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Weather Graphics is your source for weather forecasting tools, software, and books.




CUSTOMER COMMENTS

"Thank you for actually penning these books. They are a wonderful review of the concepts without the excessive (but necessary) amount of math behind them. I wish they had been recommended as supplements in both my undergrad and graduate years."

— Josh Tobias, 2017

  "I have used Digital Atmosphere for quite sometime and consider it to be one of the most straightforward, comprehensive, and operationally useful programs on my server. I have found it to be invaluable for my day-to-day analyses and forecasting as well as my ongoing research. Tim is also extremely helpful and absolutely indispensable when it comes to locating scripts, the best datasets, and even professional contacts to help make any organization as productive as possible."

Chris Robbins, iWeatherNet

"The quality of your products is second to none."

— C. Brian Batey

"Thanks Tim for your quick response (we like that at FedEx) about our Professional Versions! As we're a 24/7 operation, we're look forward to augmenting our present weather system with Digital Atmosphere."

— Mel Bradley, FedEx Operations

"Wow. Your books are incredibly technical and useful. I consider myself a very amateur weather watcher and feel that I am already ahead of the curve. Thank you."

— Terry W. Taylor

"The NEXRAD support is truly awesome and easy to use – and the ‘other’ feature just really tops it off. This is about my sixth email tonight – the other five being to other spotters in the area telling them they just have to download Digital Atmosphere and give it a serious going over."

— David Cashion

"I'm really looking forward to the next phase of Digital Atmosphere Workstation. I'm sure it will be as excellent as all your other products."

— Simon Keeling
Weather Consultancy Services, UK

"I run and manage a number of festival type events and Digital Atmosphere is able to produce charts that I can use for normal weather forecasting with a fair degree of accuracy and in particular wind speed and direction that is crucial to many of events."

— Robert Connolly, GI7IVX

"The archive data arrived today. WOW! What an amazing set of data! Thanks again for all the extras that you included as well!"

— Bryan Bollman, IA

"We do run GEMPAK and all the Unidata software also, but your package has numerous advantages, the biggest being Windows."

— Anonymous

"I am very impressed with what you have done. I have already shown several people at work your site. I plan on talking to our MIC [Meteorologist In Charge] soon to see if we can get Digital Atmosphere in the office to complement/supplement AWIPS."

— Ken Simosko, NWS, Pocatello

"This new version is even better than the older version which was awesome! Your programming skills and met knowledge amaze me!"

— Chris Kincaid



Malaysia Airlines Flight 370

Meteorological and oceanographic images for the Southeast Indian Ocean


Also see:
* Main Malaysia Flight 370 page
* Analysis of a suspected contrail in South Indian Ocean (initially posted March 18)



These visible images are from METEOSAT 7 and are provided as-is. Resolution is 2 km, so these will be barely able to discern a contrail, if at all. Note that this does not mean a contrail has to be 2 km wide, but must either have very strong albedo or a strong shadow (producing sharp visual contrast). If the layer is nearly saturated it is also capable of generating a persistent cirriform layer that grows significantly.

Any contrails will look like hairlines and in most cases will only be visible against the ocean. Contrails above cloud layers are usually signified by hairline shadows, with the contrail itself invisible. North-south contrail shadows are prominent during the first hour of daylight when the slant angle of the sun diffuses the contrail across large distances. During these hours the gap between shadow and contrail may be up to 10-20 pixels (compare with the shadowing on the cirrus clouds in the southern sectors).

The downside is that much of this air mass is dry and subsident. Do not expect to find a contrail; this is just one possible avenue of last resort given the current status of the investigation and it is very possible these images will provide no definitive leads. This is just a tool of last resort.

The images use a special enhancement curve to bring out signatures in the early dawn low-light conditions. Areas of absolute darkness appear as gray. Areas of weak illumination are painted in a normal black-to-white spectrum. Areas of bright illumination are painted black again with a new grayscale starting, and since they correspond to cloud areas they will probably not have contrail signatures.

I apologize that the grid lines are not labeled; this is a limitation of the display software, but from the coordinates provided here for each grid you should be able to determine this. The images have also been projected to a rectangular grid to allow for easy measurement of latitude/longitude.





Northwest region

Latitude: S5 to S20, grid every 5 deg
Longitude: E70 to E95, grid every 5 deg

* 0000 UTC
* 0030 UTC
* 0100 UTC
* 0130 UTC
* 0200 UTC
* Animated GIF (4 MB, allow time to load)



Northeast region

Latitude: S5 to S20, grid every 5 deg
Longitude: E90 to E115, grid every 5 deg

* 0000 UTC
* 0030 UTC
* 0100 UTC
* 0130 UTC
* 0200 UTC
* Animated GIF (25 MB, allow time to load)



West region

Latitude: S20 to S35, grid every 5 deg
Longitude: E70 to E95, grid every 5 deg

* 0000 UTC
* 0030 UTC
* 0100 UTC
* 0130 UTC
* 0200 UTC
* Animated GIF (8 MB, allow time to load)



East region

Latitude: S20 to S35, grid every 5 deg
Longitude: E90 to E115, grid every 5 deg

* 0000 UTC
* 0030 UTC
* 0100 UTC
* 0130 UTC
* 0200 UTC
* Animated GIF (20 MB, allow time to load)



Southwest region

Latitude: S35 to S50, grid every 5 deg
Longitude: E70 to E95, grid every 5 deg

* 0000 UTC
* 0030 UTC
* 0100 UTC
* 0130 UTC
* 0200 UTC
* Animated GIF (11 MB, allow time to load)



Southeast region

Latitude: S35 to S50, grid every 5 deg
Longitude: E90 to E115, grid every 5 deg

* 0000 UTC
* 0030 UTC
* 0100 UTC
* 0130 UTC
* 0200 UTC
* Animated GIF (16 MB, allow time to load)




What does a contrail look like?



Contrails also occur only within a specific range of conditions: those that are cold (i.e. high) and/or humid. No radiosondes were available in the eastern Indian Ocean but we can use the one for Learmonth, WA, Australia which is nearby and fairly representative. This indicates the plane would have had to been above the FL350-390 range to be visible, depending on humidity. Any extended flight at FL450 should be fully visible.




Surface conditions and satellite sectors for 0000 UTC. The overlay of the 40° INMARSAT 3-F1 arc is shown in blue, suggesting an approximate location for the plane at 0011 UTC assuming it flew south of the Equator.






Tim Vasquez is a meteorologist and owner of Weather Graphics in Norman, Oklahoma. He served as an aviation weather forecaster in the U.S. Air Force for 10 years before moving into meteorological programming and consulting. He has written 7 forecasting textbooks to date and is a columnist for Weatherwise and IFR magazines.


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