The threat for severe weather in the area covered by severe thunderstorm watch number 363 (the one that covers northern Indiana) continues, according to a mesoscale discussion that the National Weather Service Storm Prediction Center issued at 10:20 p.m. EDT. The discussion indicates that a large hail threat might be developing over Illinois as storms regenerate there and then form a train toward the east, creating a heavy rain threat. The discussion indicates that a new watch might be needed over portions of Illinois and Indiana, as watch number 363 is set to expire at 11 p.m. EDT.

URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 363
   NWS STORM PREDICTION CENTER NORMAN OK
   305 PM CDT TUE JUN 25 2013

   THE NWS STORM PREDICTION CENTER HAS ISSUED A

   * SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
     NORTH CENTRAL ILLINOIS
     NORTHERN INDIANA
     NORTHWEST OHIO

   * EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 305 PM UNTIL
     1000 PM CDT.

   * PRIMARY THREATS INCLUDE...
     NUMEROUS DAMAGING WIND GUSTS TO 70 MPH LIKELY
     SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO 2
       INCHES IN DIAMETER POSSIBLE

   THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65
   STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES WEST OF
   PEORIA ILLINOIS TO 25 MILES SOUTHEAST OF FORT WAYNE INDIANA.  FOR
   A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
   OUTLINE UPDATE (WOUS64 KWNS WOU3).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
   FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
   AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
   THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
   AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
   DO PRODUCE TORNADOES.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 361...WW 362...

   DISCUSSION...STORM DEVELOPMENT IS NOW UNDERWAY ACROSS CENTRAL
   ILLINOIS... PERHAPS AIDED BY FORCING ASSOCIATED WITH A SHORT WAVE
   IMPULSE MIGRATING EAST OF THE MIDDLE MISSISSIPPI VALLEY.  IN THE
   PRESENCE OF THERMODYNAMIC PROFILES CHARACTERIZED BY FAIRLY STEEP
   MID-LEVEL LAPSE RATES AND LARGE CAPE...DEEP LAYER WESTERLY FLOW AND
   VERTICAL SHEAR IS SUFFICIENT TO SUPPORT THE UPSCALE GROWTH FROM
   SUPERCELLS TO AN INCREASINGLY ORGANIZED...EASTWARD ADVANCING
   MESOSCALE CONVECTIVE SYSTEM CAPABLE OF PRODUCING DAMAGING WIND
   GUSTS.

SEVERE THUNDERSTORM WATCH 363 IS IN EFFECT UNTIL 1000 PM CDT
   FOR THE FOLLOWING LOCATIONS

   ILC017-019-021-039-041-045-053-057-063-075-091-093-095-099-105-
   107-113-115-123-125-129-137-139-143-147-167-175-179-183-197-203-
   260300-
   /O.NEW.KWNS.SV.A.0363.130625T2005Z-130626T0300Z/

   IL 
   .    ILLINOIS COUNTIES INCLUDED ARE

   CASS                 CHAMPAIGN           CHRISTIAN           
   DE WITT              DOUGLAS             EDGAR               
   FORD                 FULTON              GRUNDY              
   IROQUOIS             KANKAKEE            KENDALL             
   KNOX                 LA SALLE            LIVINGSTON          
   LOGAN                MACON               MARSHALL            
   MASON                MCLEAN              MENARD              
   MORGAN               MOULTRIE            PEORIA              
   PIATT                SANGAMON            STARK               
   TAZEWELL             VERMILION           WILL                
   WOODFORD             


   INC001-003-007-009-011-015-017-023-033-035-039-045-049-053-057-
   059-063-065-067-069-073-075-085-087-089-091-095-097-099-103-107-
   111-113-121-127-131-133-135-141-149-151-157-159-165-169-171-179-
   181-183-260300-
   /O.NEW.KWNS.SV.A.0363.130625T2005Z-130626T0300Z/

   IN 
   .    INDIANA COUNTIES INCLUDED ARE

   ADAMS                ALLEN               BENTON              
   BLACKFORD            BOONE               CARROLL             
   CASS                 CLINTON             DELAWARE            
   DE KALB              ELKHART             FOUNTAIN            
   FULTON               GRANT               HAMILTON            
   HANCOCK              HENDRICKS           HENRY               
   HOWARD               HUNTINGTON          JASPER              
   JAY                  KOSCIUSKO           LAGRANGE            
   LAKE                 LA PORTE            MADISON             
   MARION               MARSHALL            MIAMI               
   MONTGOMERY           NEWTON              NOBLE               
   PARKE                PORTER              PULASKI             
   PUTNAM               RANDOLPH            ST. JOSEPH          
   STARKE               STEUBEN             TIPPECANOE          
   TIPTON               VERMILLION          WABASH              
   WARREN               WELLS               WHITE               
   WHITLEY              


   OHC003-039-051-069-125-137-161-171-260300-
   /O.NEW.KWNS.SV.A.0363.130625T2005Z-130626T0300Z/

   OH 
   .    OHIO COUNTIES INCLUDED ARE

   ALLEN                DEFIANCE            FULTON              
   HENRY                PAULDING            PUTNAM              
   VAN WERT             WILLIAMS    

URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 362
   NWS STORM PREDICTION CENTER NORMAN OK
   340 PM EDT TUE JUN 25 2013

   THE NWS STORM PREDICTION CENTER HAS ISSUED A

   * SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
     WESTERN MARYLAND
     NORTHERN AND CENTRAL OHIO
     WESTERN PENNSYLVANIA
     NORTHERN WEST VIRGINIA
     LAKE ERIE

   * EFFECTIVE THIS TUESDAY AFTERNOON FROM 340 PM UNTIL MIDNIGHT
     EDT.

   * PRIMARY THREATS INCLUDE...
     SEVERAL DAMAGING WIND GUSTS TO 70 MPH LIKELY
     SEVERAL LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE

   THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 70
   STATUTE MILES NORTH AND SOUTH OF A LINE FROM 30 MILES EAST OF
   LATROBE PENNSYLVANIA TO 65 MILES NORTH NORTHWEST OF DAYTON OHIO. 
   FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
   OUTLINE UPDATE (WOUS64 KWNS WOU2).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
   FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
   AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
   THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
   AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
   DO PRODUCE TORNADOES.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 361...

   DISCUSSION...STORM DEVELOPMENT IS NOW WELL UNDERWAY IN THE PRESENCE
   OF MODERATE BOUNDARY LAYER INSTABILITY.  CONSOLIDATING COLD POOLS
   MAY CONTRIBUTE TO FURTHER UPSCALE CONVECTIVE GROWTH...AND THE
   EVOLUTION OF ONE OR TWO SMALL STORM CLUSTERS ACCOMPANIED BY THE RISK
   FOR DAMAGING WIND GUSTS.  EAST SOUTHEASTWARD MOTION WILL BE ENHANCED
   BY A BELT OF 20-30 KT WESTERLY LOWER/MID TROPOSPHERIC FLOW.

   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
   MOTION VECTOR 27030.


   ...KERR

SEVERE THUNDERSTORM WATCH 362 IS IN EFFECT UNTIL 1200 AM EDT
   FOR THE FOLLOWING LOCATIONS

   OH 
   .    OHIO COUNTIES INCLUDED ARE

   ALLEN                ASHLAND             ASHTABULA           
   ATHENS               AUGLAIZE            BELMONT             
   CARROLL              CHAMPAIGN           CLARK               
   COLUMBIANA           COSHOCTON           CRAWFORD            
   CUYAHOGA             DARKE               DELAWARE            
   ERIE                 FAIRFIELD           FAYETTE             
   FRANKLIN             GEAUGA              GREENE              
   GUERNSEY             HANCOCK             HARDIN              
   HARRISON             HOCKING             HOLMES              
   HURON                JEFFERSON           KNOX                
   LAKE                 LICKING             LOGAN               
   LORAIN               LUCAS               MADISON             
   MAHONING             MARION              MEDINA              
   MERCER               MIAMI               MONROE              
   MONTGOMERY           MORGAN              MORROW              
   MUSKINGUM            NOBLE               OTTAWA              
   PERRY                PICKAWAY            PORTAGE             
   PREBLE               RICHLAND            SANDUSKY            
   SENECA               SHELBY              STARK               
   SUMMIT               TRUMBULL            TUSCARAWAS          
   UNION                WASHINGTON          WAYNE               
   WOOD                 WYANDOT             

 

See an update to this post.

The National Weather Service Storm Prediction Center might soon issue a watch for parts of northern Ohio, possibly including part of IMO SKYWARN quadrant two (see map above). The SPC issued a mesoscale discussion at 3:04 p.m. EDT that indicates the potential is increasing across identified area for damaging gusts and isolated large hail as storms continue to develop and move generally eastward into a destabilizing air mass.

Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point. (More Info)

The risk of severe weather in Indiana and surrounded areas has increased and expanded, according to the Day 1 Convective Outlook that the National Weather Service (NWS) Storm Prediction Center (SPC) issued at 8:52 a.m. EDT. The SPC increased the slight risk area from the northern half of Indiana to the northern two thirds of the state. It also broadly increased the slight risk area to the east.

In addition, and perhaps more significant to readers of this blog, the probabilities of severe wind and hail in northern Indiana doubled from the previous outlook. Throughout the area covered by the Northern Indiana NWS office (see map at right), the probability of damaging thunderstorm winds or wind gusts of 50 knots (58 mph) or higher within 25 miles of a point is now 30 percent. In the same area, the SPC also forecasts a 30 percent probability of one inch diameter hail or larger within 25 miles of a point.

This morning, Warning Coordination Meteorologist Michael Lewis of the northern Indiana NWS office provided the following information via email to SKYWARN storm spotters:

Today:

Threat: Severe Winds > 58 MPH with Isolated damaging winds > 70 mph and torrential rainfall.

Timing: Isolated storms from mid-day through early afternoon. Redevelopment into more linear during the late afternoon into the evening. Location: Early this morning along and north or US-30. Development along and south of US-24 around mid-day. Development west of IN-9 later this afternoon with rapid eastward expansion.

Wednesday:

Threat: Straight Line Winds. Widespread damaging winds possible > 70 mph, hail > 1″ diameter, and torrential rainfall.

Timing: Squall line development early afternoon, rapidly building and accelerating across Indiana through early evening.

Location: Early this morning along and north or US-30. Development along and south of US-24 around mid-day. Development west of IN-9 later this afternoon with rapid eastward expansion.

Northern Indiana (NWS office) will be monitoring:

• Emergency Managers and Media Partners
• Social Media – (Facebook / Twitter)
• Amateur Radio
• e-mail (w-iwx.webmaster@noaa.gov)

See an update to this post.

The northern half of Indiana (see the map at top left) as well as some surrounding areas remains at slight risk of severe weather between 8 a.m. today and 8 a.m. tomorrow, according to the Day 1 Convective Outlook that the National Weather Service (NWS) Storm Prediction Center issued at 1:59 a.m. EDT. All 37 counties served by the northern Indiana NWS office are included. The main threats are damaging straight-line winds and hail but there’s a small risk of tornadoes as well.

Between 8 a.m. tomorrow and 8 a.m. Thursday, the entire state of Indiana plus a large surrounding area (see map at lower left) remains under a slight risk.

Unfortunately for Fort Wayne residents, this slight risk is occurring while the Fort Wayne NOAA Weather Radio transmitter is crippled. Due to a part failure the transmitter is running at reduced power, until the ordered part comes in. That means your weather radio might not be picking up the signal, which also means it won’t alert you of watches and warnings.

I suggest you check your weather radio now to see if you can hear the continuous broadcast. If you can, you’lre probably OK. If not, plan to monitor a local TV or radio station so you’ll know if a watch or warning comes out.

The National Weather Service (NWS) has issued severe thunderstorm watch number 358 for a large part of northern Indiana until midnight EDT. The watch includes all 37 Indiana, Michigan and Ohio counties covered by the Northern Indiana NWS office.

The NWS Storm Prediction Center indicated in a mesoscale discussion that a severe thunderstorm system is moving across northeastern Illinois and severe winds are expected from it as it continues east across southern Lake Michigan, southwestern lower Michigan and northern Indiana.

Primary threats in the watch area include:

• Numerous damaging wind gusts with a few gusts to 75 mph possible.
• Hail of up to one inch in diameter
• The possibility of a few tornadoes.

At 6:56 p.m. EDT the Northern Indiana NWS office tweeted the following message:

Several reports of overturned semi trucks, downed power lines, and downed trees in the west suburbs of Chicago

 .    INDIANA COUNTIES INCLUDED IN THE WATCH ARE
     
     ADAMS                ALLEN               BLACKFORD           
     BOONE                CARROLL             CASS                
     CLINTON              DE KALB             ELKHART             
     FOUNTAIN             FULTON              GRANT               
     HOWARD               HUNTINGTON          JAY                 
     KOSCIUSKO            LAGRANGE            LA PORTE            
     MARSHALL             MIAMI               MONTGOMERY          
     NOBLE                PARKE               PULASKI             
     ST. JOSEPH           STARKE              STEUBEN             
     TIPPECANOE           TIPTON              VERMILLION          
     WABASH               WARREN              WELLS               
     WHITE                WHITLEY 

   .    OHIO COUNTIES INCLUDED ARE
     
     ALLEN                DEFIANCE            FULTON              
     HENRY                PAULDING            PUTNAM              
     VAN WERT             WILLIAMS     

The National Weather Service Storm Prediction Center issued severe thunderstorm watch number 356 at 4:15 p.m. EDT. In addition to a large part of northeastern Illinois and parts of southern Wisconsin and Lake Michigan, the watch includes five Indiana counties in the northwestern corner of the state: Benton, Jasper, Lake, Newton and Porter. The watch is in effect until 11 p.m. EDT (10 p.m. CDT).

Primary threats include

• Numerous damaging wind gusts with a few gusts to 80 mph possible.
• Large hail of up to two inches in diameter.
• The possibility of a few tornadoes.

If you’re having trouble hearing the NOAA Weather Radio transmiter in Fort Wayne (on 162.55 MHz), there’s a good reason. See the message below from the northern Indiana National Weather Service office:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE NORTHERN INDIANA
315 PM EDT MON JUN 24 2013 /215 PM CDT MON JUN 24 2013/

...FORT WAYNE WEATHER RADIO TRANSMITTER CONTINUES TO EXPERIENCE
POWER ISSUES...

THE NOAA WEATHER RADIO TRANSMITTER AT FORT WAYNE...WXJ-58 AT 162.550
MHZ...WILL CONTINUE TO BROADCAST AT LOW POWER DUE TO EQUIPMENT
PROBLEMS AT THE SITE. THIS IS RESULTING IN A DEGRADED BROADCAST
SIGNAL FROM THE TRANSMITTER. THE PROBLEM HAS BEEN IDENTIFIED AND
PARTS ARE ON ORDER TO REPAIR THE EQUIPMENT PROBLEMS. THE EXPECTED
RETURN TO SERVICE IS UNKNOWN AT THIS TIME...BUT REPAIRS ARE HOPED
TO BE MADE BY END OF THE WEEK.

ALTERNATE NOAA RADIO BROADCASTS AROUND THE FORT WAYNE REGION ARE
AS FOLLOWS: WXM-98 FROM MARION AT 162.450...KXI-94 FROM ANGOLA AT
162.425 MHZ...WXJ-90 FROM CRIDERSVILLE AT 162.400 MHZ. WE
APOLOGIZE FOR ANY INCONVENIENCE THIS MAY CAUSE. THIS STATEMENT
WILL BE UPDATED WHEN MORE INFORMATION IS AVAILABLE.

The National Weather Service Storm Prediction Center (SPC) has expanded the area of Indiana that is at slight risk of receiving severe weather tomorrow. Previously, the SPC’s Day 2 Convective Outlook placed the northern third of Indiana at slight risk between 8 a.m. EDT tomorrow (Tuesday, June 25) and 8 a.m. EDT Wednesday (June 26). At  1:27 p.m. EDT, the SPC issued an updated outlook that indicates a slight risk for the northern half of Indiana, including all 37 Indiana, Michigan and Ohio Counties covered by the northern Indiana NWS weather forecast office.

Our next look at the risk for northern Indiana should come at about 2 a.m. tomorrow morning, when SPC issues the first Day 1 Convective Outlook of the day.