939 

WHUS51 KBOX 171924
SMWBOX
ANZ235>237-256-172030-
/O.NEW.KBOX.MA.W.0002.260417T1924Z-260417T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Boston/Norton MA
324 PM EDT Fri Apr 17 2026

The National Weather Service in Boston/Norton has issued a

* Special Marine Warning for...
  Block Island Sound...
  Coastal Waters from Montauk NY to Marthas Vineyard extending out to
  20 NM South of Block Island...
  Narragansett Bay...
  Rhode Island Sound...

* Until 430 PM EDT.

* At 324 PM EDT, severe thunderstorms were located along a line
  extending from 6 nm northwest of South Kingstown to near
  Stonington, moving southeast at 30 knots.

  HAZARD...Wind gusts 34 knots or greater and hail up to penny size.

  SOURCE...Radar.

  IMPACT...Small craft could be damaged in briefly higher winds and
           suddenly higher waves. Large hail could result in
           structural damage.

* Locations impacted include...
  Watch Hill, Charlestown Breachway, Dutch Harbor Light, Block Island
  Sound, The Coastal Waters West Of Block Island, Point Judith Light,
  Castle Hill Light, Narragansett Bay, Rhode Island Sound, and The
  Coastal Waters Between Block Island And Marthas Vineyard.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

Frequent lightning is occurring with these storms. If caught on the
open water stay below deck if possible, keep away from ungrounded
metal objects.

&&

LAT...LON 4132 7187 4132 7185 4135 7182 4140 7151
      4151 7145 4153 7146 4115 7079 4083 7166
      4099 7180 4114 7187 4131 7188
TIME...MOT...LOC 1924Z 312DEG 30KT 4154 7162 4143 7189

HAIL...>.75IN
WIND...>34KTS

$$

Loconto






339 

WHUS53 KDLH 171929
SMWDLH
LSZ143>145-162-172015-
/O.NEW.KDLH.MA.W.0001.260417T1929Z-260417T2015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Duluth MN
229 PM CDT Fri Apr 17 2026

The National Weather Service in Duluth MN has issued a

* Special Marine Warning for...
  Duluth MN to Port Wing WI...
  Lake Superior west of a line from Saxon Harbor WI to Grand Portage
  MN beyond 5NM...
  Silver Bay Harbor to Two Harbors MN...
  Two Harbors to Duluth MN...

* Until 315 PM CDT.

* At 229 PM CDT, a severe thunderstorm was located near Superior
  Harbor, or 9 nm south of Duluth Lift Bridge Channel, moving
  northeast at 40 knots.

  HAZARD...Wind gusts 34 knots or greater and large hail.

  SOURCE...Radar.

  IMPACT...Small craft could be damaged in briefly higher winds and
           suddenly higher waves. Large hail could result in
           structural damage.

* The severe thunderstorm will be near...
  Superior Harbor, Barkers Island, Duluth Harbor, and Superior Entry
  around 235 PM CDT.
  McQuade Harbor around 245 PM CDT.
  French River and Stoney Point around 250 PM CDT.
  Knife River Marina around 255 PM CDT.
  Larsmont around 300 PM CDT.
  Two Harbors Protected Access Agate Bay around 305 PM CDT.

Other locations impacted by the severe thunderstorm include Superior
Entry.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

Frequent lightning is occurring with this storm. If caught on the
open water stay below deck if possible, keep away from ungrounded
metal objects.

&&

LAT...LON 4678 9214 4711 9156 4698 9132 4671 9167
      4666 9200 4666 9203 4671 9210 4666 9211
      4665 9216 4662 9221 4663 9224
TIME...MOT...LOC 1929Z 208DEG 41KT 4662 9204

HAIL...>.75IN
WIND...>34KTS

$$

PA