Tipping the Windmill: 7-Day VFR Weather Planning

William Pete Hodges

William Pete Hodges

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I am working on a presentation to convince the FAA NWS to embrace 7-Day VFR weather planning.

I want the AWC to use existing NWS Graphical Weather data already available and apply that data to the AWC Graphical Forecast tool for Aviation platform to extend the time frame out to 7 days. I think this would be of great value to VFR pilots and I think this is long overdue. I have been using a system that works since before 2013 when I wrote an article about this in Air Facts Journal. I thought by now the FAA NWS would have applied this technique to their existing weather tools, but that is not the case. So, since it has been 10 years, I thought I would ask them to do for us.

To this end I am collecting data in the form of computer screenshots, saved as JPEG photo files, and named in a format allowing windows explorer to search the photos by time, day, date or type of data captured. These photos will be used as the basis of a PowerPoint presentation and will also be analyzed to determine VFR and non-VFR days 7-10 days in advance.

I have been applying the analyzed data into a simple yes/no spreadsheet. The idea is to show the validity of 7-day VFR weather planning over several weeks. Take a look at the attached photos of screen shots to get an idea of what the system is all about.

This takes me a fair amount of time, and pretty soon I will be busy with work and may not be able to do it every day. Would any of you on POA be able to help me with this? I need about 20-30 days of data, about 35-50 photos every day, depending on how bad or good the forecast weather is.

Please PM me if you are interested in helping with this project.

Thank you for your time to read this post.

7-day VFR cross country weather planning : Air Facts Journal

yes-no chart Tue Jan31.jpg 01-31 Folder Table of Contents.jpg yes-no chart Tue Jan31.jpg 01-31 Folder Table of Contents.jpg 01-31 0131 day01 18z Wx AWC 1pm Tue Jan31.jpg 01-31 0131 day01 18z MVFR AWC 1pm Tue Jan31.jpg 01-31 0131 day01 PoP12 Tue Jan31.jpg 01-31 0131 day01 18z Wx 1pm Tue Jan31.jpg 01-31 0205 day06 PoP12 Sun Feb5.jpg 01-31 0205 day06 18z Wx 1pm Sun Feb5.jpg 01-31 0205 day06 18z Temp 1pm Sun Feb5.jpg 01-31 0205 day06 18z DewPt 1pm Sun Feb5.jpg
 
These 4 pictures show how the cloud base can be calculated on a clear day 4 days in advance.

The formula (Temp F - DewPt F ) / .0045 = Expected Cloud Base Altitude. Extrapolating this data along our route of flight from left to right Temp = 19 24 24 21 and DewPt = 9 2 -3 2 which corresponds to Expected Cloud Base Altitudes of 2200 4900 6000 4200. Since this data is at 1PM, and part of it is 2200 feet I would log it on the Excel table as yes? yes? Encouraging, but requiring further study.

If this information was already presented on the AWC Graphical Forcast tool for Aviation, no mathematical analysis would be needed, and the map would show our entire route of flight with our flight plan and likely indicate MVFR near Detroit and good VFR everywhere else.

This is what I am asking the AWC to do for us.

01-31 0204 day05 PoP12 Sat Feb4.jpg 01-31 0204 day05 18z Wx 1pm Sat Feb4.jpg 01-31 0204 day05 18z Temp 1pm Sat Feb4.jpg 01-31 0204 day05 18z DewPt 1pm Sat Feb4.jpg
 
Hm. Weather forecasting's gotten a lot better since I was a kid, and even in the last 20 years, but on the major commercial weather sites (Weather Underground, Accuweather, etc.) I still see huge variations between the 7-day-out forecasts and what ends up actually happening when that day arrives (I'm primarily paying attention to precipitation quantity/intensity). What data do you have access to that they don't that makes you expect better results?
 
>>>> What data do you have access to that they don't that makes you expect better results? >>>>

I don't have anything different than they do, but I do have a history of using that information to my advantage. If you are only looking for VFR weather, the main thing is to identify bad weather days first. If it looks like there will be precipitation and storms in the days ahead, then those days are obviously not going to be good VFR weather days. Keep eliminating bad VFR days until you see a day or two when the projected weather is promising. If you know ahead of time that you can't depart and return from a trip on the days that suit you, then wait until it is likely that you can.

It is my experience the forecasted weather is usually right, but not always right on time. If you know 2 days of good weather is projected 3 days from today, that weather window will likely come but it may be a day early or a day late. If you can be flexible with your schedule, then you can complete your trip during the days when the good weather is available. What you are trying to do is avoid the bad weather days and adjust your schedule so that the good weather days will be available during your proposed time frame.

For me, the primary object is to identify promising good weather days that can correspond to both the outbound trip day and return trip day. It is ok to be at my destination for 3-4 days of bad weather if I have an idea that the good weather will be coming soon. The best tool to do that would be the AWC Graphical Forcast tool because it allows me to tailor the viewing window and show my flight plan along with the expected weather.
 
But you say you have been doing this since before 2013. After a decade, don’t you already know something about the accuracy? “Several weeks” of data won’t be sufficient; you’ll need several years of data over a variety of weather conditions, locations, and climates.
 
I only consider a 7 day forecast useful if I check updates every day. That's easy enough to do using weather.gov discussions and other products like Windy.com. Having a 7 day forecast fabricated by someone else doesn't seem particularly useful to me, and is certainly not something I would put much faith into.
 
Jim_R said:
Hm. Weather forecasting's gotten a lot better since I was a kid, and even in the last 20 years, but on the major commercial weather sites (Weather Underground, Accuweather, etc.) I still see huge variations between the 7-day-out forecasts and what ends up actually happening when that day arrives (I'm primarily paying attention to precipitation quantity/intensity). What data do you have access to that they don't that makes you expect better results?
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The changeability of 7-day forecasts just means that any plans that we make based on them must be tentative. Yes, their usefulness is limited, but having them in graphical form means that it doesn't take a big investment of time to use them.
 
Half Fast said:
But you say you have been doing this since before 2013. After a decade, don’t you already know something about the accuracy? “Several weeks” of data won’t be sufficient; you’ll need several years of data over a variety of weather conditions, locations, and climates.
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First, since you do have a lot of questions, please read the reference article:
7-day VFR cross country weather planning : Air Facts Journal

This article will answer a lot of your questions. In 2013 I wrote: "A 400nm trip from Fredericksburg, VA (EZF) to Hilton Head Island, SC (HXD) is fair game for Thanksgiving, Christmas, or Easter. In the past two years we have completed this VFR trip successfully five times. How have we done so well on such a long trip VFR when the weather is so unpredictable? We have a multi-level system and we follow it. It is not perfect but it works."

Have you ever come across something you thought was so cool, you thought everybody would figure it out? That is me with this project. I know it works because I use it several times a year. In the earlier days the AWC did not have a Graphical forecast tool like they do now. That tool has only been operational for the last 2-3 years (if memory serves). It would make the perfect platform to expand the graphical forecast for multi-day weather planning.

If I can show 30 days of predicable 7-Day VFR weather forecasting, and how to use that information to your advantage, isn't that enough to see that it is of value?

If you look at the yes-no chart there are 10 vertical columns across, one for each day from day01 to day10. These are potential flying days from day01 (today) to day10. Each row represents a date that the weather was checked for each of the 10 days. Tue Jan 31 appears 5 times in this chart. Those being Friday Jan-27 day05, Saturday Jan-28 day04, Sunday Jan-29 day03, Monday Jan-30 day02, and Tuesday Jan-31 day01. My analysis of each of those days is: no. no. Meaning that my trip from Culpeper VA to Dexter MI cannot be completed VFR in either direction on that day. It is important to note that I concluded no.no. five days ago!

Don't you think that knowing you can't fly your intended route VFR 5 days in advance is beneficial?

yes-no chart Tue Jan31.jpg
 
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Honestly more than a couple days out I think it's too complicated. What we see in forecasts, especially non-aviation 5 and 10-day forecasts are most likely conditions. The meteorologists are actually looking at it in a much more complicated way and forecasting based on most likely conditions not the range of possible ones. If you want to see this in action, in foreflight look under the TAF section in weather and see if there's a button for "forecast discussion" and you can often read the reasoning why something is in the TAF- often you'll see stuff like "chance of t-storms is low but leaving it in the TAF for now" and different mentions of what might happen in more detail than you'd see in a simple TAF.

The best way to do what you're wanting I think would be to have an AI generate a video briefing for the region(s) you're flying in and give those explanations/show possible ways in which the weather might develop. That's probably on the bleeding edge of what's technically possible right now. Even then, the farther out you get the more complicated the possibilities and I think you'll hit a point where the squishy human brain just can't hold all that conceptually. Then we're back to what most of us do now- pick some days and hope.
 
dbahn said:
I only consider a 7 day forecast useful if I check updates every day. That's easy enough to do using weather.gov discussions and other products like Windy.com. Having a 7 day forecast fabricated by someone else doesn't seem particularly useful to me, and is certainly not something I would put much faith into.
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That is why I am asking the NWS to make enhanced tools available so that we can check them ourselves everyday.
 
cowman said:
Honestly more than a couple days out I think it's too complicated. What we see in forecasts, especially non-aviation 5 and 10-day forecasts are most likely conditions. The meteorologists are actually looking at it in a much more complicated way and forecasting based on most likely conditions not the range of possible ones. If you want to see this in action, in foreflight look under the TAF section in weather and see if there's a button for "forecast discussion" and you can often read the reasoning why something is in the TAF- often you'll see stuff like "chance of t-storms is low but leaving it in the TAF for now" and different mentions of what might happen in more detail than you'd see in a simple TAF.

The best way to do what you're wanting I think would be to have an AI generate a video briefing for the region(s) you're flying in and give those explanations/show possible ways in which the weather might develop. That's probably on the bleeding edge of what's technically possible right now. Even then, the farther out you get the more complicated the possibilities and I think you'll hit a point where the squishy human brain just can't hold all that conceptually. Then we're back to what most of us do now- pick some days and hope.
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I understand what you are saying, but I respectfully disagree. I think the NWS has all the data available, but they don't have that data in the best tool for the task. I think it would be easy to apply the existing data into the Graphical Forcast for Aviation tool, and it would be relatively easy for us to use.
 
I am still looking for one or two people who can copy some JPEG screen saves for me on the days when I am busy. Anyone interested?
 
For my "long-term" planning, I tend to go to the non-aviation-specific site NWS runs. They provide a general overview of the week, and you can also find an hourly graph of expected conditions, including cloud cover and precip chances, wind speeds and directions and expected temps and dewpoints. They also put out something called the "Forecast Discussion", and there you can read which models are predicting what, and what may happen instead of what seems most likely to happen. At least in MN, the weather forecast ranged from being right on to wrong about what is going to happen within the hour.
 
@scottd is a respected weather scientist, pilot, CFII, and author on aviation weather topics.

Hopefully he will be able to comment on this thread.
 
So are you talking about weather that’s acceptable for someone who won’t fly VFR with lower than 5000 ft ceilings, or are you talking about weather that’s acceptable for someone who considers “IFR” to have an 80% chance of successful completion of a VFR cross country, or some indeterminate definition in between?
 
MauleSkinner said:
So are you talking about weather that’s acceptable for someone who won’t fly VFR with lower than 5000 ft ceilings, or are you talking about weather that’s acceptable for someone who considers “IFR” to have an 80% chance of successful completion of a VFR cross country, or some indeterminate definition in between?
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The short answer to your question is YES. If successful, We will have available to us an Aviation Graphical Weather tool that will allow us to plan VFR trips to our own personal weather preferences, and begin planning our trips from 7 days in advance. The tool will provide you with enough information to select the best days to fly the weather you want. The tool will help you find the right days when that weather is likely to occur over your intended route of travel. The tool platform and the data we want already exists within the AWC and NWS systems. All we need is for them to combine the two separate systems into one.
 
William Pete Hodges said:
I am working on a presentation to convince the FAA NWS to embrace 7-Day VFR weather planning..
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Where does the funding come from to develop this?

You’ll likely need to convince Congress more than you’ll need to convince NWS.
 
William Pete Hodges said:
The short answer to your question is YES. If successful, We will have available to us an Aviation Graphical Weather tool that will allow us to plan VFR trips to our own personal weather preferences, and begin planning our trips from 7 days in advance. The tool will provide you with enough information to select the best days to fly the weather you want. The tool will help you find the right days when that weather is likely to occur over your intended route of travel. The tool platform and the data we want already exists within the AWC and NWS systems. All we need is for them to combine the two separate systems into one.
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I have no idea what you’re looking at, I guess.
 
MauleSkinner said:
I have no idea what you’re looking at, I guess.
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Let me re-phrase that... " Do you want Mustard or Mayonnaise on your sandwich? " me: "Yes. Both please. "

TCABM said:
Where does the funding come from to develop this?

You’ll likely need to convince Congress more than you’ll need to convince NWS.
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The funding comes from Aviation Use taxes, just like it does now.

All we need is to get the right people to embrace the concept, the tool platforms already exist, so it is just a matter of nudging them to do a little work for us on our behalf.
 
Palmpilot said:
The changeability of 7-day forecasts just means that any plans that we make based on them must be tentative. Yes, their usefulness is limited, but having them in graphical form means that it doesn't take a big investment of time to use them.
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I agree completely!
 
William Pete Hodges said:
…All we need is to get the right people to embrace the concept, the tool platforms already exist, so it is just a matter of nudging them to do a little work for us on our behalf.
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So this project was written into the FAA Reauthorization Act of 2018? Or are you advocating funding gets written into the 2023 act?

Or is there a master contract already written and your proposed project is just a contract modification?
 
MauleSkinner said:
I wouldn’t expect anything from your project, then.
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I understand your sentiment. Thats why I titled the article "Tipping at Windmills... " It takes some perseverance to get the FAA (and the NWS) to make a change that could be meaningful for all of us. I do have some limited experience in this area. In June of 2008 I petitioned the FAA to add two VFR waypoints to the Washington Sectional. I call it the South-East Passage. After 911 and the Advent of the ADIZ, now the SFRA, the Dalgren Firing range basically extends the restricted zone another 11 NM south to an area with very few landmarks. My proposed waypoints allowed any GPS to be programmed with a clean flyable route between several complicated restricted airspaces with jumping off points at both ends. Twenty months later in December of 2009 the waypoints VPACE and VPAXI were added. I must have had about 75 emails to the FAA. About every three months I would reply to the thread and ask for a progress update. This would start a flurry of emails and most of the time nothing was done. But after receiving a couple of polite emails requesting progress updates, I would be handed off to someone else. Eventually I was handed off to someone who could make the ball roll. And it eventually did.

I would like to do the same sort of thing here. I know it won't be easy, but I have been waiting 10 years for them to see the light on their own. So I think it is time to start nudging them a little. If I can present the right people with a good enough argument, then not acting on our behalf would be just like getting a guilt trip from your mom for not taking out the garbage or mowing the lawn! They will have to do it or they'll look foolish! That should get us some results! Afterall, they do work for us!
 
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William Pete Hodges said:
If I can present the right people with a good enough argument,
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There’s the problem I’m seeing right there…what is your argument? You want this to be valid for a very broad range of personal minimums, but you’re not presenting a case that it can be used for any of those. 3 of the 4 points in your article are NOT about forecast products, other than to present them as so unreliable as to be almost useless, but you want them organized at a glance.
 
Windy is pretty darn good at long forecasts. It’s not perfect, but I can usually have a pretty good idea of go / no go using it 5 days out. I don’t believe 7 days is really possible. Ezwxbrief is darn good for < 3 days.
 
TCABM said:
So this project was written into the FAA Reauthorization Act of 2018? Or are you advocating funding gets written into the 2023 act?

Or is there a master contract already written and your proposed project is just a contract modification?
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I don't know if I can answer that question. I don't know the nuts and bolts of how the FAA and the NWS are internally funded, and I really don't think I need to know. I am a user of their products available to the public, I am a taxpayer, and I vote. I should be able to make suggestions to them and ask my representatives in congress to inquire as to their replies and progress. That is their job, not mine.

We as aviators have the right to access all the tools the NWS and the FAA have available, and if those tools can be made better and more productive for us, we have the right to ask them to do that. We are already paying for it. I say we might as well get our money's worth.
 
MauleSkinner said:
There’s the problem I’m seeing right there…what is your argument? You want this to be valid for a very broad range of personal minimums, but you’re not presenting a case that it can be used for any of those. 3 of the 4 points in your article are NOT about forecast products, other than to present them as so unreliable as to be almost useless, but you want them organized at a glance.
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You are correct that the article only discusses the NOAA Graphical forecast in item 4, but that item is over half of the article. The Article as presented does not have enough graphics and does not show the reader how to fully use them in detail, only that they can be used. Now that I look at it again it clearly could use some improvement. That is why I am mining data from the NOAA Graphical Forecast and from the AWC Graphical Forecast for Aviation at this time. It is my intention to create a mostly graphical narrated slide show presentation explaining how this information is currently available and can be used to predict good/bad weather over the proposed route several days in advance. The overlapping slides, when flipped through in short sequences, will show how the changing weather moves and how to extract expected cloud bases and precipitation form the data as presented. If you are intending to fly VFR from point to point, you want high enough ceilings and no precipitation.

I do have a poor quality 5-part video series on tiktok that explains how I extrapolate information for VFR weather planning, but I am hoping a narrated slide show will be a much better option. The problem I have is I recorded it on my tablet in 16x9 landscape mode, and Tiktok only shows it 9x16 protrait mode, so it is at a 90 degree angle for most viewers. I don't know how to fix it so I have left it alone.

One Miracle at a time.
 
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Palmpilot said:
I believe the phrase you're looking for is "tilting at windmills," in which "tilting" refers to the medieval sport of jousting with a lance (and of course attacking a windmill with a lance would be a futile thing to do).

https://grammarist.com/idiom/tilting-at-windmills/
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An expression that, IIRC, came from Don Quixote planning to attack windmills thinking they were evil giants swinging their massive arms. Also known as a "quixotic" effort.
 
Half Fast said:
An expression that, IIRC, came from Don Quixote planning to attack windmills thinking they were evil giants swinging their massive arms. Also known as a "quixotic" effort.
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I guess you'll have to call me the Quixote Airman!
 
If you’re seriously dedicated to this and seeming to get grass-roots understanding and support (like friends, POA, local EAA chapter) then you (or an excited designee) should move forward to convince someone at EAA or AOPA to use their channels to talk to “the man”. Joust a windmill.
 
I have already reached out to AOPA I still need to reach out to EAA but finding the right person to talk to is difficult.
 
William Pete Hodges said:
I have already reached out to AOPA I still need to reach out to EAA but finding the right person to talk to is difficult.
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You want each organization’s legislative affairs group to begin with since those are the folks that engage with the government as their job. That’s EAA Government Advocacy and AOPA’s Airports, Airspace, and Weather Advocacy department.
 
I use Foreflight, which gives about 11 days of daily weather forecasts, and it is generally terrible if you try to use it to plan a flight 7 days out. As EdFred said, they don't even come close most of the time for next day forecasts, unless you live in one of those areas that is severe clear most of the year. I use the Foreflight daily weather about a week out, but I pay attention +/- a few days to understand what may be coming up. @scottd has been mentioned, he has a good, very reasonably priced web site that gives you more weather than you could possibly consume, plus it consolidates and easily animates the weather service charts. There is no panacea, or even easy way to become proficient at weather other than to study and rely on the experts assessment to make decisions.
 
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