Risk of severe weather between 8 a.m. EDT Tuesday and 8 a.m. EDT Wednesday. Yellow area: Slight risk. Green area: Non-severe thunderstorms.

Much of eastern Indiana and almost all of Ohio remains under a slight risk of severe weather from 8 a.m. EDT Tuesday to 8 a.m. EDT Wednesday, according to an updated Day 2 Convective Outlook the National Weather Service Storm Prediction Center (SPC) issued at 1:29 p.m. EDT.

Tomorrow afternoon, some surface heating in the wake of thunderstorms earlier in the day should provide sufficient buoyancy for isolated severe storms with damaging winds and severe hail. Some tornado risk might evolve from parts of middle Tennessee to the Ohio valley and possibly Lower Michigan, but this will be contingent on more appreciable daytime atmospheric destabilization, for which uncertainty remains.

Our next look at tomorrow’s serve weather risk will come at about 2 a.m. EDT tomorrow, when the SPC issues its first Day 1 Convective Outlook for the period.

The northern Indiana office of the National Weather Service issued a tweet this afternoon that indicates severe weather has ceased to be an issue today in any of the 37 counties in its county warning area (see map below). Here’s the tweet:

This morning’s rain has stabilized the atmosphere locally. Severe weather threat for remainder of day expected to remain S of the area
— NWS Northern Indiana (@NWSIWX) April 28, 2014

Risks of severe weather between 8 a.m. EDT today and 8 a.m. EDT Tuesday. Yellow area: slight risk. Red area: moderate risk.

Much of Indiana has a slight risk of severe storms between 8 a.m. EDT today and 8 a.m. EDT tomorrow, according to a Day 1 Convective Outlook the National Weather Service Storm Prediction Center (SPC) issued at 8:37 a.m. EDT. In addition, much of the eastern half of Indiana has a slight risk of severe weather during the  subsequent 24-hour period, between 8 a.m. EDT Tuesday and 8 a.m. EDT Wednesday, according to this morning Day 2 Convective Outlook.

Area covered today
As you can see on the map graphic at right, The northern edge of today’s slight risk area includes all or parts (at least half) of the following Indiana counties: Jasper, White, Cass, Howard, Grant, Delaware and Randolph. Indiana counties to the north of these are either not included or only small parts are included. Today’s slight risk area includes all Indiana counties to the south of the counties listed above. In Ohio, today’s slight risk area includes Darke, Miami, Clark and Greene Counties and other counties to the south of those.

Today’s risks
The main severe weather risks in Indiana today and tonight are damaging thunderstorm winds or wind gusts of 50 knots (58 mph) or higher and one inch diameter or larger hail. The probability of either of those within 25 miles of a point is 15 percent, except for a few counties in west central Indiana, where the hail risk reaches 30 percent.

Timing
A band of showers and low-topped thunderstorms are forecast to develop during the afternoon today in the vicinity of eastern Iowa and western Illinois. Those storms will move east and are forecast to weaken at around sunset.

Tomorrow
This morning’s Day 2 Convective Outlook puts all but the easternmost counties of Ohio and much of eastern Indiana under slight risk of severe weather between 8 a.m. EDT Tuesday and 8 a.m. EDT Wednesday. Indiana Counties at last half of which are covered include: Steuben, DeKalb, Whitley, Allen, Huntington, Adams, Wells, Grant, Blackford, Jay and counties to the south of these, all the way to Louisville and Cincinnati. The probability of any kind of severe weather within 25 miles of a point is 15 percent. The greatest risk for severe weather during this period will be Tuesday afternoon through early evening.

Next looks
The SPC will issue an updated Day 1 Convective Outlook by 12:30 p.m. EDT. The next look at Tuesday’s severe weather risk comes in an updated Day 2 Convective Outlook by 1:30 p.m.

Elsewhere
If you have family in Tennessee, Mississippi or Alabama, you’ll want to know that there’s a moderate risk of tornadoes in parts of those states today, including tornadoes capable of producing up to EF5 damage. Its particularly important for people in those areas to remain aware of the weather situation today.

Example convective outlook map. Notice the new dark green “MRGL” (marginal) and orange “ENH” (enhanced) risk areas.

The National Weather Service Storm Prediction Center (SPC) plans significant changes to its Convective Outlook product, from which many SKYWARN storm spotters and others get their first indications that severe weather could occur.

The SPC plans to expand the product’s risk categories from four to five, while clarifying the category previously labeled as “See Text.” Convective outlooks would instead have a new “marginal” category to denote areas with at least a five percent probability of severe weather. The upper end of the current “Slight Risk” category would be renamed “Enhanced” (short for “Enhanced Slight”) to denote a threshold 30 percent probability of severe wind or hail and/or a 10 percent chance of a tornado during the Day 1 period. For Days 2 and 3, the “Enhanced” risk category would denote a 30 percent total severe probability. The Moderate and High risk thresholds will remain essentially unchanged.

The SPC wants users of the Convective Outlook product, including storm spotters, to provide their opinions on the planned changes. Read details about the changes on the SPC website, where you can also follow a link to a survey.

The northern Indiana office of the National Weather Service (NWS) has a new way for SKYWARN storm spotters to send reports via the Internet. A new spotter report form on the office’s website succeeds the old eSpotter website. I wrote previously that the NWS plans to shut down the eSpotter site soon.

The new Web form allows you to report a number of weather phenomena, including:

• Dense Fog
• Flood
• Hail
• High wind speed
• Tornado
• Funnel cloud
• Wind damage
• Snow
• Freezing rain
• Rainfall totals

Reports entered into the new form appear on an Advanced Weather Interactive Processing System (AWIPS) workstation at the weather forecast office, where a meteorologist will notice it immediately.

To get to the new form, visit the office’s home page at www.weather.gov/iwx and click on the “Submit Report” link in the left-hand menu (under “Current Hazards”). Or just click here and bookmark the page.

Meteorologists in Illinois documented the first radar hook echo on this date in 1953. This was a major turning point in monitoring severe weather, demonstrating that tornadoes could be identified by radar. This discovery helped lead to the first national weather radar network in the United States.

Read more on the blog of the Illinois State Climatologist »

First recorded radar hook echo of a tornado, April 9, 1953, near Champaign, IL (photo courtesy of the Illinois State Water Survey, INRS, University of Illinois).

Aurora, Mo. tornado, May 4, 2003 (NWS photo)

Meteorologist Eric Holthaus recently wrote an article for “Slate” in which he criticizes a bill in Congress that would require the National Oceanic and Atmospheric Administration (NOAA, parent agency of the National Weather Service) to spend more on improving forecasts of “high impact weather events” like tornadoes and hurricanes.

On its face, the bill sounds like a good idea and you might wonder why anyone would oppose making tornado and hurricane forecasts better.

But Holthaus correctly writes that the bill would force NOAA to spend less on improving forecasts of lower-profile weather and climate disasters that, in aggregate, kill dozens of times more people per year.

I’ve noticed that it’s not unusual for lawmakers to pass bills that make it look to the general public like the we are better protected from some harm when those laws really don’t enhance our safety as much as they improve lawmakers’ chances for reelection. This appears to be an example of that.

I highly recommend that you read Holthaus’ article and then consider contacting your U.S. representative. Tell your congressman that the House should not pass H.R.2413, the “Weather Forecasting Improvement Act of 2014,” unless Congress also provides additional funding for its mandates, so that research into more deadly, lower-impact events does not suffer.

The St. Mary’s River spills into Fort Wayne’s Swinney Park, midday, April 4, 2014. (W9LW photo)

The northern Indiana office of the National Weather Service (NWS) issued new statements at midday regarding river flooding in its area. In general, forecasts for flooding are now far less severe.

The NWS canceled the flood warning for the St. Mary’s River at the Muldoon Bridge gauge (just south and upstream of Fort Wayne).

The NWS revised the forecast for the Little River near Huntington from major flooding to minor flooding.

See the latest NWS flood statements.

Spy Run Creek backs up against the State Blvd. bridge in northern Fort Wayne at 4 p.m., April 3, 2014. (W9LW photo)

See an update to this post.

Heavy rain forecast overnight remained in southern parts of Indiana, which eased some flooding concerns in northeastern Indiana and northwestern Ohio. But although the potential for heavy rainfall in the area had diminished by early morning, meteorologists indicated that run-off from yesterday’s heavy rainfall will cause river flooding today. Flood warnings therefore remain in effect for many rivers in the area.

The worst problem continues to be in the Huntington area. As of 10:44 p.m. (the most recent NWS statements at the time of this writing), major flooding was forecast along the Little River. The river was forecast to rise to only 0.1 foot below the level at which extensive inundation and damage occurs, many primary roads and bridges close and many evacuations occur.

In Fort Wayne, moderate flooding was forecast along the St. Mary’s River, which was forecast to rise to six inches below the level at which extensive evacuations become necessary and primary roads and bridges are closed. Minor flooding was forecast along the Maumee and St. Joe Rivers. The Maumee was forecast to rise within 0.2 feet of the flood experienced Feb. 8, 2008. The St. Joe was forecast to rise as high as it did May 27, 2011.

Here is a link to the latest updates from the NWS on river flooding. Here is a link to an interactive map on which you can see the latest river gauge readings.

The National Weather Service is requesting reports of flooding, including roads blocked by high water. You can make the reports on Twitter by including the hash tag #nwsiwx (include a photo, when possible) or follow this link to fill out a Web form.

Although river flooding remained forecast, At 3:30 a.m. EDT, the northern Indiana National Weather Service office allowed an areal flood warning for urban areas and small streams to expire for the following counties: Allen (Ind. and Ohio), southeastern Defiance, Paulding, Van Wert, Henry, Putnam, Blackford, Jay, Grant, southeastern Cass, Wells, Adams, southern Miami, southern Huntington, southern Wabash and Allen.

At 3:45 a.m., the NWS canceled the areal flood watch that had been in effect for the following Ohio counties: Fulton and Williams and the following Indiana counties: De Kalb, Elkhart, Fulton, Kosciusko, Lagrange, Noble, Pulaski, Steuben and White.

At 6:46 a.m., the NWS canceled the remainder of its areal flood watch, which included the following Ohio counties: Allen, Defiance, Henry, Paulding, Putnam and Van Wert and the following Indiana counties: Adams, Allen, Blackford, Cass, Grant, Huntington, Jay, Miami, Wabash, Wells and Whitley.