The National Weather Service does important work keeping us safe and informed. No issue with that. So I am watching the local news today after some heavy rains and a few potential tornados earlier today. There was a town in PA that had some weather related damage. The local talking head says the weather service is sending investigators to the town to determine if a tornado passed through the town and is responsible for the damage. What? Why? What's the point? What are they going to do? Write a report? Send it to who? Maybe the Justice Department to arrest the storm? This seems utterly pointless. We all know the weather got bad and there was lot of wind and rain. At this point, to quote Hillary "What difference does it make?"

Have you ever written an after action report? Perhaps they are critiquing their forecasting.

I think the gathering of physical evidence after the fact is an important element in validating your prediction methods.

Not sure if serious.

The storm investigators gather evidence on the scene to determine wind speeds, track, and characteristics.

They then catalog the data for comparison with computer models and programs. This data is used to forecast patterns in future storms.

I would imagine that different entities use the NWS data to determine eligibility for emergency funding (FEMA) or liability for damage (private insurers).

quote:

Originally posted by jljones:
Not sure if serious.

The storm investigators gather evidence on the scene to determine wind speeds, track, and characteristics.

They then catalog the data for comparison with computer models and programs. This data is used to forecast patterns in future storms.

This. Weather severity prediction is extremely difficult, even now with all the infrastructure dedicated to trying to do so. Surveying damage/evidence can help determine what affect detected wind speed, amounts of rain, etc can potentially have. Weather prediction is constantly being refined and will never be truly understood or be completely accurate so every little bit helps.

quote:

I would imagine that different entities use the NWS data to determine eligibility for emergency funding (FEMA) or liability for damage (private insurers).

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Insurance is certainly one issue. Was the damage caused by wind or flooding? Improved forecasting is another issue. Studying the weather is significant in its own right. Prediction of dangerous storms saves lives.

All good points. That's why I asked. You learn new things if you keep an open mind! My question was answered thoughtfully and logically.

Someone wants to sue God...

Many, if not most, insurance policies cover tornadoes but not straight line winds. A damage assessment will determine whether it was a tornado, and how strong it was.

The categories of tornadoes are now calculated by the amount and type of damage on the ground instead of just the forcasted winds. This requires someone to go in afterwards and evaluate the damage.

quote:

Originally posted by MNSIG:
I think the gathering of physical evidence after the fact is an important element in validating your prediction methods.

It's called Science.

It's not nearly as fun as caterpillar hair, dragonflies, moss, mushrooms, newts, and toads at predicting the weather.

But about as accurate.

What difference, at this point, does it make?

Now where have I heard that before?

Yep, here in Doylestown...we got hit HARD.

Worst I’ve ever seen. Happened in seconds. Big rush up...pulled up on trees...then big rush down.

Snapped my trees like twigs...

200 year old trees in town down...dozens of them.

quote:

Originally posted by Fredward:
Many, if not most, insurance policies cover tornadoes but not straight line winds. A damage assessment will determine whether it was a tornado, and how strong it was.

^^ THIS ^^

About 15 years ago, I was living in a small town in the Upper Midwest. Big storm came through with baseball sized hail and spun off a couple tornadoes. This will be important later, the storm came out of the west and traveled east.

About 5-min from work there was an indoor driving range with the proshop constructed traditionally and the indoor driving range being an inflatable held up by fans. It was on the east side of the state highway (important later). Anyway, the driving range collapsed from the hail and wind. The huge fan was later found on the west side of the state highway.

Later, NWS “investigators” reversed the tornado designation and called it straight line winds. The indoor driving range fan was the most obvious sign they were dead wrong, but there were others with trees twisted in half and trees traveling westward.

I bet the insurance companies were happy though...

post analysis data gathering. more accurate tornado occurrence data. like an after action report. many reasons for on scene investigation. i remember first reading about fujita's scale of tornado intensity. it was a great book that also had pictures of flattened buildings, vegetation, and downbursts (aka wind shear). you have to go on scene.

 
Tornados reported could also be microbursts, with similar results in damage. The investigators determine which it was to aid future forecasting.

quote:

Why would the National Weather Service send "investigators" to the scene of a storm?

If they didn't, what else would their investigators do?

As noted by some previously, the important thing is to determine if it was a tornado, straight-line winds, or a 'microburst.' The difference between straight-line winds and a microburst is the microburst is a wind blowing straight down from above (and spreading out in all directions) vs a single, lateral direction from straight line winds.

Watch some videos of the big supercell tornadoes in Oklahoma and elsewhere. Within one large cell there can be satellite tornadoes, suction tornadoes, and the main funnel. Watch some YouTube videos of the El Reno 2013 tornado in Oklahoma if you are interested in some great examples. Plus you have the rear flanking downdrafts and in flows which I think are straight line winds that can reach 100+ mph if I remember correctly.
I mention this because you can have a mixture of damaging features from these supercells. Its fascinating stuff and the researchers have made great progress.
The NWS has made some great progress in real-time radar detection but the earth isn’t flat so they mostly see only the part of the storm well above the height of most tornadoes. Ground truth before, during, and after the storm are critical.