Hurricane Irma Live Thread Part II

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[TXnMA]

"can anyone explain the infrared vs radar?"

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Apologies for not answering your query earlier! I was busy, putting together a big archeological presentation for a meeting today...

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I'll use current imagery from both systems in Miami,FL, tonight, Saturday September 9, to illustrate the differences
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RADAR (capitalized because it's an acronym...) is basically an image generated by reflections from raindrops of radio pulses that are sent out in a circular "sweep. (Analogy: You don't actually "see: an object illuminated by a flashlight -- you see the light reflected back from that object. "RADAR "illuminates" with radio waves instead of light beams...)

As shown below, each RADAR station has a discrete limited coverage range; things beyond that range are, in essence "invisible" to that specific RADAR station. Notice that, even as Irma is approaching Miami, the "eye" is not yet within the range of Miami's RADAR. To lessen that weakness, composite images from multiple, overlaping RADAR stations are often displayed. If, for example. this display included the RADAR on Key West, the eye would be visible. Back when IRMA was over Cuba, it didn't even show up on Miami RADAR...

In IRMA's case, the value of RADAR is that can show rainfall intensity, and can give a measure of how fast those rain bands are moving horizontally. And, importantly, it can sometimes give an indication and warning of tornadoes embedded in those rain bands

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Satellite Infrared images are photos taken using the "long" (low frequency) wavelengths beyond red in the light spectrum. They are basically images of the temperature of clouds. Sometimes, they are color-coded to reflect temperature (or, more accurately, heat content) of clouds. Just as important, since they are taken by satellites far out in space, they can show weather features that are well beyond the range of land-based RADAR:

IR images are just photos of cloud tops viewed with sensors tht are receptive to heat, rather than to visible light...

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Hope this is helpful -- and not too late...! '-)

TXnMA

[FamiliarFace]

Yes, of course! Thanks for reminding me!

[jeffers]

Not a,jump, an accelleration.

Still accelerating?

Fast is good.

[huldah1776]

THANK YOU...I am a visual learner and it’s never too late to learn something new. I depended on watching the radar out in tornado alley and got pissed when the news pictured how YUUUUGE the storm was when there wasn’t even any rain on the radar at weather.com.

I learned it is the wind that THIS hurricane will be known for. Unlike the last one which was rain.

I love clouds, but not when they form that little hook at the bottom of the radar.

Archeology, eh? I bet you don’t like wind OR rain! :) I just realized that archeologists should be expert empathists and mechanics who can figure out what others did just by looking at their stuff.

Must be fun teaching others, too. Have a great day!

[Travis McGee]

I just don’t want to find my boat in somebody’s yard.

[ROCKLOBSTER]

Yes, I knew exactly what you meant, but that is the kind of “smart@$$ remark” I’d throw back in their faces.

Please feel free to use it....apply “liberally”.

[Maskot]

Checking in from st lucie county. Wind picking up, rain bands coming sporadically, flooding in fort pierce. Still have power, crossing my fingers.

These weather people are hilariously silly.

[SomeCallMeTim]

Remains to be seen just how sharp, but... I think it could be pretty quick. We MIGHT just see a “best case” scenario here.. where, Irma hits the Keys hard, but goes inland far south of Naples. That’s where the FEWEST people live. And, it would give the least time for re-development. That’s what I’m pulling for..... but, will need significant heading change to get there.

That's what I said at 6 pm yesterday. Even at midnight last night, it wasn't completely clear which way Irma was going. This morning, it looks like it could still happen. For sure, it looks like the WORST of the storm surge will go into the everglades. But, sadly... it looks like Naples is going to get a HARD hit.

The whole thing looks pretty wobbly now, and more our less adrift. BEST we can hope for is to get this center over land... They're not projecting it, but... It sure looks like it might.

People are going to get a good look at what storm surge can do. I predict, when this is all over: We're going to see a bunch of new regulations about WHERE people can build.

[TXnMA]

Yes, we most certainly do! (Physical chemist...)

[KC Burke]

As you predicted, the first tower crane has collapsed in Miami.

As I said in my first reply, these are often unable to withstand something like this wind speed.

[metmom]

:)

[metmom]

And just who is surprised?

I’m more surprised it took this long.

[KC Burke]

Since P-Chem guys are always kind of brilliant / crazy, I will post the Extreme Wind warning for Collier County of 115mph to you.

this is Marco and areas south of Naples.

[blam]

I'm less worried here in Mobile today than I was last night.

I was just a my local Lowe's building supply (15 miles west of Mobile) store and the place is swamped with people from Florida. One guy, said he was from Clearwater, bought every blue tarp and associated supplies in the store.

[blam]

For decades seismologists were unable to explain some random ‘squiggles’ on their charts....someone finally realized that they were recording tornado touch-downs.

[TexasGator]

What are you drinking?

[TexasGator]

Lol

[TXnMA]

And, until they were outlawed, sonic booms (especially when they passed over cities with tall structures and tall, forested areas -- with objects that could vibrate and couple energy into the ground) were also puzzling...

[TXnMA]

Well, you definitely got the "crazy" part right! '-)

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And, thanks for posting the warning!

As I sit here, dry, cool & serene -- 240 miles inland, atop my watershed ridge, sheltered by the dense far northeastern Texas Piney Woods -- I'll pray for the folks in Collier County, FL, and surrounding areas.

And, I'll continue to pray for the folks in my old hometown, Houston.

[blam]

"And, until they were outlawed, sonic booms (especially when they passed over cities with tall structures and tall, forested areas -- with objects that could vibrate and couple energy into the ground) were also puzzling... "

Aye.