESDAY...

* WHAT...South gales to 40 kt expected. Significant waves to 6 
  ft. Occasional waves to 8 ft.

* WHERE...Northerly Island to Calumet Harbor IL, Winthrop Harbor 
  to Wilmette Harbor IL and Wilmette Harbor to Northerly Island 
  IL.

* WHEN...Until 1 AM CDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

* ADDITIONAL DETAILS...The strongest winds will occur within the
  first few miles of the nearshore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

683 
WHUS73 KLOT 300218
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
918 PM CDT Mon Mar 29 2021

LMZ743>745-301030-
/O.EXT.KLOT.GL.W.0010.000000T0000Z-210330T0800Z/
/O.EXT.KLOT.SC.Y.0031.210330T0800Z-210330T1800Z/
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
918 PM CDT Mon Mar 29 2021

...GALE WARNING NOW IN EFFECT UNTIL 3 AM CDT TUESDAY...
...SMALL CRAFT ADVISORY NOW IN EFFECT FROM 3 AM TO 1 PM CDT
TUESDAY...

* WHAT...For the Gale Warning, south gales to 40 kt expected. For
  the Small Craft Advisory, south winds around 20 kt with gusts 
  up to 30 kt expected. Significant waves to 4 ft.

* WHERE...Gary to Burns Harbor IN, Burns Harbor to Michigan City 
  IN and Calumet Harbor IL to Gary IN.

* WHEN...For the Gale Warning, until 3 AM CDT Tuesday. For the 
  Small Craft Advisory, from 3 AM to 1 PM CDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

* ADDITIONAL DETAILS...The strongest winds will occur within the 
  first few miles of the nearshore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

LMZ740>742-300800-
/O.EXT.KLOT.GL.W.0010.000000T0000Z-210330T0800Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
918 PM CDT Mon Mar 29 2021

...GALE WARNING NOW IN EFFECT UNTIL 3 AM CDT TUESDAY...

* WHAT...South gales to 40 kt expected. Significant waves to 7 ft.
  Occasional waves to 9 ft.

* WHERE...Northerly Island to Calumet Harbor IL, Winthrop Harbor 
  to Wilmette Harbor IL and Wilmette Harbor to Northerly Island 
  IL.

* WHEN...Until 3 AM CDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

* ADDITIONAL DETAILS...The strongest winds will occur within the 
  first few miles of the nearshore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

335 
WHUS73 KLOT 300748
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
248 AM CDT Tue Mar 30 2021

LMZ743>745-301600-
/O.EXP.KLOT.GL.W.0010.000000T0000Z-210330T0800Z/
/O.EXT.KLOT.SC.Y.0031.210330T0800Z-210330T2100Z/
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
248 AM CDT Tue Mar 30 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 4 PM CDT THIS
AFTERNOON...
...GALE WARNING WILL EXPIRE AT 3 AM CDT EARLY THIS MORNING...

* WHAT...South to southwest winds around 20 kt with gusts up to 
  30 kt expected. Significant waves to 4 ft.

* WHERE...Gary to Burns Harbor IN, Burns Harbor to Michigan City 
  IN and Calumet Harbor IL to Gary IN.

* WHEN...Until 4 PM CDT this afternoon.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LMZ740>742-301600-
/O.EXP.KLOT.GL.W.0010.000000T0000Z-210330T0800Z/
/O.EXB.KLOT.SC.Y.0031.210330T0800Z-210330T2100Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
248 AM CDT Tue Mar 30 2021

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 4 PM CDT THIS AFTERNOON...
...GALE WARNING WILL EXPIRE AT 3 AM CDT EARLY THIS MORNING...

* WHAT...South to southwest winds around 20 kt with gusts up to 30
  kt expected. Significant waves to 5 ft.

* WHERE...Winthrop Harbor to Wilmette Harbor IL, Wilmette Harbor 
  to Northerly Island IL and Northerly Island to Calumet Harbor 
  IL.

* WHEN...Until 4 PM CDT this afternoon.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Ogorek

765 
WHUS73 KLOT 301455
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
955 AM CDT Tue Mar 30 2021

LMZ740>745-302300-
/O.EXT.KLOT.SC.Y.0031.000000T0000Z-210331T0000Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
955 AM CDT Tue Mar 30 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 7 PM CDT THIS
EVENING...

* WHAT...Southwest winds to 30 kt expected. A few gale force gusts
  to 35 kt through early afternoon. Significant waves to 5 ft.

* WHERE...Illinois and Indiana nearshore waters of Lake Michigan.
 
* WHEN...Until 7 PM CDT this evening.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

599 
WHUS73 KLOT 302029
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
329 PM CDT Tue Mar 30 2021

LMZ740>745-310300-
/O.EXT.KLOT.SC.Y.0031.000000T0000Z-210331T0300Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
329 PM CDT Tue Mar 30 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 10 PM CDT THIS
EVENING...

* WHAT...West winds to 25 kt. Significant waves to 4 ft.

* WHERE...Illinois and Indiana nearshore waters of Lake Michigan.

* WHEN...Until 10 PM CDT this evening.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

485 
WHUS73 KLOT 310233
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
933 PM CDT Tue Mar 30 2021

LMZ740>745-310900-
/O.EXT.KLOT.SC.Y.0031.000000T0000Z-210331T0900Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
933 PM CDT Tue Mar 30 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 4 AM CDT WEDNESDAY...

* WHAT...Northwest winds to 25 kt. Significant waves to 4 ft.

* WHERE...Illinois and Indiana nearshore waters of Lake Michigan.

* WHEN...Until 4 AM CDT Wednesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Carlaw

701 
WHUS73 KLOT 310831
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
331 AM CDT Wed Mar 31 2021

LMZ744-745-311645-
/O.CON.KLOT.SC.Y.0031.000000T0000Z-210331T0900Z/
/O.NEW.KLOT.SC.Y.0032.210401T0000Z-210402T0500Z/
Gary to Burns Harbor IN-Burns Harbor to Michigan City IN-
331 AM CDT Wed Mar 31 2021

...SMALL CRAFT ADVISORY IN EFFECT FROM 7 PM THIS EVENING TO
MIDNIGHT CDT THURSDAY NIGHT...

* WHAT...North winds and waves 6 to 9 ft expected.

* WHERE...Gary to Burns Harbor IN and Burns Harbor to Michigan 
  City IN.

* WHEN...From 7 PM this evening to midnight CDT Thursday night.

* IMPACTS...Conditions will be hazardous to small craft.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LMZ740>743-311645-
/O.EXT.KLOT.SC.Y.0031.000000T0000Z-210331T1500Z/
/O.NEW.KLOT.SC.Y.0032.210401T0300Z-210402T0300Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-
331 AM CDT Wed Mar 31 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 10 AM CDT THIS
MORNING...
...SMALL CRAFT ADVISORY IN EFFECT FROM 10 PM THIS EVENING TO
10 PM CDT THURSDAY...

* WHAT...For the first Small Craft Advisory, northwest winds
  gusting to 25 kt. For the second Small Craft Advisory, north 
  winds to 25 kt and waves 5 to 8 ft expected.

* WHERE...Winthrop Harbor to Wilmette Harbor IL, Wilmette Harbor 
  to Northerly Island IL, Northerly Island to Calumet Harbor IL 
  and Calumet Harbor IL to Gary IN.

* WHEN...For the first Small Craft Advisory, until 10 AM CDT this
  morning. For the second Small Craft Advisory, from 10 PM this 
  evening to 10 PM CDT Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

761 
WHUS73 KLOT 311447
MWWLOT

URGENT - MARINE WEATHER MESSAGE
National Weather Service Chicago IL
947 AM CDT Wed Mar 31 2021

LMZ740>743-312300-
/O.EXP.KLOT.SC.Y.0031.000000T0000Z-210331T1500Z/
/O.CON.KLOT.SC.Y.0032.210401T0300Z-210402T0300Z/
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-
947 AM CDT Wed Mar 31 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT FROM 10 PM THIS EVENING
TO 10 PM CDT THURSDAY...

* WHAT...North winds to 25 kt and waves up to 5 to 8 ft 
  occasionally to 10 ft expected.

* WHERE...Winthrop Harbor to Wilmette Harbor IL, Wilmette Harbor 
  to Northerly Island IL, Northerly Island to Calumet Harbor IL 
  and Calumet Harbor IL to Gary IN.

* WHEN...From 10 PM this evening to 10 PM CDT Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LMZ744-745-312300-
/O.EXT.KLOT.SC.Y.0032.210331T1800Z-210402T0500Z/
Gary to Burns Harbor IN-Burns Harbor to Michigan City IN-
947 AM CDT Wed Mar 31 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT FROM 1 PM THIS AFTERNOON TO
MIDNIGHT CDT THURSDAY NIGHT...

* WHAT...North winds to 25 to 30 kt and waves up to 6 to 9 ft
  occasionally to 12 ft expected.

* WHERE...Gary to Burns Harbor IN and Burns Harbor to Michigan 
  City IN.

* WHEN...From 1 PM this afternoon to midnight CDT Thursday night.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
251 PM CDT Mon Mar 29 2021

.UPDATE...
1113 AM CDT

No significant changes to the forecast or forecast message today
with the inherited grids in great shape. The Red Flag Warning
continues for our northwestern CWA where the combination of
stronger wind gusts will more closely overlap minimum afternoon
RHs as low as about 25% to promote a critical fire danger.
Elsewhere, we'll be on the edge, but latest indications suggest RH
values remaining just a bit above strict criteria, with the
message handled appropriately by the current Special Weather
Statement.

The main uncertainty today regarding sensible fire weather impacts
continues to be on dewpoint trends, with morning guidance pushing
upper 30 degree dewpoints into the region through the mid and late
afternoon hours. Surface observations do indeed show dewpoints
inching upwards--perhaps as a result of mixing some of the
slightly higher mixing-ratio air observed on the ILX/DVN soundings
just off the surface. Current thinking is that our current gridded
forecast strikes a good balance between walking the dewpoints up
slowly with time, but not so high that we bust the RH forecast by
a wide margin--not a good thing on a day where winds will be
routinely gusting to 30-40 mph with time into the afternoon.

The other aspect we'll be taking a look at with the afternoon
package is the need for a targeted Wind Advisory closer to the
urbanized corridors across northeast Illinois/northwest Indiana
this evening as an impressive low-level jet begins to strengthen.
With 40-50 kt winds only 1000-1500 feet off the deck, it won't
take much of a lingering near-surface mixed layer to transport
gusts to 45-50 mph to the surface. In the meantime, updated
products have been transmitted.

Carlaw

&&

.SHORT TERM...
251 PM CDT

Through Tuesday night...

Short term discussion will be issued shortly.

&&

.LONG TERM...
251 PM CDT

Wednesday through Monday...

Overall, after Tuesday nights precipitation most of the area
looks to remain precipitation free for Wednesday and Thursday. The
main exception to this, will be parts of northwestern Indiana
near Lake Michigan late Wednesday night into Thursday morning,
where lake effect precipitation will be increasingly possible.
With the heart of the cold airmass moving over southern Lake
Michigan during this period, the thermodynamic setup over the lake
looks rather impressive (especially for the first day of April)
to support a period of lake effect snow, with ELs approaching
10kft and lake induced CAPE of 300-500 j/kg.

While this is still a few days away, this will bear watching as
the potential exists for some accumulating snow from this lake
effect into Thursday. The best chances for this look to remain
over my northwestern IN counties, especially Porter and points
east, though Lake County Indiana could get clipped for a time as
well depending on how the lake induced convergence axis sets up.
It appears the main lacking element in this setup will be
moisture, which will be rather shallow. PoPs were kept in the mid
chance range for now. Temperatures will be much cooler Wednesday
and Thursday, only in the low to perhaps mid 40s, and some
locations near the lake possibly not getting out of the upper 30s.
The mild weather of late has allowed for a relatively early start
to green-up, so keep in mind the lows in the 20s area-wide on both
Wednesday and Thursday nights if you need to protect any plants.

A surface ridge axis will shift over the area Thursday night.
After this passes to our east the winds will turn southerly again
by Friday. This will allow temperatures to quickly moderate back
into the 60s to near 70 for Saturday, and lower 70s for Sunday,
with mid 70s possible in spots. Blocked moisture trajectories into
the weekend and gusty southwesterly winds amidst the warmth could
set the stage for an elevated fire weather risk on Saturday. Main
item of uncertainty for Sunday is the possibility of a backdoor
cold front Saturday evening that could flip winds onshore and keep
the Illinois shore a good deal cooler until late Easter Sunday. We
finally get into some moisture return into the start of next work
week, which may set the stage for a return of shower and even
thunderstorm chances sometime Monday or Monday night. The warm
temps (highs in low-mid 70s) will continue on Monday.

KJB/Castro

&&

.FIRE WEATHER...
445 AM CDT

Elevated to critical fire weather conditions are expected to develop
today, especially northwest of a line from Mendota to Woodstock.
As a strong low-level pressure gradient develops across the Upper
Mississippi River Valley Monday morning and afternoon, southerly
winds will increase with 20 ft winds of 20-25 mph and gusts of 35
to 45 mph expected by mid-afternoon. Meanwhile, surface temperatures
will rise to the low-mid 60s.

Forecast model guidance suggests surface dew points will rise some
10 to 15 degrees into the upper 30s/low 40s by Monday afternoon,
which seems dubiously too high considering 1). Forecast low-level
moisture profiles featuring decreasing moisture with height; 2).
Ideal mixing and hence dry air entrainment; 3). Lack of "green"
vegetation and any meaningful evapotranspiration; and 4). Dearth
of low-level moisture upstream across the Southern Plains. As
such, we believe dew points tomorrow may struggle to climb as
easily as forecast models would suggest, hence impacting minimum
afternoon relative humidity values. The outgoing forecast features
minimum afternoon relative humidity in the 25 to 30 percent range
across most of the area, which may still end up too high.
Additionally, WFAS forecast 10-hr fuel moisture (which is below
10% across north-central Illinois for Monday) has been running
too high the past few days, and locations generally northwest of
I-55 have seen less than 0.25" of rain since 3/23/2021. As such,
fine fuels such as grasses and shrubs across north-central
Illinois may be dry enough to easily burn.

Taken altogether, elevated to critical fire weather danger will
develop Monday afternoon, highest northwest of a line from Mendota
to Woodstock. A Red Flag Warning was issued for Boone, Lee, Ogle,
and Winnebago counties, which is where forecasted 20 ft winds,
minimum relative humidities, and 10-hr fuel moistures all breach
or get very close to Red Flag Warning criteria Monday afternoon
into early Monday evening. Elsewhere, a Special Weather Statement
was issued to highlight the elevated fire weather danger that did
not quite meet Red Flag Warning criteria. Nevertheless, any
planned outdoor burning should be postponed today.

Borchardt/Ogorek

&&

.AVIATION...
For the 18Z TAFs...
100 PM CDT

Main concern:
* Strong and gusty southerly winds becoming southwesterly ahead of
  a cold front on Tuesday
* A period of 40-45 kt gusts appearing increasingly likely at ORD
  and MDW this evening from a 190-200 deg direction
* LLWS tonight into Tuesday morning
* Chance for patchy MVFR CIGs on Tuesday ahead of a cold front

Very strong low pressure tracking across the southern Canadian
Prairies and expansive high pressure to the east are yielding a
tight pressure gradient and strong and gusty southerly winds from
a 160-190 deg direction. Highest winds overall have been over
northwest and north central Illinois, but already within the past
hour have gusted as high as 34 kt at MDW. RFD area should be in
the 32-39 kt range for prevailing gusts this afternoon, with
initially 25-35 kt range over the Chicago area. Forecast soundings
indicate strengthening low level jet later this afternoon will
result in even stronger winds, with these continuing through the
evening, peaking in magnitude over the urban heat island of the
Chicago metro.

Based off a recent fairly similar setup on March 10th- 11th,
think that highest gusts over the Chicago metro should be this
evening, when at least temporary 40-45 kt gusts appear likely.
Potential exists for brief 45+ kt gusts given very low altitude of
45+ kt flow in forecast soundings. Have adjusted up wind speeds
and gusts in the TAF a bit. RFD should see its highest gusts in
the mid afternoon through early evening, and then ease a bit as
mixing depth decreases. Uncertainty is also a bit higher for GYY
this evening. 50+ kt southwesterly flow at and above 2kft AGL will
also support LLWS when gust magnitude eases tonight. Out ahead of
the cold front tomorrow, quite possible gusts will jump back into
the 30-35 kt range as direction shifts to a more friendly
southwesterly direction. There's some potential for brief higher
MVFR CIGs until patchy lower clouds scatter with the cold front
and direction shifts to west and west-northwest.

Castro

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...Red Flag Warning...ILZ003-ILZ004-ILZ008-ILZ010 until 8 PM Monday.

     Wind Advisory...ILZ003-ILZ004-ILZ008-ILZ010 until 8 PM Monday.

IN...None.
LM...Gale Warning...IL nearshore waters until 1 AM Tuesday.

     Small Craft Advisory...IL nearshore waters until 4 PM Monday.

     Small Craft Advisory...IN nearshore waters until 1 PM Tuesday.

&&

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Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
307 AM CDT Mon Mar 29 2021

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-300815-
Winnebago-Boone-McHenry-Lake IL-Ogle-Lee-De Kalb-Kane-DuPage-
La Salle-Kendall-Grundy-Kankakee-Livingston-Iroquois-Ford-
Northern Cook-Central Cook-Southern Cook-Northern Will-
Southern Will-Eastern Will-Lake IN-Porter-Newton-Jasper-Benton-
307 AM CDT Mon Mar 29 2021 /407 AM EDT Mon Mar 29 2021/

This Hazardous Weather Outlook is for portions of North Central
Illinois...Northeast Illinois and Northwest Indiana.

.DAY ONE...Today and Tonight.

Weather hazards expected...

  Significant Fire Weather Risk.
  Elevated Non thunderstorm wind Risk.

DISCUSSION...

Windy and dry conditions are expected again today, and this will
result in a significant fire danger across parts of the area this
afternoon. The worst conditions are expected west of the Chicago
metro area, across parts of northwestern and far north central
Illinois.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday through Thursday...
  Limited Non Thunderstorm Wind Risk.
Friday...
  Elevated Fire Weather Risk.

.SPOTTER INFORMATION STATEMENT...

  Spotter activation will not be necessary through tonight.

LMZ740>745-300815-
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
307 AM CDT Mon Mar 29 2021

This Hazardous Weather Outlook is for portions of the Illinois
nearshore waters of Lake Michigan and the Indiana nearshore
waters of Lake Michigan.

.DAY ONE...Today and Tonight.

Weather hazards expected...

 Gale force winds and very hazardous waves are expected.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday through Thursday...
  Hazardous conditions for small craft are likely.

KJB

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SPECIAL WEATHER STATEMENT
National Weather Service Chicago/Romeoville IL
1058 AM CDT Mon Mar 29 2021

ILZ005-006-011>013-019>021-023-032-033-039-103>108-INZ001-002-010-
011-019-300100-
McHenry-Lake IL-De Kalb-Kane-DuPage-La Salle-Kendall-Grundy-
Kankakee-Livingston-Iroquois-Ford-Northern Cook-Central Cook-
Southern Cook-Northern Will-Southern Will-Eastern Will-Lake IN-
Porter-Newton-Jasper-Benton-
Including the cities of Crystal Lake, Algonquin, McHenry,
Woodstock, Waukegan, Buffalo Grove, Mundelein, Gurnee, DeKalb,
Sycamore, Aurora, Elgin, Naperville, Wheaton, Downers Grove,
Lombard, Carol Stream, Ottawa, Streator, La Salle, Mendota,
Marseilles, Oswego, Yorkville, Plano, Morris, Coal City, Minooka,
Kankakee, Bourbonnais, Bradley, Pontiac, Dwight, Fairbury,
Watseka, Gilman, Paxton, Gibson City, Evanston, Des Plaines,
Schaumburg, Palatine, Northbrook, Chicago, Cicero, Oak Lawn,
Oak Park, La Grange, Calumet City, Oak Forest, Lemont,
Orland Park, Park Forest, Joliet, Bolingbrook, Plainfield,
Mokena, Channahon, Manhattan, Wilmington, Crete, Peotone,
Beecher, Gary, Hammond, Merrillville, Portage, Valparaiso,
Chesterton, Roselawn, Kentland, Morocco, Rensselaer, DeMotte,
Fowler, and Oxford
1058 AM CDT Mon Mar 29 2021 /1158 AM EDT Mon Mar 29 2021/

...Elevated Brushfire Danger This Afternoon and Early Evening...

The combination of low relative humidity, gusty south winds, mild
temperatures, and dried-out grasses and shrubs will lead to an
elevated threat for quickly-spreading, uncontrolled brushfires
this afternoon and early evening. Outdoor burning today is
strongly discouraged.

BKL