Alert archive / Indiana / Special Marine Warnings in 2021

Special Marine Warning 21, NWS Northern Indiana

August 24, 2021

NWS Northern Indiana issued this special marine warning at Aug 24, 2021, 9:23 PM EDT. It was in force for 67 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 24, 2021, 9:23 PM EDT (01:23 UTC)
Expired
Aug 24, 2021, 10:30 PM EDT
In force
67 min
Issued by
NWS Northern Indiana
Area
Storm-based polygon
Hail
0.0 in
Wind
34.0 mph

The radar

The Northern Indiana radar (KIWX), 107 km from the middle of the area, began a volume at 01:27 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.4 hours before the alert went out and 247 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2021-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2737 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2021-08-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
2737 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
1274 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
120 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.3

Open this sounding in Storm Lab

The text

As transmitted.

023 
WHUS53 KIWX 250123
SMWIWX
LMZ043-046-080-250230-
/O.NEW.KIWX.MA.W.0021.210825T0123Z-210825T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Northern Indiana
923 PM EDT Tue Aug 24 2021

The National Weather Service in Northern Indiana has issued a

* Special Marine Warning for...
  Lake Michigan Michigan City IN to St. Joseph MI 5 NM offshore to
  mid-line of lake....
  Michigan City IN to New Buffalo MI...
  New Buffalo MI to St Joseph MI...
  Nearshore and open waters from Michigan City IN to St. Joseph MI...

* Until 1030 PM EDT.

* At 922 PM EDT, a strong thunderstorm was located near New Buffalo,
  or 7 nm north of Michigan City, moving northeast at 20 knots.

  HAZARD...Wind gusts 34 knots or greater.

  SOURCE...Radar.

  IMPACT...Small craft could be damaged in briefly higher winds and 
           suddenly higher waves.

* Locations impacted include...
  New Buffalo, St. Joseph and Michigan City. 

LAT...LON 4172 8691 4179 8696 4179 8697 4212 8696
      4213 8657 4211 8649 4206 8650 4190 8657
      4178 8673 4172 8690
TIME...MOT...LOC 0122Z 237DEG 21KT 4183 8681 

HAIL...0.00IN
WIND...>34KTS

$$

RTC

The office that day

Everything else NWS Northern Indiana issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 24, 8:29 PM EDTSevere Thunderstorm WarningIWXLaPorte, Saint Joseph46 min
Aug 24, 8:33 PM EDTSpecial Marine WarningIWX57 min
Aug 24, 9:02 PM EDTSevere Thunderstorm WarningIWXElkhart, Saint Joseph43 min
Aug 24, 9:57 PM EDTSpecial Weather StatementIWXLaGrange33 min
Aug 24, 10:20 PM EDTSpecial Weather StatementIWXLaGrange25 min
Aug 24, 10:24 PM EDTSpecial Weather StatementIWXLaPorte, Starke66 min
Aug 25, 6:26 PM EDTSpecial Weather StatementIWXWhite34 min
Aug 24, 8:14 PM EDTAreal Flood AdvisoryIWXBerrien, Cass3 hr
Aug 24, 8:30 PM EDTSevere Thunderstorm WarningIWXCass30 min
Aug 24, 9:40 PM EDTSpecial Weather StatementIWXBranch35 min

Nearby

Special Marine Warnings in Indiana, 2021Every special marine warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.