VFR and scattered T-storms

cowman

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Been seeing lots of mostly VFR days in an area I'm trying to fly into where there are isolate/scattered storms around. Could have made the flight probably 2 or 3 times already if I was a little more willing to head out and be ready to land early or go around the cells if need be.

How do you develop personal minimums go/no go decisions for this? Say you're making a ~300mi flight that's expected to take just over 2.5hrs. Skies are clear all the way to the destination now but there are a bunch of scattered cells on the radar about 40-60mi away from your destination point and moving in that general direction. Would you go and just have a safe alternate airport in mind if you can't make it to the intended point?

I was in a situation like that a couple weeks ago and ultimately canceled... the larger deciding factor was a bunch of pireps along the route showing turbulence and I didn't really need to go that day anyway. I have a stratus so I'd have radar info plus with the clear skies I thought I'd be able to see anything and turn away before it became a problem but I've never flown in those conditions before. Seemed like a safe enough plan, like I said the thought of being bounced around roughly for nearly 3 hours was probably the bigger decision factor.

But what about weather that isn't so clear? What if I've got say scattered 10,000 most of the way in then in the last >100mi or so it's scattered or broken 3000... or even 2000. Would I be able to see the storm and avoid it? Am I walking right into something that will the next accident case study? Or am I being overly cautious?

Not having any first hand experience with this, but not wanting to be grounded when scattered t-storms are in the forecast almost every day for weeks as they have been.... how do I make these decisions with a healthy safety margin?
 
Would you go and just have a safe alternate airport in mind if you can't make it to the intended point?

That's what I've done. Fly to the area and look at things before 'entering' so to speak. If I don't like what I see then I have a plan to land short and wait if it doesn't look solidly OK. In some cases I have a plan for where to go eat wherever I stop short. Even if you have to wait until the evening to go in it will still usually beat driving there.

Waiting out isolated storms is a reasonable thing to do. They move and change and die so quickly. Even lines of storms tend to move quickly - if you can, fly in behind them, land short, and wait for them to pass by your ultimate destination. After they pass it, and if it's still standing, fly on in.

Picking my way under embedded or nearly-embedded storms is doable under the right conditions - With good vis and ADS-B radar on board as long as the storms themselves are truly isolated and you can give them a nice wide berth while remaining VFR. It will be bumpy under those cumulus clouds as you fly in and out of rising and falling air.
 
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Right there with you. I talk myself out of going way more than talking myself into going!
 
When dealing with turbulence forecasts, two things matter the most - the presence of passengers on board and pireps. If I see a PIREP for moderate and the AIRMET box is huge then I'm either changing altitude (if it matters) or trying to find a different route. I've had to handle 1 hour of continuous light and frequent moderate turbulence. It sucked. Thankfully my wife had on a scop patch and didn't get sick. But it was a beat down.
 
Are they simply scattered t-storms or storms that are building as part of a front?

If they are just scattered storms and no associated front, I would typically go and monitor progression enroute and divert around them. In the Baron, I use both ADS-B and onboard radar. In the Waco, I use XM weather and ADS-B.

When dodging scattered t-storms, I will usually go VFR and stay low (avoiding heavy showers that I can see.

Now, if the storms are associated with a front, I will adjust my schedule to accommodate. I may fly toward the front with intention of landing early and wait for the front to pass before continuing on (I'll call ahead and arrange a hangar).
 
What if I've got say scattered 10,000 most of the way in then in the last >100mi or so it's scattered or broken 3000... or even 2000. Would I be able to see the storm and avoid it? Am I walking right into something that will the next accident case study? Or am I being overly cautious?

I would stay high until you get to the area of reduced ceilings - then drop down below. As long as you are legal VFR, you should be able to avoid the bad stuff, but pay attention to storm cells passing over/near the field as you approach. Nothing wrong with flying part way and stopping while you wait out the storm cell passing your intended destination.
 
FWIW, I am taking the Waco from Norfolk to Ohio (365 miles each way) for the NWC reunion next week and every day is 50% chance of scattered T-storms. I'll let you know how it goes.
 
like this?

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now granted, it wasn't a 300nm trip, but I came real close to talking myself out of this trip. ended up being a great flight and great experience. I simply asked atc for any advisories that might help me weasel my way thru, and they did!
 

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Been seeing lots of mostly VFR days in an area I'm trying to fly into where there are isolate/scattered storms around. Could have made the flight probably 2 or 3 times already if I was a little more willing to head out and be ready to land early or go around the cells if need be.

How do you develop personal minimums go/no go decisions for this? Say you're making a ~300mi flight that's expected to take just over 2.5hrs. Skies are clear all the way to the destination now but there are a bunch of scattered cells on the radar about 40-60mi away from your destination point and moving in that general direction. Would you go and just have a safe alternate airport in mind if you can't make it to the intended point?

I was in a situation like that a couple weeks ago and ultimately canceled... the larger deciding factor was a bunch of pireps along the route showing turbulence and I didn't really need to go that day anyway. I have a stratus so I'd have radar info plus with the clear skies I thought I'd be able to see anything and turn away before it became a problem but I've never flown in those conditions before. Seemed like a safe enough plan, like I said the thought of being bounced around roughly for nearly 3 hours was probably the bigger decision factor.

But what about weather that isn't so clear? What if I've got say scattered 10,000 most of the way in then in the last >100mi or so it's scattered or broken 3000... or even 2000. Would I be able to see the storm and avoid it? Am I walking right into something that will the next accident case study? Or am I being overly cautious?

Not having any first hand experience with this, but not wanting to be grounded when scattered t-storms are in the forecast almost every day for weeks as they have been.... how do I make these decisions with a healthy safety margin?

As long as the cloud bases are above 2000-2500',(which is typical for spring and summer storms) I go. I just stay underneath and watch the bottoms of the clouds and look up through the gaps to see which way the upper level winds are blowing the anvils. When I see high energy in the bases (roiling clouds or downpours) I stay upwind of those and reference the upper level winds regardless what's at the surface. I stay 25-50 miles downwind of high energy clouds if I can't get up wind of them, that's where the big hail falls, the anvil side.
 
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Faced something similar last Sunday. But they were more like scattered squalls, not thunderstorms, and not part of an organized system. I was on flight following and they were offering advisories as I went, and was easily able to dodge around the squalls. I would have put the plane down if it was part of something bigger, but scattered storms are doable if you don't mind the turbulence.

Make sure to spend some time with the charts when drawing up your flight plan. Know the terrain well. If your plan is to dodge around the cells, make sure your flight path has plenty of room to do so. Trying to dodge a squall set in a valley that you are flying into is probably a bad idea. Secondly, make sure you are aware of alternate airports along your route. You may need them!
 
Something that has boosted my own confidence tremendously has been a handheld GPS with weather depictions. I can see where the storms are (or were) and give them an appropriately wide berth. I don't try and fly between or anything like that. A good example was a flight back from Kentucky last week. There were storms approaching. Because of the GPS I had a good handle on their location and knew I could get in before they hit. Without the GPS I couldn't do that. I'll miss it when its gone.
 
Something that has boosted my own confidence tremendously has been a handheld GPS with weather depictions. I can see where the storms are (or were) and give them an appropriately wide berth. I don't try and fly between or anything like that. A good example was a flight back from Kentucky last week. There were storms approaching. Because of the GPS I had a good handle on their location and knew I could get in before they hit. Without the GPS I couldn't do that. I'll miss it when its gone.

Yep, the ground based radar pics, especial the in motion ones, are great for strategic planning when you're still a ways out and are trying to figure out which general area is going to be better than the other. It can save a lot of time and fuel if you guess wrong and have to make a 100 mile or more lateral deviation.

The only way I punch through IMC though is with onboard radar, otherwise I stay in the clear, even if I'm filed IFR. Not once have I asked to make a deviation to remain in the clear and not get it.
 
Something that has boosted my own confidence tremendously has been a handheld GPS with weather depictions. I can see where the storms are (or were) and give them an appropriately wide berth. I don't try and fly between or anything like that. A good example was a flight back from Kentucky last week. There were storms approaching. Because of the GPS I had a good handle on their location and knew I could get in before they hit. Without the GPS I couldn't do that. I'll miss it when its gone.
When it's gone? I thought you were going the iPad route!

Also, keep in mind that ADS-B and Sirius can both be 5 - 20 minutes old. (Even when the data was just downloaded, so it says it was updated seconds ago, the radar sweeps took place 5 minutes ago). A storm can come up in 10-15 minutes, and doesn't show up on radar in the building stage, because there's no precip. That's why the Mark 1 eyeball is the best avoidance strategy!
 
I have a stratus and it's great but just FYI to anyone considering one or planning to rely on it in this situation, I've found that at least in WI/IL where I fly the most I don't have a reliable signal below around 3000' or so.
 
I would link you to my flight today from Louisville area to Atlanta to give you an idea of what is necessary to get the job done, but I'd prefer to keep it private. What a mess. Big storms at our departure and big storms at our destination.

Anyway, the best thing for you to do would be to go up with someone who has a bit more experience (not a 300-hour CFI) in dealing with real world storms. You can learn a lot from a short flight.

You could also go up with a buddy who is in the same boat as you experience-wise and that way you can observe, analyze, and make decisions together. This builds confidence as well as expands both of your personal minimums.

Also, don't be so strict on your diversion airports. There are thousands of public use airports at your disposal. Utilize what you need. Storms build and move quickly. You have to be flexible.
 
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I went through cells similar to the picture above when flying my airplane from Indianapolis to Maryland with my CFI. He's a long time CFI, too.

There were two portions where I felt small updrafts and had to put forward pressure or adjust trim but not too bad. Closer to West Virginia there was a point that we almost landed and waited for it to pass but there was a clearing off to the south.

We went through small patches of rain. I still think that would be about the most I would ever venture to fly around on the fringe. It looked very minor on radar but there were a few strong patches of rain but you could still see through it.
 
like this?

attachment.php


now granted, it wasn't a 300nm trip, but I came real close to talking myself out of this trip. ended up being a great flight and great experience. I simply asked atc for any advisories that might help me weasel my way thru, and they did!

This!

I have found that working with ATC is very helpful for this. I try to look at the big picture before I go to make sure I'm not heading straight into a line of storms. My biggest fear is getting surrounded. If there is a front coming, I let it pass before messing around anywhere near storms.
 
I also have a stratus 2 but at times it can take up to 2 hours to download the radar imagery (was at 9,000ft) so I wouldnt depend on it. Nexrad has a better picture but I've seen it up to 45 minutes old so be careful. Me personally I ask for deviations and just go around the darker looking clouds and that's worked so far for me.
 
I would link you to my flight today from Louisville area to Atlanta to give you an idea of what is necessary to get the job done, but I'd prefer to keep it private. What a mess. Big storms at our departure and big storms at our destination.

Anyway, the best thing for you to do would be to go up with someone who has a bit more experience (not a 300-hour CFI) in dealing with real world storms. You can learn a lot from a short flight.

You could also go up with a buddy who is in the same boat as you experience-wise and that way you can observe, analyze, and make decisions together. This builds confidence as well as expands both of your personal minimums.

Also, don't be so strict on your diversion airports. There are thousands of public use airports at your disposal. Utilize what you need. Storms build and move quickly. You have to be flexible.

I flew from Cincinnati down to Georgia (and then on to Florida). Stormscope + ADS-B radar (with the delay in mind) saved the flight. The takeoff was probably the scariest I've ever had. Live and learn. I would do it again, but do a short field to pop up quicker. Once up in the air all was workable... but I did go way out of the way to avoid the convective activity.
 
Are they simply scattered t-storms or storms that are building as part of a front?

If they are just scattered storms and no associated front, I would typically go and monitor progression enroute and divert around them. In the Baron, I use both ADS-B and onboard radar. In the Waco, I use XM weather and ADS-B.

When dodging scattered t-storms, I will usually go VFR and stay low (avoiding heavy showers that I can see.

Now, if the storms are associated with a front, I will adjust my schedule to accommodate. I may fly toward the front with intention of landing early and wait for the front to pass before continuing on (I'll call ahead and arrange a hangar).

I would stay high until you get to the area of reduced ceilings - then drop down below. As long as you are legal VFR, you should be able to avoid the bad stuff, but pay attention to storm cells passing over/near the field as you approach. Nothing wrong with flying part way and stopping while you wait out the storm cell passing your intended destination.

Pretty much everything he said. I stay high as long as possible when there are no storms in the area, try to be above the cloud bases and just dodge the taller buildups. When there are scattered/isolated storms I drop down below the cloud bases to be able to see the downpours and give them a wide berth. If the cloud bases are so low that I can't maintain sufficient altitude above terrain/obstructions, I'm landing. Likewise if the storms get to be too numerous and I can't get around them, I'll also land. Usually when I divert left or right I do it based on which way takes me (a) away from the direction the cell is moving but also (b) toward the friendliest terrain/alternates if things close in and I need to land. Those don't always agree, so (a) usually wins out.
 
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I would add that you need to have the discipline to stop short and wait it out vice push ahead and try to get in to your destination just before the storm. The people that get themselves killed are typically the ones who try to beat the storm to the runway.

Nothing wrong with flying 270 miles and then waiting a couple hours to fly the last 30.
 
The distinction between scattered and large, frontal system storms is a BIG deal. I fly with an ADS-B receiver and get near real-time weather with NEXRAD radar images on my tablet. That gives me the big picture. I use the NEXRAD weather to tell me whether the storm I'm looking at has a limited depth, or if it is the pointy end of a frontal system that continues indefinitely along my route of flight. I use my eyes to give me the here and now part of the feedback needed to safely fly around isolated cells. When flying around isolated thunder cells, I continually assess the availability of broad escape paths should I decide to abandon my flight. One thing to be very aware of is that the turbulence from a thunderhead isn't limited to the area directly below the cloud. Give yourself a wide gap from any thunder boomers. Turbulence can extend a considerable distance from the clouds.

The link below takes you to a video of my flight to Triple Tree Aerodrome in S.C. last year. The flight home required dodging lots of isolated cells, and it was very doable.

On the other hand, I was flying from Santa Fe, NM to Virginia by way of Norman, OK one summer and a long frontal line of thunderstorms made me divert all the way to North Platte, NE to get around the northern edge. You don't want to tangle with thunderstorms, but there is no reason to avoid flying all together when isolated storms forecast along your route of flight. This country is blessed with a plethora of airports, and there is always a place you can divert to when needed if you make your decisions early enough.

https://www.youtube.com/watch?v=Gaexj33sK4s
 
I also have a stratus 2 but at times it can take up to 2 hours to download the radar imagery (was at 9,000ft) so I wouldnt depend on it. Nexrad has a better picture but I've seen it up to 45 minutes old so be careful. Me personally I ask for deviations and just go around the darker looking clouds and that's worked so far for me.

Two hours is pretty abnormal for ADS-B radar depictions in my experience. I've never seen the downloads take much more than a few minutes and the actual radar depictions have always been very close to real time in my (relatively recent) experience.
 
I would add that you need to have the discipline to stop short and wait it out vice push ahead and try to get in to your destination just before the storm. The people that get themselves killed are typically the ones who try to beat the storm to the runway.

Nothing wrong with flying 270 miles and then waiting a couple hours to fly the last 30.

Yep, I've used that method many times, especially west bound. Fly up to the front, find an airport to land, ask for a hangar, go have lunch and watch some TV, launch again after the front passed. No worries.
 
Been seeing lots of mostly VFR days in an area I'm trying to fly into where there are isolate/scattered storms around. Could have made the flight probably 2 or 3 times already if I was a little more willing to head out and be ready to land early or go around the cells if need be.



How do you develop personal minimums go/no go decisions for this? Say you're making a ~300mi flight that's expected to take just over 2.5hrs. Skies are clear all the way to the destination now but there are a bunch of scattered cells on the radar about 40-60mi away from your destination point and moving in that general direction. Would you go and just have a safe alternate airport in mind if you can't make it to the intended point?



I was in a situation like that a couple weeks ago and ultimately canceled... the larger deciding factor was a bunch of pireps along the route showing turbulence and I didn't really need to go that day anyway. I have a stratus so I'd have radar info plus with the clear skies I thought I'd be able to see anything and turn away before it became a problem but I've never flown in those conditions before. Seemed like a safe enough plan, like I said the thought of being bounced around roughly for nearly 3 hours was probably the bigger decision factor.



But what about weather that isn't so clear? What if I've got say scattered 10,000 most of the way in then in the last >100mi or so it's scattered or broken 3000... or even 2000. Would I be able to see the storm and avoid it? Am I walking right into something that will the next accident case study? Or am I being overly cautious?



Not having any first hand experience with this, but not wanting to be grounded when scattered t-storms are in the forecast almost every day for weeks as they have been.... how do I make these decisions with a healthy safety margin?


There are a few tools out there that can answer your questions pertaining to predicting potential weather. I would learn to read the skew-ts and understand CAPE. As well the Lockheed Martin site has a lift index / k factor chart that helps show thunderstorm potential. There is also the CCFP chart.

ADS-B weather can help you keep track of newly developed storms but be cautious of the delay. If you want more comfort in storm detection, consider adding a StormScope. I flew for years with a WX-8. It worked but was a bit rough in helping figure out how much of margin to give an emerging storm. I recently upgraded to a Wx-500 and the newer spheric detection instruments really help define the area of concern. Here is an example of a storm way out in front of me:

36282852ddcca529999658819fb31344.jpg


The StormScope showing the activity in front of me but off to my left a little bit. The stuff out at 234 nm is out of range, but what the StormScope is starting to show is the emerging activity of the storm just south of the course line (has a single lightning bolt on it).

b289ec3eed018dd479f1c52292ac1a7f.jpg


The GTN showing the approaching storm:
353c791af57c002adbefb7981a8654be.jpg


The hard part of summer time pop up storms is how fast they can form. The ideal tools would be onboard weather radar (and knowing how to use it) combined with a StormScope.







Sent from my iPad using Tapatalk
 
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isolated.jpg

Yep. Just another day in Texas. FIS-B has been a great improvement for me in this regard. I've been quite satisfied with the update rate between what I see outside and what FIS-B was giving me. I use a skyradar puck. It's a real shame these third party devices are not as widely supported by the EFB apps, especially the android ones. Since I'm not a fan of apple and the ipad, my options are even more limited in that regard.
 
What the heck is going on with the weather in the Northeast? I have never seen this many thunderstorms.

96c29efa0e20220ad6e4e8d79ffda973.jpg



Sent from my iPad using Tapatalk
 
WARNING: Necro post!!!

I'm finding myself in the same situation. Just passed 150 hours and I fly generally in very good weather only. @cowman I'm curious if you've tested the waters more over the past 2 years, especially in our area. I'm not far from your location and want to make a trip to Danville (IL) on Friday morning. I prefer the 45 minute flight over the 2+ hour drive. Clouds are forecast to be nice and high but there is a chance of an afternoon storm. I'm trying to learn to read CAPE index numbers. Just curious if you have an update on your situation from this thread. CAPE forecast looks fairly benign at the time I want to head home but it leaves it open to a chance. Front would be to the south.

cape forecast.jpg
 
I just peeked into my logbook to see what the heck I was doing that day. Figured it out... that was when I was moving from my old home back in WI down to my new airplane home at KUIN Quincy, IL. I had been fighting with schedules/weather trying to get my airplane moved and couldn't get a window to get it done. I finally made the flight 3 days after this post.

There were thunderstorms down by St Louis that day which were my primary concern but never became a factor. What did become a factor were ceilings.... all of which were forecast to be more than sufficiently high or clear by later in the morning and METARS stations all along the route were reporting high ceilings, clear skies, or what I(incorrectly) interpreted as early morning fog. The end result was I made the flight but instead of cruising at nice high comfy altitudes I was constantly ducking down to one point where I found myself at pattern altitude around Keokuk calling each airport's CTAF to report my location as I came through and resolving to land the airplane if it got the slightest bit worse. By that time I was in range of my destination's ASOS and it was reporting a much higher ceiling.... and "distant" thunderstorms to the south with me coming from the north. I finished the flight without any serious incident but those aren't conditions I'd want to have intentionally flown into. My main mistake was an assumption that the few low ceilings I saw before taking off were early morning fog that was going to burn off and believing the TAFs saying it should already be clear.

But you were asking about scattered T-storms not ceilings.
Yes, I have flown more in conditions like this in our area. The last time I recall was last fall on a flight from K15 at the lake of the Ozarks in Mo to KBBG in Branson, MO. I'd been on my way to KBBG the evening before but ceilings were not good, it was getting dark, and I had a friend at K15 who would pick us up and drive us to a hotel/dinner so I opted to land early. Btw, my wife and I had a great meal and a good night then. The next morning, the T-storms that were supposed to have passed through in the early AM hours hadn't yet. Our route was basically clear but there was a big nasty cell just 20mi or so to the west of our course. I delayed and watched the weather for an hour or two while getting breakfast/dressed/etc. The cell was very slow moving and was tracking mostly north. The distance opened up to closer to 30mi with everything trending in our favor, ceilings were 3000+ all the way to the destination and with the winds this was a short flight ~30min. I departed and we carefully made our way to Branson. I did this with 3 different SHTF options in mind, I could turn around and go back to K15, land at a small field just off our course, or I could turn and run away from all the bad weather towards Columbia, MO- a large field with lots of services that I'd been to before. During the flight I could see distant lightning off my right wing, but it was distant- right where I expected the storm to be. We completed the flight without incident.

I do not like flying near bad weather but I'm more comfortable with it than I was 2 years back. I will only do it during the day, only when I have a significant margin of safety AND multiple options if the weather turns worse than expected. I also fly with a stratus and foreflight so I can get a current and clear weather picture... I think this is critical. Above all IMO you MUST be ready to land short of your final destination. Have some thought about where you might do that ahead of time, what kind of day/night you'll have because of that, and make sure you are mentally OK with that outcome.

Another thing I've found about midwest weather is it's common to have storms and IFR conditions all day then for everything to start clearing up after about 5pm and end up with a clear starry sky by nighttime. Some may argue with this but if I can wait for a crystal clear night flight vs dodging storms in BKN 3000 conditions during the day I will take the night option every time.

Every day is different, watch not only the forecasts but how the current conditions are changing, have alternate plans. It's about all we can do sometimes.
 
I didn't get comfortable with dealing with scattered CBs until I did several flights in those conditions with much more experienced pilot friend. That made a huge difference in confidence. This was pre-GPS (anybody remember those days? :D ).
 
Just when you think you know your limits, something like this comes along to make you rethink it all again...
Long-time pilot gets caught up in weather, resulting in a fatal crash. One wing was found almost 5 miles from the crash site. This was last week.
http://www.kathrynsreport.com/2017/04/pipistrel-virus-sw-fatal-accident.html

Yeah this stuff is what has anyone new to flying scared and so cautious that they barely end up flying(at least this was me). They should be scared too, they barely know what they're doing.

Then you fly for a few years and get more confident and you start to think you know what you're doing. Pro tip: you don't, the guys who have degrees and doctorates in meteorology don't even know for sure. If you get it wrong enough you die. Leave lots and lots of room for error. You need 2,000' ceilings? Well sometimes the weather between ASOS stations is different or sometimes the stations are reporting incorrectly, get 3,000 before you leave. Storms nearby? Where are they going? Think you're good with a 20nm buffer? Wait till you have 30. Allow yourself a safety margin and then add in an error margin too.... be willing to land and wait for tomorrow.

Some folks will tell you that if you're ever in doubt that you shouldn't go... but a new pilot ought to ALWAYS be in doubt. Heck an old pilot ought to always be even more in doubt because they're not as scared anymore. You know at some point you'll need to get somewhere or realize that you didn't buy an airplane or get all this training to sit at home watching airplanes on youtube. Just leave yourself a safety margin then add in an error margin and have yourself multiple plans of escape. At some point we have to fly after all.... just never forget that statistically speaking VFR into IMC is what is most likely to get you killed.
 
new pilot ought to ALWAYS be in doubt

<----------- This guy.

Stretched my wings a bit a few weeks ago flying in MVFR over a longer distance than I had done before. Bumps weren't fun but it all worked out. Ceilings never collapsed on me but I was watching like a hawk and looking for places to go. Been through non-convective rain and ATC helped me stay away from big cells. Done snow too. Next step is figuring out storm dodging comfort.
 
Been seeing lots of mostly VFR days in an area I'm trying to fly into where there are isolate/scattered storms around. Could have made the flight probably 2 or 3 times already if I was a little more willing to head out and be ready to land early or go around the cells if need be.

How do you develop personal minimums go/no go decisions for this? Say you're making a ~300mi flight that's expected to take just over 2.5hrs. Skies are clear all the way to the destination now but there are a bunch of scattered cells on the radar about 40-60mi away from your destination point and moving in that general direction. Would you go and just have a safe alternate airport in mind if you can't make it to the intended point?

I was in a situation like that a couple weeks ago and ultimately canceled... the larger deciding factor was a bunch of pireps along the route showing turbulence and I didn't really need to go that day anyway. I have a stratus so I'd have radar info plus with the clear skies I thought I'd be able to see anything and turn away before it became a problem but I've never flown in those conditions before. Seemed like a safe enough plan, like I said the thought of being bounced around roughly for nearly 3 hours was probably the bigger decision factor.

But what about weather that isn't so clear? What if I've got say scattered 10,000 most of the way in then in the last >100mi or so it's scattered or broken 3000... or even 2000. Would I be able to see the storm and avoid it? Am I walking right into something that will the next accident case study? Or am I being overly cautious?

Not having any first hand experience with this, but not wanting to be grounded when scattered t-storms are in the forecast almost every day for weeks as they have been.... how do I make these decisions with a healthy safety margin?


Learn to love the Skew-T. Go to youTube and watch "Weather in the Vertical" by CFII/physicist Ed Williams. Note that in the upper right corner of each chart there is a number shown as CAPE...that is a measure of instability:

http://www.spc.noaa.gov/exper/mesoanalysis/help/begin.html

There are convectivity charts available from www.aviationweather.gov/GFA. Study the information and roll the dice.

Bob

Bob
 
Are they simply scattered t-storms or storms that are building as part of a front?

If they are just scattered storms and no associated front, I would typically go and monitor progression enroute and divert around them. In the Baron, I use both ADS-B and onboard radar. In the Waco, I use XM weather and ADS-B.

When dodging scattered t-storms, I will usually go VFR and stay low (avoiding heavy showers that I can see.

Now, if the storms are associated with a front, I will adjust my schedule to accommodate. I may fly toward the front with intention of landing early and wait for the front to pass before continuing on (I'll call ahead and arrange a hangar).

That, just remember the lag time with ADSM/XM/NEXRAD can almost turn it into "fake news"

I also like to make sure I have airports long the way that I can land (and hangar) at if needed.

Eyes outside, staying below, that's the safest way to deal with convective activity
 
I've driven up to the line then backtracked to the nearest airport and took cover. Hour later I'm airborne and flying out behind it. This particular instance I recall a bloke mowing the grass help me get the airplane under a roof. It stormed like crazy for a while so I was happy it was not outside.
 
Another time we were caught between two lines and I could not get to where I wanted to go but still had ample room to backtrack. Landed and called the airport manager who says all hangars are full so tied it down, locked all the doors, and we drove the courtesy van home. Storm catches up with as we drive away, It rained, hailed, and blew so hard on the way home I was sick to my stomach and I just knew the plane was trashed.

Drove the van back the next day and found the airplane had moved a little from the wind. Could NOT find a hail ding anywhere but boy was the carpet wet inside.
 
<----------- This guy.

Stretched my wings a bit a few weeks ago flying in MVFR over a longer distance than I had done before. Bumps weren't fun but it all worked out. Ceilings never collapsed on me but I was watching like a hawk and looking for places to go. Been through non-convective rain and ATC helped me stay away from big cells. Done snow too. Next step is figuring out storm dodging comfort.

Many people recommend paying up for one of the classes @scottd offers regarding reading and interpreting weather charts related to CB/visible moisture.
 
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