Above the BRKN

Jaybird180

Jaybird180

Final Approach
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Jaybird180
Looked at some TAFs for my trip this evening. The goal is to depart about 7p, it's a little over an hour's flight. If we get behind schedule (a likely scenario), I'm night current so it's no biggie but I would prefer to arrive during (some) daylight for this 'envelope expansion' trip; sunset is 8:13. We may have to wait out some T-Storms before departing.

My intended cruising altitude is 4,500msl. Most of the clouds along my route are reporting BRKN 2,500 & 3,500msl with possibly another BRKN layer at 7,000 and OVC 10,000 at a few locations near the route of flight. Honestly, I had to refresh my memory about cloud clearance requirements as I usually avoid weather approaching anything like this, but I think this is a nice & safe opportunity. I am qualified for VFR only.

Route of flight is

Comments?
 
I'd keep an eye on the layers beneath you. Absent the ability to do a safe and legal descent maintaining VFR cloud clearance, you can't assume you can get down at your destination when it is reporting BKN.
 
flyingron said:
I'd keep an eye on the layers beneath you. Absent the ability to do a safe and legal descent maintaining VFR cloud clearance, you can't assume you can get down at your destination when it is reporting BKN.
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Exactly. Lately, I've seen some METAR'd scattered layers that would be a bit difficult for a VFR pilot to legally descend through.
 
BKN usually means it's gonna be tough to maintain CLOUD<--2000'--YOU--2000'-->CLOUD when coming through the layer.
 
A relatively low broken layer (as opposed to scattered) plus the prospect of getting stuck on top as the sun goes down would make me pretty uncomfortable. I like flying VFR at night but only if the forecast is confident about any clouds being well above say, 8000 feet. If tstorms delay your flight a bit and you find yourself looking for that sucker hole as the sun goes down whats the plan?
 
Ditto the above... might be a problem at any point, if you have an emergency.
 
If you look at his route, it looks like at the estimated time of landing the weather is calling for SCT015 BKN070. Given that forecast, I would be watching the weather closely, and as long as that SCT015 was a pretty solid forecast, I would go and stay under the 7000 layer. The caveat would be that I won't do VFR over the top at night unless that is very widely scattered, so if it got dark I would be in a little bit of trouble. It would also make a return trip (if you're planning one for tonight) iffy.

So for me it would all depend on the accuracy of that SCT015 layer, and I would make the go/no-go just before takeoff.
 
I looked at the weather and I would not attempt the flight VFR at night.
 
If it's truly SCT 1,500 at destination and its an on-time departure, I expect that I should be able to get down safely. We have a few days we can wait out the weather if the return trip becomes an issue and can drive back if it really comes down to that.

Again, the caveat to my statement is that I typically only fly when ceilings are high enough to not be a factor.
 
Check obstacles on your route of flight carefully and go during daylight hours.

The Latest TAF for norfolk shows broken 2500 and showers in vicinity. There are a bunch of towers going to 1500 feet near your destination, watch out for them.

The area forecast is showing broken 020 after 9pm.

Time to rally the troops and make sure they're ready to leave on time! And start taking instrument lessons :)
 
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dell30rb said:
Check obstacles on your route of flight carefully and go during daylight hours.

The Latest TAF for norfolk shows broken 2500 and showers in vicinity. There are a bunch of towers going to 1500 feet near your destination, watch out for them.

The area forecast is showing broken 020 after 9pm.

Time to rally the troops and make sure they're ready to leave on time! And start taking instrument lessons :)
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And for this reason, the trip has been postponed. It's really my fault. I awoke this morning and realized as I was getting dressed for work, 'it's Wednesday and we're supposed to leave after work'. I called the XO after making this post to discover that the troops won't make formation time because their commander did not adequately prepare them.
 
VFR between layers at night (or near night -- it will get dim early in those conditions) without an instrument rating? Not something I'd recommend, especially when there's probably not a lot of space between the layers. If you do choose to go, make darn you have plenty of big holes under you all the time, and get below at the first sign they're closing.
 
EdFred said:
BKN usually means it's gonna be tough to maintain CLOUD<--2000'--YOU--2000'-->CLOUD when coming through the layer.
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Tough to guesstimate that clearance too!

Sounds like OP made a good call.
 
Seeing that you cancelled... Good.

Between layers at night is a very dark place to be. I got to peek at a bit of that back in December when working on the Instrument with Jesse.

You know where the bottoms of that first layer are but how high are the tops? That's a likely claustrophobic tunnel that could suddenly get real tight.

Under the higher overcast how are you going to see if the scattered below you is closing up? Especially if there's no moon or the upper overcast is blocking it?

No go for me VFR. No thanks.
 
What weather phenomenon causes BRKN clouds at layers like this?
 
Ron Levy said:
VFR between layers at night (or near night -- it will get dim early in those conditions) without an instrument rating? Not something I'd recommend, especially when there's probably not a lot of space between the layers. If you do choose to go, make darn you have plenty of big holes under you all the time, and get below at the first sign they're closing.
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It's reporting 200 foot ceilings now, and the view out my window agrees. Last night the TStorms passed to the NW and moved away quickly and was gone by 5. If better prepared we could have left earlier:mad2:
 
When looking at things like this, watch trends very closely, one of them being temp-dew point spread. As you remember, broken is looking up to the first layer that meets that criteria. That could be a combination of various scattered layers. It could also hide would could quickly become an overcast layer.
You mentioned this as an envelope expansion trip, if I recall correctly. I think I might not do this if it were that stage in your flight experience. You have decent light until the end of evening civil twilight, about 1/2 hour (more or less) after actual sunset, but that can be affected by many conditions. In my opinion, the likely trends (subject to you looking at the actual weather) are not conducive to things getting "better" at this time of day. Others have given you good advice, it would seem to me. If you do something like, this, be sure to look closely at the weather "up stream" to see what it is doing and how it is matching forecasts there - that can help alert you to deterioration or improvement to watch for.
 
Changed destination for closer driving. Fun flight, although I was dodging clouds the entire time. Almost called it off for low ceilings. Waited awhile and it got better, so we launched.

Leg 2 is tomorrow, provided we have a place to stay, we'd like to go to outer banks, nc. Heard about Ococoke Island from a fellow PoA'er. We'll see how goes it!
 
Jaybird180 said:
What weather phenomenon causes BRKN clouds at layers like this?
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I can think of a number of things. In December it was actually "fog" below us and a layer above. As we went further south the fog wasn't at ground level anymore and started to break up. Then it just kinda ended.

I haven't looked at the OPs area at this particular weather setup but in the summer stable air, lots of moisture and a temperature inversion can do it in my understanding. (Scott may jump in here.) When clouds form they release latent heat which can mean above them is air that's slightly warmer and no clouds until the temperature falls again a bit further up. Then more clouds.

Other ways are fronts and different air masses stacked up. Like coastal onshore winds down low and a warm moist weather system sitting on top of that coastal layer.

I'll readily admit that I've spent a lifetime watching Colorado and Front Range weather and it's just bone dry there most of the time so that could be totally wrong. :) (Styx - "Fooling Yourself" just came on the radio. Coincidence? Ha. I await greater weather mind's thoughts.)
 
Jaybird180 said:
Comments?
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Danger Will Robinson!

Above a broken layer at night, near the coast, in the summer (basically...), under two overcast layers? How do you know how thick that 2300BRKN is gonna be? That's a "finish an hour before dark" flight for me, and that's assuming I have enough fuel to get to something "clear below 7000, >6 mi" (which, for you is like to be as far as the mountains...
 
The original scenario is questionable VFR DAY. At night it would be a real no go for sure. Good call.
 
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