Tropical Storms Can Be Devastating and Deadly

Tropical storms, and even tropical depressions, can be prolific rain makers. You don't even have to reside in coastal areas to experience their impacts.

Flooding from rainfall has been responsible for more than half of all deaths associated with tropical cyclones in the United States since the 1970's according to the National Storm Damage Center.

They also stressed that flooding from tropical cyclones can occur hundreds of miles from the coast placing communities, which would not be affected by the strongest winds, in great danger. 

Ample moisture is often available for tropical cyclones. Heavy rain can begin well ahead of the tropical system and can last well past the time of landfall.

Intense tropical cyclones, like hurricanes, are steered by winds well above the surface of the earth (about 40,000 feet) when the air pressure at the surface can be below 940 millibars .

In contrast, weaker ones, like tropical storms, are steered by winds at lower levels of the atmosphere (when the air pressure at the surface is above 1000 millibars).

At times these lower-level winds are weak and can change direction, allowing tropical storms or depressions, to slow down or even meander in an erratic track.

Since tropical cyclones can produce intense rainfall, there have been occasions where rain can persist across an area for two or three days. 

A fast-moving tropical system that is producing rainfall rates of 3 inches per hour can move past you in an hour and you have 3 inches of rain.

A slow-mover can linger for days and produce eye-popping amounts.

Needless to say,  rainfall totals in the double digits can wreak extreme havoc on a region. Rivers can rise rapidly and easily exceed flood levels by a wide margin, inundating homes and businesses and in some cases making travel impossible.

Some tropical storms have created some prolific rainfall totals. In 1978 Tropical Storm Amelia dumped a whopping 48 inches of rain on parts of central Texas, which created devastating floods. Tropical Storm Alberto produced major flooding over much of central and southwest Georgia after dumping nearly 28 inches of rain.

We are coming up on an anniversary that many residents of southeast Texas would just as soon want to forget. Beginning on June 5, 2001, Tropical Storm Allison unleashed a 5-day fury in the form of intense, persistent, devastating and deadly rain.

Allison made landfall near Freeport, Texas on June 5th and weakened rapidly to a tropical depression.

As a result, Allison wandered around eastern Texas for days before its remnants slipped back into the Gulf of Mexico. Allison, and its remnants, inundated the Houston, Texas, area with up to an incredible 40 inches of rain.

This amount is almost three-quarters of their average annual rainfall.  Impacts were eye popping and disturbing. More than 14, 000 homes were heavily damaged, with an additional 34,000 suffered minor damage.

Total damage was estimated at $9 billion (the costliest tropical cyclone that never became a hurricane in U.S. history). The death toll in Texas from Allison was 23, most of them from drowning.

(MORE: 8 Things to Know about the 2016 Atlantic Hurricane Season)

Now that the Atlantic hurricane season has begun, residents of the Gulf Coast and Atlantic Coast (and a few hundred miles inland) need to stay aware of latest developments in the tropics.

Over the Memorial Day Weekend even a seemingly innocuous tropical storm (Bonnie) dumped over 10 inches of flooding rain near Charleston, South Carolina. 

Residents of Texas, who have encountered a seeming endless barrage of rain events lately, are extremely vulnerable to heavy rain and deadly flooding from a tropical cyclone.

Florida residents, who have been relatively immune to tropical cyclones lately, need to be very aware of current conditions and forecasts throughout the season.

The National Storm Damage Center has some helpful measures to prepare you for floods or other disasters.

• Create a personal plan for evacuation
• Move important objects and papers to a safe place there they can't get damaged
• Conduct a thorough home inventory-documenting your belongings will help you file an insurance claim
• Build an emergency supply kit, see how to at www.ready.gov

MORE ON WEATHER.COM: Tropical Storm Bill Floods Texas June 2015