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What would Harvey’s staggering rain do to Lake Michigan?

Posted at 6:31 PM, Aug 29, 2017
and last updated 2017-08-29 20:18:44-04

WEST MICHIGAN — Tropical Storm Harvey has been breaking, shattering, and destroying records left and right for days! We are literally in uncharted territory and even NOAA and the National Weather Service doesn’t exactly know how to deal with it or what to expect from biblical flooding.

Harvey has now shattered the all-time tropical system rain record across the entire continental United States. Just east of Houston, Cedar Bayou has reported 51.88 inches of rain. The old record from a tropical system was 48 inches set back in 1978 across Texas from Amelia. Only Hiki in 1950 in Hawaii exceeded that with 52 inches, but frankly that may also be surpassed as Harvey continues to drop more and more rain across eastern Texas and most of Louisiana.

Today, August 29, marks the 12 year anniversary that Katrina slammed New Orleans and killed more than 1800 people with severe flooding. Katrina dropped about 6.5 trillion gallons of water, while Harvey has dropped three times as much in Texas…about 16 trillion gallons. The final tally may indeed be more than 20 trillion by the time all is said and done. That’s trillion with 12 zeros! (16,000,000,000,000)

So what if all that rain fell over the Lake Michigan basin? Well…I did the math. According to our Army Corps of Engineers, it takes 390 billion gallons of water to raise Lake Michigan just one inch. Doing the math, 16 trillion gallons of water would raise the Lake Michigan water level about 3.6 feet! I find it absolutely amazing that these tropical systems can evaporate that much moisture from the Gulf of Mexico and simply deposit it inland in the form of rain.

Like Katrina, the name Harvey will likely be discontinued and banned from the tropical list in future years. They typically retire the names that do catastrophic damage and/or create substantial loss of life.

The current location of Tropical Storm Harvey is just off-shore and can be seen with radar attached in the image below. Heavy rain is still plaguing eastern Texas. The yellow band along the coast are Tropical Storm Warnings still in effect.

Harvey is expected to make landfall early Wednesday morning (again) in southwest Louisiana, then travel up the Mississippi River Valley eventually in to Tennessee and Kentucky. That will finally bring an end to the rainfall for eastern Texas and Louisiana by Thursday/Friday. See images below.

The National Weather Service in Gaylord actually superimposed the radar image of Harvey over Michigan to give us a perspective of what it might look like in size to our state. You can see at about 500 to 600 miles across, it literally covers most of the state. That image is below and was taken at the time Harvey was still a hurricane a few days ago.

It goes without saying that since this is uncharted, record territory, the National Weather Service had to create a new (bigger) color table/legend for the amount of rain that has fallen since the previous one didn’t go high enough. Jordan Tessler put the image together below and shows the dark and light gray areas around Houston that have easily seen between 30 and 40 inches…with some locations even exceeding 50 inches…and the rain isn’t finished yet!

The economic impacts can already be felt from the closure of several Texas gas refineries. Gas spiked in Michigan on Tuesday about 25 cents per gallon.
It will likely be weeks before the flood waters over Texas recede and folks can begin to rebuild. The problem then becomes can they repair, or do they need to replace? Our thoughts and prayers continue to go out to everyone in Texas for what will likely be the worst and costliest natural disaster in the history of the United States.