Thunderstorms in the Forecast

spiderweb

spiderweb

Final Approach
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Ben
It is summer and thunderstorms are in the forecast every single day. I've dealt with this for the past five years, but I always value the thoughts of those with more experience than I have, especially those from the Mid-Atlantic. I'm always able either to see and avoid buildups or to get expert help when in the clouds around here.

So here is the plan: a cross country from FDK-OXB (about 130 nm) for a short weekend getaway. They are predicting SCT TS, some severe (which is pretty normal for this time of year). I would come back a few days later. I can be flexible with the time; so, for example, I can leave an hour earlier or a few hours later if it gives us a better shot. I am very familiar with the area; most MEAs are quite low, and there are many airports I could land at if there is trouble. The earliest I have the plane is 12 noon.

My current thinking is to be ready to go at noon, but wait as needed. After takeoff, remain visual as much as possible, and ask for vectors if I get into IMC. Be ready to land as needed.

My question is this: if I am allowing a good 4 or 5 hour window for launch, is it reasonable to expect that I will be able to complete the flight? I've cancelled some flights when I had no flexibility, but noticed that if I could have waited a few hours, I would have been perfectly fine to go.

Thank you in advance.
 
Ben,

1. Go over; do not go underneath the clouds if you supsect (or expect) thunderstorms in the area. Underneath a solid overcast every cloud looks like any other cloud until you see the lightening hit you or the hail starts pinging off the leading edges. Furthermore, in the usual summer haze underneath with visibility less than 5 sm you can't even see the rain shafts from great enough distance to stay 20 miles away from the boomers. OTOH, on top the visibility will be markedly better, you can tell the generic cloud from a CB by the height, etc., etc.

2. For a flight of ~100-150 nm simply look at the weather radar on the web before departing, pick a clean shot, and then confirm that it remains clear by contacting FSS frequently for weather radar updates. Do not ever trust ATC radar to keep you out of weather. Use ATC weather advice in a pinch, but kick yourself for getting to that level of desperation.
 
Don't know how it is in your part of the country, but down here in MS when there are air mass thunderstorms in the forecast I try to fly before 10am or after 5pm to avoid the peak daytime heating that makes the convective activity so troublesome. I try to stay in VMC when there are towering Cu's and ATC has always allowed my requests for deviation, because everyone else is asking for the same thing. When you can watch them boiling up it's pretty much guaranteed to be rough as a cob inside them.
 
wangmyers said:
So here is the plan: a cross country from FDK-OXB (about 130 nm) for a short weekend getaway. They are predicting SCT TS, some severe (which is pretty normal for this time of year). I would come back a few days later. I can be flexible with the time; so, for example, I can leave an hour earlier or a few hours later if it gives us a better shot. I am very familiar with the area; most MEAs are quite low, and there are many airports I could land at if there is trouble. The earliest I have the plane is 12 noon.

My current thinking is to be ready to go at noon, but wait as needed. After takeoff, remain visual as much as possible, and ask for vectors if I get into IMC. Be ready to land as needed.

My question is this: if I am allowing a good 4 or 5 hour window for launch, is it reasonable to expect that I will be able to complete the flight? I've cancelled some flights when I had no flexibility, but noticed that if I could have waited a few hours, I would have been perfectly fine to go.

Thank you in advance.
Click to expand...

If the forecast holds (scattered TRW) you ought to be pretty likely to make such a trip. And 12 noon is probably a good time slot as the mid-afternoon is when they are more prevalent. Sometimes the storms persist through the night into the morning and those often fade by late morning. I don't agree with Ed's "go over" advice in all cases as (at least in the midwest) you can have airmass TRW and good visibility under the clouds. In such cases I think it's easier to circumnavigate the storms by avoiding the rainshafts.
 
If you can get high enough to see the thunderheads, much better. That may not be possible on a ~130 mile trip. So keep visual as much as you can.

As others have noted, in that area noon is probably as good as anything else. Later in the afternoon and early evening tend to be more prevelant for airmass storms. For fast moving frontal squall lines, a 4 hour window ought to be more than sufficient.

You'll be in the air an hour or so. Ed's suggestion is a good one, but be aware that a cell can pop up very quickly, and building cells will not show on radar, so make sure you get updates, and stay visual to avoid cells. If you have avoidance gear, use it to stay away from cells.
 
boy did we get some boomers last night! wow! I thought the rain was going to break a window (I doubt it could have been hail? sure sounded like it).

when it was all over it wasn't even 1 AM.
 
If you're pretty confident that you know your regional weather patterns this helps a lot. Remember the forecast is a 'forecast' and not necessarily what is actually there. Flying through the Sierras in CA there are summer forecasts for thunderstorms all the time, but not necessarily the storm itself. Of course, this comes from the Left-coast and not the right one! :)
 
lancefisher said:
If the forecast holds (scattered TRW) you ought to be pretty likely to make such a trip. And 12 noon is probably a good time slot as the mid-afternoon is when they are more prevalent. Sometimes the storms persist through the night into the morning and those often fade by late morning. I don't agree with Ed's "go over" advice in all cases as (at least in the midwest) you can have airmass TRW and good visibility under the clouds. In such cases I think it's easier to circumnavigate the storms by avoiding the rainshafts.
Click to expand...

Lance I guess it depends on the area of the country. Ed's advice is pretty on target for the humid hazy northeast and midatlantic areas.
 
Didn't fly--way, way too rainy and stormy all weekend. Drove instead. Will fly this week for practice.
 
Check this out: http://www.emc.ncep.noaa.gov/mmb/mmbpll/cent4km/v2/

It's a 36-hour, hourly forecast of convective activity for the middle and eastern US. Results are displayed graphically - you can view either precipitation or simulated Doppler at different altitudes. The computer model runs daily at 0000Z, graphics are done around 0530Z. It's still experimental but has the potential to answer questions such as Ben asked originally.

Ben - Glad you made it safely. Sorry it rained while you were at the beach.

Regards,
Joe
 
We got stuck last night on the way back from San Diego. the brief showed storms east of our route, bbut as soon as we took off, ATC had us going north to avoid T-Storms. After Palm Springs, they gave us direct to Havasu. We got within 20 miles to home, and blackness with lighning started to surround us. VERY strange weather for 11:30pm out here. We eneded up landing at Parker (P20) and catching a ride home. You just never know.
 
The earlier in the day you go, the better. Noon is much better than 3pm, 10 am is better than Noon, etc.

Many times they are REALLY isolated, and you can literally fly around them w/o a lot of difficulty. Just keep track of where you are and where the nearest suitable landing site is. If you do have to land and "wait one out" it's generally not more than an hour or two.

Your plan sounds pretty sound to me.

wangmyers said:
It is summer and thunderstorms are in the forecast every single day. I've dealt with this for the past five years, but I always value the thoughts of those with more experience than I have, especially those from the Mid-Atlantic. I'm always able either to see and avoid buildups or to get expert help when in the clouds around here.

So here is the plan: a cross country from FDK-OXB (about 130 nm) for a short weekend getaway. They are predicting SCT TS, some severe (which is pretty normal for this time of year). I would come back a few days later. I can be flexible with the time; so, for example, I can leave an hour earlier or a few hours later if it gives us a better shot. I am very familiar with the area; most MEAs are quite low, and there are many airports I could land at if there is trouble. The earliest I have the plane is 12 noon.

My current thinking is to be ready to go at noon, but wait as needed. After takeoff, remain visual as much as possible, and ask for vectors if I get into IMC. Be ready to land as needed.

My question is this: if I am allowing a good 4 or 5 hour window for launch, is it reasonable to expect that I will be able to complete the flight? I've cancelled some flights when I had no flexibility, but noticed that if I could have waited a few hours, I would have been perfectly fine to go.

Thank you in advance.
Click to expand...
 
Hmmm. . . NC Summer daily forecast: Hot, humid, afternoon thunderstorms. Lather, rinse, repeat. This is broken only by the arrival of our regularly scheduled hurricanes and tropical storms. Lather, rinse, repeat. :(

But mornings aren't all that bad! :D
 
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