Tag Archives: #INwx

A weather safety tip you might not have thought of: Footwear

Photo of feet wearing flip-flops with red X superimposed. Flip-flops are poor footwear for severe weather days. Indiana Severe Weather Preparedness Week. #INWxReady #WRNSandals, especially flip-flops, which are so popular when the weather is warm, are poor choices for severe weather days.

My feet get warm easily. I have a pair of Chacos brand sandals that I wear almost every day during warm weather. But not on days that I might need to serve as a storm spotter.

If severe weather is coming our way, I usually change into a sturdy pair of ankle-supporting hunting boots I bought on sale at Cabela’s, even if I’ll be staying home during the storm.

Why? On word: debris.

National Weather Service photo

After a storm passes, I might have to walk through storm debris, which can include pieces of trees and pieces of buildings. The walking surface might be uneven. Some of the debris might have sharp edges.

I choose to protect my feet from all that, a practice I learned back in the 90s when I served as an emergency medical technician and communications technician on a Disaster Medical Assistance Team. It’s how I dressed my feet every day, even in tropical weather when assisting the victims of Hurricanes Andrew and Marilyn.

My advice: If you’re a storm spotter or storm chaser, get yourself a good pair of boots to wear anytime you’re in the field, even on hot, humid days. And no matter who you are, if you ever have to take shelter in your house from a coming storm, take the most protective footwear you have with you to the basement, interior room, etc. Put them on after the storm, before you step outside to survey the damage. Your feet will be much safer.

An even earlier “heads up” on severe weather

Earlier, in commemoration of Indiana Severe Weather Preparedness Week, I wrote about the important distinctions between watches and warnings. Readers who saw that post will recall that the National Weather Service usually issues weather watches hours before severe weather develops in the watch area.

You can also know about the possibilities of severe weather days in advance, if you know where to look.

In addition to watches, the NWS Storm Prediction Center (SPC) issues convective outlooks. In this case, “convective,” refers to thunderstorm development through atmospheric instability. Convective outlooks include maps that show various risk levels for severe thunderstorms in various parts of the country as far into the future as six days.

For example, on April 27, 2014, a large, violent tornado killed 16 people in Vilonia and Mayflower, Arkansas. Five days earlier, the SPC indicated a risk of severe weather in that area on a convective outlook map (see below).

Day 4-8 convective outlook from April 22, 1014 for Indiana Severe Weather Preparedness Week
“Day 4-8 Convective Outlook” map issued by the Storm Prediction Center on April 22, 2014, five days before a tornado killed 16 people in Arkansas. Note the green area labeled “D6,” which includes the area where the tornado eventually formed and which indicated a 30 percent or higher probability of severe thunderstorms within 25 miles of any point on April 27.

Anyone who wants an advance look at severe weather probabilities can look at SPC convective outlooks on the SPC website. During severe weather season, I review every morning at least the “Day 1 Convective Outlook” (which shows risks for the same day) and the “Day 2 Convective Outlook” (which shows the next day’s risks).

For a more localized outlook, I also view the “Hazardous Weather Outlook” that our local NWS office issues. This text-only product indicates local forecasters’ assessment of the risks of hazardous weather within their coverage area the same day (day one) and for the following week (days two through seven).

So, what can you do with this information? When an outlook indicates a risk of severe weather in a few days, you can:

  • Develop and/or review a plan for what to do if sever weather strikes.
  • Encourage others to develop a plan.
  • Assemble a disaster supply kit and pet kit.
  • Check your NOAA All Hazards radio for fresh batteries and operation.

By knowing about outlooks, watches and warnings when they’re issued, you can keep from being surprised by severe weather.

Severe weather watches and warnings: Do you really know the difference?

Tornado graphic for Indiana Severe Weather Preparedness Week 2015Governor Mike Pence has proclaimed March 15 through 21, 2015 as Severe Weather Preparedness Week in Indiana.

Throughout the week, I’ll use my “W9LW’s Ramblings” blog to help build awareness of important severe weather concepts that everyone should know.

If you’re a trained storm spotter, you’ll already know most of the stuff I’ll write about. In that case, I encourage you to use Indiana Severe Weather Preparedness Week to share this information with your family, friends and co-workers. After all, you are probably the closest thing to a weather expert who those folks know personally.

Today, I’ll start with one of the most basic of severe weather concepts, but also one of the most important; knowing the difference between a severe weather watch and a warning.

The National Weather Service (NWS) has used the term, “watch,” since August of 1965 but I still talk to people who don’t really understand what a watch is and others who refer to watches as warnings and warnings as watches.

Here’s a simple table to help you remember the difference. The information below applies to both tornado and severe thunderstorm warnings and watches.

Warning Watch
Your response Take shelter now! Remain alert, determine where you’ll take shelter if necessary
Meaning Severe weather is imminent, has been detected by radar and/or confirmed by trained weather spotters Conditions are favorable for the development of severe weather in and close to the watch area
Timeframe Minutes before danger arrives Usually hours before severe weather occurs
Geography Very local, sometimes less than a county, based on storm location and track Regional, multiple counties, often crossing state lines, based on atmospheric conditions

Bottom line: When the NWS issues a warning, it’s time to take action. Now. When the NWS issues a watch, it’s time to make sure you’ll know about a warning if one comes out later and time to make sure you know what you’ll do if a warning comes out.

Please share this! Do you know someone who doesn’t really understand watches and warnings? Use the buttons below to share a link with your social networks, etc.

NWS N. Ind. cancels Winter Weather Advisory, issues Wind Chill Warning

Map showing locations of wind chill warning and advisory

The storm system that dropped a few inches of snow in northern Indiana, southern Lower Michigan and northwestern Ohio moved on quickly this morning, leading the northern Indiana office of the National Weather Service (NWS) to cancel early its Winter Weather Advisories for all but Berrien County, Michigan.

The office issued a new Wind Chill Warning, however, for most of the counties in its coverage area, including Allen County, Indiana (see map above) and a Wind Chill Advisory for several other counties. They both take effect at 10 p.m. EST tonight and run until noon Thursday.

In the area covered by the Wind Chill Warning, the NWS expects prolonged, dangerous wind chill temperatures of -15 to -30 degrees Fahrenheit.  In the advisory area, the NWS expects prolonged wind chill temperatures of -10 to -25 degrees F.

As you can see in the chart below, at a wind chill of -18, frostbite can occur after 15 or fewer minutes of exposure.

Wind chill chart
Source: http://www.crh.noaa.gov/ddc/?n=windchill

 

NWS: Rain will change to snow, high winds will blow

NWS map graphic showing winter weather advisory and wind advisory
NWS graphic

Forecasters expect rain today, changing to snow this afternoon and evening in northern Indiana, southwestern Lower Michigan and northwestern Ohio, according to various text products from the northern Indiana office of the National Weather Service (NWS) (Facebook, Twitter).

They expect the change to snow to begin this afternoon in the western counties of the office’s 37-county warning area (CWA) and progress to the eastern counties by this evening.

The office has issued a Winter Weather Advisory for counties along the western edge of its CWA (see graphic above), where meteorologists expect one to three inches of snow with locally higher amounts. The winter weather advisory is in effect from 4 p.m. to midnight.

They issued a Wind Advisory for most of the CWA’s Ohio counties from 4 p.m. this afternoon to 3 a.m. tonight. There, they forecast sustained winds of 20 to 30 mph, with gusts up to approximately 45 mph.

The NWS issued a Special Weather Statement for the rest of the CWA that alerts readers to potentially difficult driving conditions by this evening, due to slushy roads and reduced visibilities.

NWS surface analysis map, 7 a.m. EST
NWS surface analysis map, 7 a.m. EST

Believe it or not, there is still some uncertainty regarding when the change from rain to snow will happen and therefore, how much snow will fall. That’s because there’s still a chance that the low pressure system that will be responsible for all this weather could follow a different path than forecast. “Just a 20-30 mile shift west or east will make all the difference,” writes NWS meteorologist Mark Steinwedel in an Area Forecast Discussion the northern Indiana office issued this morning.

As of 7 a.m. EST today, that area of low barometric pressure was just south of Indiana (see map above; black arrow points out the low). When meteorologists see what path the low actually takes, they’ll be better able to forecast snowfall timing and amounts.

Christmas Storm snowfall forecast remains difficult

Graphic: Snow background with word, "uncertainty" stamped over it

“Uncertainty.” If you’ve been following this blog (or any other information sources) for information on a winter storm forecast for Christmas Eve, you’re probably growing weary of that word.

But “uncertainty” remains the key word, because the low pressure system that will be responsible for the storm is just beginning to form in the area of the Gulf of Mexico this morning.

Currently, that low pressure system is forecast to move straight up through Indiana. Most of the snowfall will be to the west of the low. That means if the low goes right over you, you won’t get as much snow as you will if it goes east of you.

Meteorologists use a suite of computer forecast models to predict things like where that low pressure system will go. Different models calculate things differently, so meteorologists don’t rely on a single model, they look at several. Agreement between the outputs of several models helps them forecast confidently.

Unfortunately, as of this morning, the range of storm tracks provided by those models “remains a bit wider than one would like to see at this time,” writes meteorologist Sam Lashely in an “Area Forecast Discussion” that the northern Indiana National Weather Service office issued.

Lashley continues, “The details with where any accumulating snowfall will develop remain in question,” and “we continue to stress the uncertainty and need for people traveling to continue monitoring forecasts and remain aware.”

NWS Northern Indiana takes stab at accumulation forecast

Preliinary snow forecast map

The northern Indiana office of the National Weather Service sent an email message to emergency managers in its forecast area this afternoon that included a map (above) showing a very preliminary snow accumulation forecast for the coming winter storm.

The NWS wrote:

  • Rain is expected to change to snow from west to east across the area Wednesday evening.
  • Snow accumulations of one to three inches along with slick roads are possible from this system.
  • Confidence in the snow accumulation forecast is low at this time, but since the snowfall could impact the busy Christmas Eve traveling period, the NWS wanted to make sure emergency managers are aware of the potential.