Yellow area: 15% probability of severe weather within 25 miles of a point. Red area: 30% probability of severe weather within 25 miles of a point. Read about how the NWS defines the probabilities.

See an important update to this post.

The entire state of Indiana has a slight risk of severe thunderstorms between 7 a.m. EST Thursday, Feb. 20 and 7 a.m. EST Friday, Feb. 21, according to the Day 2 Convective Outlook that the National Weather Service (NWS) Storm Prediction Center (SPC) issued at 1:51 a.m. EST today.

As you can see on the map at right, the southern two-thirds of Indiana, plus adjacent parts of Illinois, Kentucky and Ohio, have a 30 percent probability of severe weather within 25 miles of a point, while the remainder of Indiana and adjacent areas of Illinois, Michigan and Ohio, have a 15 percent probability. The 30 percent area includes some of the southeastern counties of IMO SKYWARN quadrant two, including Blackford, Jay, and parts of Wells, Adams and Van Wert counties.

Why 15% and 30% are significant

It’s been months since I’ve written about convective outlooks, so here’s a reminder of what this all means.
In this case, the NWS defines “severe weather” as a tornado, damaging thunderstorm winds or wind gusts of 50 knots (58 mph) or higher, or one inch diameter hail or larger. The Day 2 Convective Outlook does not separate these, so a 30 percent probability indicates a risk of any one of the above types of severe weather. Also, risks of 15 and 30 percent might seem small, until you understand how low the probabilities normally are. For example, think of annual climatology. On how many days over the past year did at least one of the types of severe weather above occur within 25 miles of you? For illustration, let’s say that happened on 10 days in the past year. That would mean the normal probability for that area is 10/365, or 2.7 percent! A 15 percent probability, therefore, would indicate that severe weather is 5.5 times more likely than normal. A 30 percent probability would indicate that severe weather is 11.1 times more likely. You can read much more about these probabilities on the SPC website.

Brief summary of tomorrow’s weather setup

Here’s a brief summary of the outlook: A fairly widespread severe weather episode appears likely, primarily Thursday afternoon and evening and into the early morning hours of Friday. A strong cold front and associated, powerful upper storm system will move across the central U.S. and into the eastern U.S. By late afternoon, a nearly solid and fast-moving line of thunderstorms should stretch from the southern upper Great Lakes vicinity south-southwestward into the central and western Gulf coastal region. This line will bring a risk for fairly widespread damaging wind gusts. In addition, a few embedded tornadoes will be possible within the line — particularly within a zone in the mid-Ohio valley and mid Tennessee valley vicinity.

Plus, there’s a flood risk

Rainfall associated with a severe thunderstorm could increase the risk of flooding in northeastern Indiana, southern lower Michigan and northwestern Ohio. As the northern Indiana NWS office wrote in this morning’s Hydrologic Outlook,

The threat for flooding appears to be increasing in many areas, but is not certainty at this point. The severity and timing of flooding will depend on the amount of rainfall received Thursday, and the exact duration of warmer conditions, which remains uncertain. If you live in a flood prone area, now is the time to prepare for possible flooding. Stay alert to the latest forecasts trends over the next several days by visiting weather.gov/iwx.

The bottom line

How should you use the information in today’s Day 2 Convective Outlook? If you’re a SKYWARN storm spotter, check your gear (including communication equipment), gas up your vehicle and get ready for activation. Whether or not you’re not a spotter, make sure your NOAA weather radio is working (replace its batteries, if it’s been more than a year since you’ve done so), make a mental note to check your local forecast tomorrow morning (e.g. on www.weather.gov), and if the risk of severe weather remains in place, be sure you have a way to receive any watches or warnings that might come out. Above all, don’t assume that because it’s February, tornadoes and severe thunderstorms won’t happen!

Reminder: The first spotter show of the year takes place tonight at 7 p.m. EST in Columbia City.!

The Saint Mary’s River flooded Tillman Road in Fort Wayne in March, 1982 (NWS photo).

As you can see in the Hyrdologic Outlook below, melting snow today and tomorrow, combined with rain on Thursday, could cause some flooding this week. Much remains uncertain, however, including the amount of rainfall we receive Thursday and how long temperatures remain above freezing. Keep an eye on the National Weather Service website for the latest information.

ESFIWX
INC001-003-009-017-033-039-049-053-069-075-085-087-091-099-103-
113-131-141-149-151-169-179-181-183-MIC021-023-027-059-149-OHC003-
039-051-069-125-137-161-171-190945-
ADAMS-ALLEN IN-BLACKFORD-CASS IN-DE KALB-ELKHART-FULTON IN-GRANT-
HUNTINGTON-JAY-KOSCIUSKO-LAGRANGE-LA PORTE-MARSHALL-MIAMI-NOBLE-
PULASKI-ST. JOSEPH IN-STARKE-STEUBEN-WABASH-WELLS-WHITE-WHITLEY-
BERRIEN-BRANCH-CASS MI-HILLSDALE-ST. JOSEPH MI-ALLEN OH-DEFIANCE-
FULTON OH-HENRY-PAULDING-PUTNAM-VAN WERT-WILLIAMS-

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE NORTHERN INDIANA
440 AM EST TUE FEB 18 2014 /340 AM CST TUE FEB 18 2014/

...INCREASED FLOOD POTENTIAL BY THURSDAY...

SEVERAL FACTORS WILL COMBINE TO CREATE AN INCREASED FLOOD RISK
STARTING LATER THIS WEEK. WIDESPREAD SNOW AND ICE CONTAIN A LARGE
QUANTITY OF STORED WATER...GENERALLY 1.5 TO 4.0 INCHES ACROSS THE
REGION WITH THE GREATEST WATER CONTENT ACROSS FAR NORTHERN INDIANA
AND SOUTHERN LOWER MICHIGAN.

WARMER TEMPERATURES ARE EXPECTED TUESDAY AND WEDNESDAY WITH
AFTERNOON HIGHS RISING ABOVE THE FREEZING MARK. NIGHTTIME
TEMPERATURES ARE EXPECTED TO DROP BELOW FREEZING DURING THIS
PERIOD HOWEVER...WHICH SHOULD LIMIT THE AMOUNT OF SNOWMELT AND
RUNOFF THROUGH WEDNESDAY.

MUCH WARMER CONDITIONS ARE ANTICIPATED BY THURSDAY WHICH WILL ACT
TO INCREASE THE RATE OF SNOWMELT. SOME MODERATE TO HEAVY RAINFALL
IS ALSO POSSIBLE THURSDAY AS A STRONGER UPPER LEVEL DISTURBANCE
APPROACHES THE REGION. THIS POTENTIAL RAINFALL COMBINED WITH
INCREASED RUNOFF FROM MELTING SNOW ATOP THE FROZEN GROUND MAY LEAD
TO A HEIGHTENED POTENTIAL FOR FLOODING IN LOW LYING
AREAS...BASEMENTS AND SMALL STREAMS AND CREEKS. SIGNIFICANT RISES
ALONG MAJOR STEM RIVERS COULD FOLLOW.

THESE WARMER CONDITIONS AND RUNOFF LATER IN THE WEEK WILL LEAD TO
SOME POTENTIAL FOR BREAK UP AND DOWNSTREAM MOVEMENT OF THICK ICE
ON RIVERS THAT WOULD INCREASE THE RISK FOR ICE JAMS TO DEVELOP AND
INCREASE THE FLOODING POTENTIAL.

FUTURE FLOODING IS A POSSIBILITY AT THIS TIME...NOT A CERTAINTY. 
THE SEVERITY AND TIMING OF FLOODING WILL DEPEND ON THE AMOUNT OF
RAINFALL RECEIVED THURSDAY...AND THE EXACT DURATION OF WARMER
CONDITIONS...WHICH REMAINS UNCERTAIN. IF YOU LIVE IN A FLOOD PRONE
AREA...NOW IS THE TIME TO PREPARE FOR POSSIBLE FLOODING. STAY
ALERT TO THE LATEST FORECASTS TRENDS OVER THE NEXT SEVERAL DAYS BY
VISITING WEATHER.GOV/IWX.

ADDITIONAL FLOOD AWARENESS INFORMATION IS AVAILABLE AT
WEATHER.GOV/FLOODSAFETY AND READY.GOV/FLOODS

The Winter Weather Advisory below is different, depending on what county you’re in, so be sure to scroll down and find your county. I’ve highlighted the section that pertains to Allen County, Indiana.

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE NORTHERN INDIANA
340 PM EST SUN FEB 16 2014

...SNOW FOR MONDAY EVENING COMMUTE...

.LOW PRESSURE WILL RAPIDLY TRACK NORTHEAST FROM THE SOUTHERN
PLAINS MONDAY MORNING TO SOUTHWEST OHIO BY MONDAY EVENING. SNOW
WILL RAPIDLY OVERSPREAD THE REGION MIDDAY THROUGH THE AFTERNOON
HOURS...AND MAY BECOME BRIEFLY HEAVY AT TIMES. A MIX OF SLEET IS
ALSO POSSIBLE...PRIMARILY ALONG AND SOUTH OF A MONTICELLO TO FORT
WAYNE TO OTTAWA OHIO LINE. WHILE THE PRESENCE OF SLEET WILL KEEP
SNOW AMOUNTS TO THE LOWER END...TRAVEL WILL LIKELY BECOME EVEN
MORE DIFFICULT AS THE ROADS BECOME PACKED WITH SNOW AND ICE. AS
THE SNOW COMES TO AN END THERE MAY BE A BRIEF PERIOD OF LIGHT
FREEZING DRIZZLE AS WELL.

INZ020-022>024-170445-
/O.NEW.KIWX.WW.Y.0009.140217T1600Z-140218T0400Z/
WHITE-CASS IN-MIAMI-WABASH-
INCLUDING THE CITIES OF...MONTICELLO...BROOKSTON...MONON...
LOGANSPORT...ROYAL CENTER...PERU...GRISSOM AFB...MEXICO...
WABASH...NORTH MANCHESTER
340 PM EST SUN FEB 16 2014

...WINTER WEATHER ADVISORY IN EFFECT FROM 11 AM TO 11 PM EST
MONDAY...

THE NATIONAL WEATHER SERVICE IN NORTHERN INDIANA HAS ISSUED A
WINTER WEATHER ADVISORY FOR SNOW AND POSSIBLE SLEET...WHICH IS IN
EFFECT FROM 11 AM TO 11 PM EST MONDAY.

HAZARDOUS WEATHER...

 * PRIMARILY SNOW...THOUGH SLEET ALSO POSSIBLE. PRECIPITATION MAY
   END WITH A PERIOD OF LIGHT FREEZING DRIZZLE.

 * SNOW AND SLEET ACCUMULATIONS 2 TO 4 INCHES.

IMPACTS...

 * SNOW AND SLEET ON ROADS WILL LEAD TO VERY SLIPPERY DRIVING
   CONDITIONS FOR THE MONDAY EVENING COMMUTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...SLEET...OR
FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR
SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

INZ017-018-025>027-032>034-OHZ015-016-024-025-170445-
/O.NEW.KIWX.WW.Y.0009.140217T1800Z-140218T0800Z/
WHITLEY-ALLEN IN-HUNTINGTON-WELLS-ADAMS-GRANT-BLACKFORD-JAY-
PAULDING-PUTNAM-VAN WERT-ALLEN OH-
INCLUDING THE CITIES OF...COLUMBIA CITY...TRI-LAKES...
SOUTH WHITLEY...FORT WAYNE...NEW HAVEN...HUNTINGTON...ROANOKE...
BLUFFTON...OSSIAN...DECATUR...BERNE...MARION...GAS CITY...
UPLAND...HARTFORD CITY...MONTPELIER...PORTLAND...DUNKIRK...
PAULDING...ANTWERP...MELROSE...OTTAWA...PANDORA...KALIDA...
FORT JENNINGS...VAN WERT...DELPHOS...OHIO CITY...LIMA...
SPENCERVILLE
340 PM EST SUN FEB 16 2014

...WINTER WEATHER ADVISORY IN EFFECT FROM 1 PM MONDAY TO 3 AM EST
TUESDAY...

THE NATIONAL WEATHER SERVICE IN NORTHERN INDIANA HAS ISSUED A
WINTER WEATHER ADVISORY FOR SNOW AND POSSIBLE SLEET...WHICH IS IN
EFFECT FROM 1 PM MONDAY TO 3 AM EST TUESDAY.

HAZARDOUS WEATHER...

 * PRIMARILY SNOW...THOUGH SLEET ALSO POSSIBLE. PRECIPITATION MAY
   END WITH A PERIOD OF LIGHT FREEZING DRIZZLE.

 * SNOW AND SLEET ACCUMULATIONS 2 TO 4 INCHES.

IMPACTS...

 * SNOW AND SLEET ON ROADS WILL LEAD TO VERY SLIPPERY DRIVING
   CONDITIONS FOR THE MONDAY EVENING COMMUTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...SLEET...OR
FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR
SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

INZ003>005-012>016-MIZ077-078-170445-
/O.NEW.KIWX.WW.Y.0009.140217T1600Z-140218T0400Z/
LA PORTE-ST. JOSEPH IN-ELKHART-STARKE-PULASKI-MARSHALL-FULTON IN-
KOSCIUSKO-BERRIEN-CASS MI-
INCLUDING THE CITIES OF...MICHIGAN CITY...LA PORTE...SOUTH BEND...
MISHAWAKA...NEW CARLISLE...WALKERTON...ELKHART...GOSHEN...
NAPPANEE...KNOX...NORTH JUDSON...BASS LAKE...WINAMAC...
FRANCESVILLE...MEDARYVILLE...PLYMOUTH...BREMEN...CULVER...
ROCHESTER...AKRON...WARSAW...WINONA LAKE...SYRACUSE...MENTONE...
NILES...BENTON HARBOR...ST. JOSEPH...BUCHANAN...DOWAGIAC...
CASSOPOLIS...MARCELLUS
340 PM EST SUN FEB 16 2014 /240 PM CST SUN FEB 16 2014/

...WINTER WEATHER ADVISORY IN EFFECT FROM 11 AM EST /10 AM CST/
TO 11 PM EST /10 PM CST/ MONDAY...

THE NATIONAL WEATHER SERVICE IN NORTHERN INDIANA HAS ISSUED A
WINTER WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT FROM 11 AM
EST /10 AM CST/ TO 11 PM EST /10 PM CST/ MONDAY.

 * SNOW...MAY BE BRIEFLY HEAVY AT TIMES. SNOW MAY END WITH A
   PERIOD OF LIGHT FREEZING DRIZZLE.

 * SNOW ACCUMULATIONS 3 TO 5 INCHES.

 * VISIBILITIES MAY BE REDUCED TO ONE-QUARTER MILE OR LESS IN
   SNOW.

IMPACTS...

 * SNOW COVERED ROADS WILL LEAD TO VERY DIFFICULT DRIVING
   CONDITIONS FOR THE MONDAY EVENING COMMUTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

INZ006>009-MIZ079>081-OHZ001-002-004-005-170445-
/O.NEW.KIWX.WW.Y.0009.140217T1800Z-140218T0800Z/
LAGRANGE-STEUBEN-NOBLE-DE KALB-ST. JOSEPH MI-BRANCH-HILLSDALE-
WILLIAMS-FULTON OH-DEFIANCE-HENRY-
INCLUDING THE CITIES OF...LAGRANGE...TOPEKA...SHIPSHEWANA...
ANGOLA...FREMONT...KENDALLVILLE...LIGONIER...ALBION...AUBURN...
GARRETT...STURGIS...THREE RIVERS...WHITE PIGEON...MENDON...
COLDWATER...BRONSON...HILLSDALE...LITCHFIELD...JONESVILLE...
BRYAN...MONTPELIER...WAUSEON...ARCHBOLD...FAYETTE...SWANTON...
DEFIANCE...SHERWOOD...HICKSVILLE...NAPOLEON...DESHLER...
LIBERTY CENTER
340 PM EST SUN FEB 16 2014

...WINTER WEATHER ADVISORY IN EFFECT FROM 1 PM MONDAY TO 3 AM EST
TUESDAY...

THE NATIONAL WEATHER SERVICE IN NORTHERN INDIANA HAS ISSUED A
WINTER WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT FROM 1 PM
MONDAY TO 3 AM EST TUESDAY.

HAZARDOUS WEATHER...

 * SNOW...MAY BE BRIEFLY HEAVY AT TIMES. SNOW MAY END WITH A
   PERIOD OF LIGHT FREEZING DRIZZLE.

 * SNOW ACCUMULATIONS 3 TO 5 INCHES.

 * VISIBILITIES MAY BE REDUCED TO ONE-QUARTER MILE OR LESS IN
   SNOW.

IMPACTS...

 * SNOW COVERED ROADS WILL LEAD TO VERY DIFFICULT DRIVING
   CONDITIONS FOR THE MONDAY EVENING COMMUTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

The northern Indiana office of the National Weather Service has issued a Hydrologic Outlook that explains an increased risk of flooding in northeastern Indiana and northwestern Ohio. As the outlook explains, it’s too early to issue a flood watch or warning, but flooding is possible. So people who live in flood-prone areas should be prepared for flooding and monitor official forecasts over the next couple weeks.

Here’s the verbatim statement:

ADAMS-ALLEN IN-BLACKFORD-CASS IN-DE KALB-ELKHART-FULTON IN-GRANT-
HUNTINGTON-JAY-KOSCIUSKO-LAGRANGE-LA PORTE-MARSHALL-MIAMI-NOBLE-
PULASKI-ST. JOSEPH IN-STARKE-STEUBEN-WABASH-WELLS-WHITE-WHITLEY-
BERRIEN-BRANCH-CASS MI-HILLSDALE-ST. JOSEPH MI-ALLEN OH-DEFIANCE-
FULTON OH-HENRY-PAULDING-PUTNAM-VAN WERT-WILLIAMS-

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE NORTHERN INDIANA
415 AM EST FRI FEB 14 2014 /315 AM CST FRI FEB 14 2014/

...INCREASED FLOOD POTENTIAL INTO LATE FEBRUARY...

SEVERAL FACTORS WILL COMBINE TO CREATE AN INCREASED FLOOD RISK
STARTING LATE NEXT WEEK AND CONTINUING THROUGH THE END OF
FEBRUARY. WIDESPREAD SNOW AND ICE CONTAIN A LARGE QUANTITY OF
STORED WATER...GENERALLY 1.5 TO 3.5 INCHES ACROSS THE REGION. A
WINTRY MIX WILL DEVELOP EARLY MONDAY AND LIKELY CHANGE TO ALL
RAIN BY MONDAY AFTERNOON ACROSS SOUTHERN PORTIONS OF THE
AREA. A WINTRY MIX MAY PERSIST INTO MONDAY AFTERNOON ACROSS
NORTHERN PORTIONS OF THE AREA. THIS PRECIPITATION WILL FURTHER ADD
TO THE AMOUNT OF WATER LOCKED IN PLACE BY THE SNOW COVER.

A WARM-UP WILL ALSO COMMENCE BY THE MIDDLE OF NEXT WEEK AND
LIKELY CONTINUE INTO NEXT WEEKEND THAT WILL RESULT IN MELTING OF
THE SNOWPACK ACROSS THE AREA. INCREASED RUNOFF FROM THIS MELTING
SNOW ATOP THE FROZEN GROUND WILL LEAD TO A HEIGHTENED POTENTIAL
FOR FLOODING IN LOW LYING AREAS...BASEMENTS AND SMALL STREAMS AND
CREEKS. SIGNIFICANT RISES ALONG MAJOR STEM RIVERS COULD FOLLOW.

SHOULD A SIGNIFICANT RAIN EVENT OCCUR DURING THIS WARMER
PERIOD...THE POTENTIAL FOR...AND THE SEVERITY OF...RESULTANT
FLOODING WOULD GREATLY INCREASE. THE POTENTIAL FOR BREAK UP AND
DOWNSTREAM MOVEMENT OF THICK ICE ON RIVERS WOULD INCREASE THE
RISK FOR ICE JAMS TO DEVELOP AND FURTHER EXACERBATE THE FLOODING
RISK.

FUTURE FLOODING IS A POSSIBILITY AT THIS TIME...NOT A CERTAINTY.
IF YOU LIVE IN A FLOOD PRONE AREA...NOW IS THE TIME TO PREPARE
FOR POSSIBLE FLOODING. STAY ALERT TO THE LATEST FORECASTS TRENDS
OVER THE NEXT SEVERAL DAYS BY VISITING WEATHER.GOV/IWX.

ADDITIONAL FLOOD AWARENESS INFORMATION IS AVAILABLE AT
WEATHER.GOV/FLOODSAFETY AND READY.GOV/FLOODS

The first of two SKYWARN storm spotter training sessions in the Fort Wayne area happens Tuesday, Feb. 18, at 7 p.m. at Columbia City High School, 600 N. Whitley St., Columbia City, Ind.

Everyone is welcome. The training will help participants learn how to identify tornadoes and other severe weather phenomena and how to report them to the National Weather Service (NWS) to aid in public safety. You do not need to be ham radio operator. Spotters who are not hams can make reports via telephone or social media. 

Registration is not required but is highly recommended.  Why? If a winter storm requires the NWS to cancel the training, registrants will receive notification via email. If you don’t register, you risk wasting a trip to Columbia City.

To register for the Columbia City session, follow this link.

The National Weather Service requests that all participants complete online storm spotter training before attending a live training session. If you completed the online training last year and are confident that you remember the material, it is not necessary to view the online training again this year.

To view the two modules of the online spotter training course, follow this link.

The NWS will not conduct a spotter training session in Fort Wayne in 2014. If you are unable to attend the Columbia City session, the next session close to Fort Wayne happens Monday, March 17, at 6 p.m. (note the earlier starting time), at Wells County Community Center, 1240 S. 4-H Road, Bluffton, Ind.

To register for the Bluffton session, follow this link.

If you have questions about SKYWARN spotter training, contact Michael Lewis, the warning coordination meteorologist at National Weather Service northern Indiana weather forecast office.