how likely am I to make this vfr only flight? (Weather)

MarcoDA40

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Marco
So for my youngest sisters birthday we have decided to take her to Disney.
The plan is to depart KPGV at 0700 on Nov. 23. (1200 UTC), stop for fuel just south of Savannah then continue south to KISM and approach from the west. Arrival time should be around 1200 (1700 UTC). Weather looked good for the whole route of flight and it still sorta does. Kissimmee weather (not aviation weather) shows mostly cloudy all day and looking at ceiling and visibility imagery on fore flight it shows some clouds moving in from the southeast. It only shows me until 0700 (1200 utc) as of now and according to the images It shows a partial ceiling of 6600-12000 feet. Visibility around Jacksonville also looks iffy around that time..

The return trip will be Friday 0700 (1200 utc) and it's showing Partly cloudy . Don't have much more info on that at the moment.

I've cancelled a flight before where I wasn't sure and it turned out to be an amazingly cloudy but definitely vfr day. I would,obviously err in the side of caution but am I being paranoid?

Remember, I'm VFR only. And if it matters I will be in a G1000 Diamond Da40

Tips? Suggestions? A little help from more knowledgeable weather fellows?
Thanks!
 
Today is 20th. The weather guessers really have only a dim idea of the details of WX on the 23rd.

On the 22nd if you find yourself thinking "It will probably be alright" that is an instant no-go.
 
Doesn't sound bad. As long as you don't encounter low ceilings you're uncomfortable with sounds doable. Just plan some outs (divert airports) if you run into weather you're not comfortable flying in. I'm in Alabama and a cold front just blasted thru clearing out everything, so weather should be good the next few days in the Southeast. Your departure date a little far out yet to get an accurate picture. Just keep checking.
 
There's really no way to know for sure this far out, but right now I'm not seeing anything that would scare me.

Also, don't beat yourself up if you scrub a flight and the weather turns out to be nicer than you thought. It happens to all of us, and it doesn't mean you made the wrong call. :)
 
It's still too far out to accurately account for wx. FL can sometimes be an iffy prediction as far as weather conditions are concerned. If it stays as forecasted I'd say you'd be good to go, but that's just my 2c.
 
6600' how's that iffy?
 
And don't let your out be too far to the East, there's a huge wall called the Atlantic that way. But Savannah looks great so far and so does Orlando. I'd say 'pretty likely' but as everyone else has said, you'll know Tuesday night and Wed morning for sure. Have a great flight, I'm jealous!
 
... don't beat yourself up if you scrub a flight and the weather turns out to be nicer than you thought. It happens to all of us, and it doesn't mean you made the wrong call. :)
:yeahthat: The only possible wrong call is if you go and find out you shouldn't have. Scrubbing a flight out of caution is never a wrong call.

"There are old pilots and bold pilots ... "
 
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What will happen is the ceilings will get lower and lower. When you are flying at 1000' maybe 1500' AGL (if flat terrain) and right below the clouds (weather IN the cockpit, damn its right there!), start looking for an airport with a hotel and wait it out. Thats the way these trips sometimes go... Never really know where youre gonna end up or how long its gonna take you. Usually only a day or two wait.
 
I've canceled a few trips because the weather at the destination looked sketchy. So far it's been about 50/50. Half the time I drive, watch the cloud deck get lower and lower and the winds pick up, and I'm really glad I'm driving and not flying. Half the time it's perfect clear sunny weather the whole way.

Oddly enough the first ones (glad I'm not flying in that crap) seem to be the shorter trips, and the second group usually gives me hours and hours of perfect weather while driving. Omaha to Dallas was my favorite so far. Perfect weather all weekend long.

Anyway, look at your route and figure out all the places where you can divert and wait, or tie down and drive a rental car the rest of the way.
 
You mentioned that the site weather only goes out to Wednesday morning. That's the wrong weather info to be looking at three days out.

You need to look at Prog charts, and realize they are a "best guess" at the speed and setup of major weather systems.

Wed morning:

583372c5ca2839902f1c8245ccb0e702.png


Thu morning:

90f96da44acc4e0ccf795b07cf898e21.png


Fri morning:

aaefa50006d7f1b1dae3ced7950be318.png


Sorry about the crappy iPhone screenshots.

The general story I see from these is that there's a Low setting up to go northwest of your course line that's going to create a cold front and swing it across your course line right about the time you want to fly on Wednesday, and for the return on Friday it's going to be running perpendicular directly across your course line with no way around it.

Ground weather forecast at Kissimmee looks like they're expecting about 50% cloud cover on Wednesday night so the real question is how high those clouds are and how many breaks in clouds along the cold front you can wander through.

Heavy showers/rain could develop all along the front, or not... depending on moisture content and stability. But usually at least some precip will form along it. The big question is if it's showery or widespread. So how do we look for that?

First off, it looks at first glance like it will be one of those trips where timing affects the outcome of the rain dance. Earlier on Wednesday and even Tuesday night is better until after frontal passage and most of it has gone offshore, for that leg. Depending on how fast it moves.

For the return, it all depends on how strong the precip at the cold front is at the Florida state line. The Day 6 forecast shows the cold front south of Florida completely by Saturday morning, so Saturday is your "out" going home... you just stay another night if it sucks.

I'm always looking for the one thing that says "no go" in these analyses and I haven't hit it yet for this route and these days, so I look further.

So let's look for hints of how much precip there's likely to be...

Extended Convective Outlook is totally barren in that region for a week. So that didn't say "no go". Good. No dodging embedded thunderstorms.

MOS charts (computer generated forecasts) show blob of 1000-3000' ceilings showing up on the east coast of Florida but never a time where the entire State is covered and there wouldn't be any "outs" just by going further east toward the Gulf. Still "go" looking at that.

I'm leery of MOS but it, like most things, is good for a "big picture", usually. And it's not showing awful stuff. Not perfect though on the eastern side of Florida either, but the difference between 1000' and 3000' AGL is huge for the VFR pilot.

So in general, I'd be looking at "go" this far out and watching to see how strong that cold front behaved as it forms out to the west of you and get a feel for what it does to station reports underneath it. Low vis? Low ceilings? Or broken stuff with decent vis?

If it looks like it's being nasty, bugging out of town early on Tuesday should help. If it decides to drop ceilings at Kissimee, waiting until Saturday fixes that. If the forecast speed of the cold front holds.

Help? Hurt? You'll know more in 24 hours. And even more in another 24. And the most the day of the flight. :)

Out here cold fronts "sweep" away moisture generally behind them, so doing the western end run behind them and around them almost always works. That one of yours is a pain because it's going to lay across your entire course line, but that long and stretched out like that, there's probably going to be ways to pick a way through it -- but you might have to go 100 miles out of your way. You have to wait and see how "thick" a line it creates, mostly, and at what altitudes.
 
Your screen captures look good to me, Nate.
 
Three days out, weather forecasts are basically voodoo. Wait until at least the day before you leave to start worrying about making a go/no-go decision, and build at least one or two extra days of flexibility in at the end of the trip since you won't know what the return weather will be like before you head out.
 
Three days out, weather forecasts are basically voodoo. Wait until at least the day before you leave to start worrying about making a go/no-go decision, and build at least one or two extra days of flexibility in at the end of the trip since you won't know what the return weather will be like before you head out.

Things have gotten better the last several years and these days with some limitations the 3-5 day forecasts (e.g. MOV/MEX) are fairly accurate. Of course there are still some colossal failures there (this applies to 24 hr forecasts as well) it's common for the conditions to be close with some variation in timing (might start raining sooner, etc).

Bottom line though is that NO forecast is perfect and ANY trip of more than 50 nm should be made with the expectation that it may be necessary to RTB or land short of the planned destination.

I've been trying to promote the idea that in many cases a wx forecast by itself can't be used to make a "Go/NoGo" decision, it's necessary to factor in the inconvenience of not being able to complete the trip and balance that with the forecast. IMO using the Go/noGo perspective contributes to pilots continuing a flight into weather beyond their capability because the pre-flight decision clouds the inflight decision making. IOW, baring things like IMC for a VFR pilot or freezing precip, the pre-flight wx decision should be based on a belief that the probability of weather being sufficient to make the flight safely is compatible with the consequences of that not being the case. Then the INFLIGHT wx decision making must focus on the adequacy of the ACTUAL wx, ignoring as completely as humanly possible the aforementioned consequences as well as the forecast wx.
 
If possible I'd wait until the day before to make a decision. A lot can happen in 3 days.
 
I've canceled flights and I rarely fly VFR. Pretty much all of my flights other than recurrent training are IFR. I've canceled a few where I then drove through nice weather. o_O Typically that's thunderstorms that either dissipated quicker than forecast or never materialized as forecasted, and that's the day of the flight, not 3 days out.

For your trip there is a front moving in from the west with some rain, but not looking heavy. Current forecasts show it getting to the mid-atlantic / eastern southeast on Wednesday. It looks like it may fall apart around then. IFR I'd say it looks fine. VFR, not so sure yet, keep watching.

When are you thinking of returning? There are forecasted chances of rain in the southeast (north of Florida) again on Sunday. That's a week out, so I'm not betting on the accuracy of that. If you keep your plans flexible to come back either Saturday or Sunday it gives you a much better chance of getting back without having to stop for weather.
 
Trip is looking pretty good at this point (I looked it over for a quick flight I am making up to Charlotte from JAX). Tomorrow start watching the Skew-Ts and see what they say and make your decision
 
Thanks everyone! The flight is tomorrow morning and so far is a yes go.. I will have a look at what is expected on Friday (return day) as it looks like that cold front will clear up some forecasted lower visibility in the afternoon. Worst case scenario we wait it out till Saturday.. Wont complain about an extra vacation day

Any last minute input?
 
have fun, fly dangerously. Do some loops in a class B airspace to show them who's who. Land on Disney's closed down airstrip right next to the park. You deserve it.
 
have fun, fly dangerously. Do some loops in a class B airspace to show them who's who. Land on Disney's closed down airstrip right next to the park. You deserve it.
Not sure what your point is, if any.
 
Any last minute input?

Hmm Disney World, oh yeah, bring your wallet! ;)

Enjoy your flight. KISM is great to fly into. Forget the name, but there a business there that trains and gives rides in Warbirds. Send 'em all to Disney and go get you a Mustang check out. Oh and if you do, bring the bigger wallet. :D
 
Someone pee in your cheerios again? Geez man, he was just joking. :rolleyes:
Sounds like someone peed in yours.

I wasn't sure if he was just joking, or if he was being sarcastic.
 
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