My Mobile Mesonet

[Greg Stumpf]

Re: Good thing I don't gamble!

Originally posted by John Diel
I should have known there would be a real-time solution to that issue. I didn't think they would have had it though in that time frame. Makes sense though, if the MM could transmit the data, then the host computer could make the calculation and display it in real-time.

Actually, the GPS vehicle motion subtraction is a rather simple algorithm, and that is done on the fly on the MM laptops. These data are available live inside each vehicle. Then, wx and location data are uploaded to server.


greg

 

[Kevin Scharfenberg]

Originally posted by Greg Stumpf+--><div class='quotetop'>QUOTE(Greg Stumpf)</div>

<!--QuoteBegin-David Drummond

...do you guys have ability to see APRS up there? I know some SKYWARN groups use it and if I remember right you can hook APRS up to a wxstation like a mesonet and broadcast that out with it.

Some of the WFOs use APRS to track spotters and grab their wx data. I'm not up-to-date on what the current NSSL technology is for broadcasting vehicle location and mobile mesonet data live to the Field Coordinator (FC) - I'm guessing a combo of satellite and/or 2-meter packet transmission. I know that the FC can see the location and wx of all vehicles overlaid on radar data (WSR-88D, SMART-R, etc).

Perhaps Scharfenberg knows more...?[/b]

I think most of the mobile teams these days are using home grown software for packet transfer over 2 meter, but I don't have any of the details.

 

[Joey Ketcham]

Just got my Oregon Scientific WM-918 weather station in today along with the software package that'll be on my laptop to continuously record and archieve the weather data.

I'll probably work on finishing my mobile mesonet up this weekend, I'm still unsure about the placement of my temp/humidity sensor. I originally thought about just mounting it towards the back back of the mobile mesonet on the metal bracket that is currently holding my old anemomenter or that or mount it on the backedge of the mast that is also holding the anemometer.

My only concern is that the high winds and rain will damage the sensor, will it or should it be ok?

 

[Chris Sokol]

It really does not matter where you mount the hydrometer so much as it matters that it is enclosed in a good radiation shield. You want zero actual water to reach the sensor.

 

[Joey Ketcham]

Thanks Chris, is there any special way to make the radiation shield or just as long as it's enclosed in one? Do you leave the ends opened or use some sort of vent?

 

[Chris Sokol]

I have the same style as the NSSL shield. It is quite large, but I did have it mounted on a passenger car previously.

[Broken External Image]:http://www.kd5ili.com/images/truck5.JPG

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Some of the parts needed include 2 drains mounted end to end (with the strainers removed), a cap, elbows and PVC pipe. I should have a detailed parts list on the receipt in my file cabinet. You also need a fan in the back to draw air through when stationary.

 

[Patrick Ware]

Great discussion

I am in the process of setting up for next season too and would appreciate it if you guys could post some schematics or links on details of how to construct a MM correctly.

I have started with a good Ham Radio with APRS and data link capabilities (Kenwood D700), traded in my sports car for a safer vehicle SUV, and would like to build a MM and get WXWorx ready for next season.

I really would like to hear again the pros & cons regarding WX stations (wireless vs. wired) and manufacturer.

I would also like it if someone could post the "essentials" necessary to equip a vehicle with to better enhance the chase.
Sometimes I believe that a handheld Kestrel 4000 may be just as helpful and useful to a beginner. The last thing I want to do is put up a bunch of equipment on my vehicle which says to everyone "Hey, look at me I'm a storm chaser". :roll:
I'm new to chasing but have been negotiating severe weather flying airliners for over 20 years. I want to study them from the ground. The downside is I can't runaway anymore in a straight line at over 500 KTS so safety and some experience with an experienced chaser would be appreciated.

Thanks in advance for the help and suggestions.

BTW, this forum has been great. I have really enjoyed reading all of your posts.

 

[David Sallee]

Re: Great discussion

Originally posted by Patrick Ware
I am in the process of setting up for next season too and would appreciate it if you guys could post some schematics or links on details of how to construct a MM correctly.

Me too.... :wink:

 

[fplowman]

removed by poster to preserve the peace..

 

[Joey Ketcham]

Fplowman,

In response to what you said, the Kestrel is a nice unit to have but I think it’s better used for hikers and campers and whatnot. I own one, and I really don’t use it much because either it’s raining and I don’t want to get soaked or the inside of my car soaked to simply to a measurement.

One of the reasons I want one is because I wanted a system that will achieve the weather conditions in and around the storm, when I’m within viewing distances of a tornado simply put – I’m not going to want to sit there holding up a Kestrel to get measurements.

So once your chase is done you can go back and look at the achieved logs and use that info on many levels, who knows perhaps you, could even submit those logs to NSSL or local NWS for their purpose as well as share the data with the chase community.

Also something that Greg pointed out, the inspeed anemometer may not be correct due to the wind flow along the car – similar to the wind tunnel affect. Here’s a reprint of what Greg said:

The placement of your anemometer won't work. It is way too close to the vehicle chassis to get an accurate reading. You will be measuring air speed within the compressed airflow about the car - even if the vehicle is stationary (just think \"wind tunnel\"). In most situations, your measured wind speed will be an overestimate of the true wind.

NSSL engineers obtained information about the windflow about the vehicles that they mounted the mobile mesonets on. They found that the wind equipment had to be mounted pretty far away from the chassis in order to be effectively out of the vehicle airflow envelope. In later designs, this was about 3 feet high and 2 feet forward of the top side of the windshield.

So if the same applies to the inspeed, wind speed readings will not be accurate. So that's why chasers have the design that they do is to get the anemometer out of that wind flow for a accurate reading.

 

[fplowman]

Your right in many aspects Joey,

I was just replying to Pat as he said exactly what i was thinking when i followed your thread since its inception..
Again i didnt want to poke fun.. I was just playing somewhat of devils advocate.. Maybe someday i will see a need for a mobile Mesonet.. Otherwise.. The temperature barometric pressure and all that is recordeed and available through your internet apps for the area in my deduction.. Rain dont really bother me as a chaser.. goes with the territory and If theres a tornado?/ ill be busy punching or filming I would honestly like to find a need for one cause they are neato.. Jut not practical or helpful i believe for me at this time..
My 2cents.. No offense joey :wink:

 

[Dan Robinson]

I have an Inspeed mounted on PVC extending two feet higher than my truck's cab and six inches more out to the right. On calm days the readout is within +-2 MPH of my speedometer when I'm moving. When stationary, it has almost always been right on with the NWS locally observed windspeed.

Like Joey mentioned, it is beneficial to be able to get readings without standing outside in rain or lightning or otherwise diverting your attention from other tasks such as videography. Plus, the readout has maximum speed memory so you can catch the highest gust without having to hold an instrument for the duration of an event.

Some photos of my setup are on their site (I'm not paid by them to plug their product, it has just worked well for me).

I have had my anemometer mounted since October of last year, and it had seen about 25,000 miles of use, 12,000 of those Plains chasing this year. It finally developed a crack in the rotor after recording a 114MPH gust in Geary, OK on 5/29 and obviously didn't work right since. It finally broke off on I-64 near Jasper, Indiana on the way home from my last Plains chase trip. I will definately get a replacement rotor, I really am surprised at how long it held up considering what it has been through.

 

[Chris Sokol]

In reply to fplowman:

One of the many things that I have learned after 21 years of chasing is that the last thing that I would ever want to do is try to take accurate readings (or any type of readings, for that matter) in the core of a severe thunderstorm by sticking my hand out the window and trying to read the display of a handheld unit. Not to mention that the handheld units are very limited in comparison to full weather stations.

There is absolutely no reason to start this BS again...chase with as much or as little gear as you want, and leave everybody else the hell alone. It is none of anybody's business what any chaser either uses or equips their vehicle with. End of discussion.

You asked why would you "want to put that bohemoth" on your car. Well, the answer is extremely simple...if you do not want to, then don't. Nobody has told you that you need one, or that you have to have one. And you are also right about it being a hobby. And as with any hobby, different people are interested in different aspects of the hobby.

So in closing...you use what you want, I will use what I want, and have a nice day.

 

[fplowman]

wooooah.. pissed someone off not my intention... im new here and I had no idea this was a touchy subject..

On a lighter note I have an indian weather rock it suspends from a tripod.. It is wet when it rains and it rocks and blows with the wind when its windy.. it warms when its hot and is very cool to the touch in the cool air.. i might place one on my vehicle..

i didnt imply to drive down the road with my arm out the window and a $200 kestral.. Im on the storm at that time and i thought this mesonet tool was to help intercept?? Im unsure.. Sorry i pissed you off.. i thought i was being nice.. and i prefaced it with that.. i guess i am somewhat cantankerous.. oh and the moderator to the board just ripped my ass.. so my day is screwed up already.. 12:03 am here.. so much for the wishes of a nice day.. :?

 

[fplowman]

Chris.. i did go back and read what it is that i said that pissed you off.. i can appreciate i guess that someone would of taken that as mean spirited .. i didnt mean it that way though.. my appologies

Just went to your website and seen you sell weather units.. no wonder i pissed you off no harm dude..