Lake effect snow

Any more experienced Great Lakes area pilots able to answer some questions
about lake effect snow?

1. When there are bands of lake effect snow across your path:
- how high up do they go?
- how much ice do they produce?
2. What about if the band is covering the airport? Fly the approach or
wait?

Since there are bands of lake effect snow almost continually from now
until March between here and anywhere I want to go, should I give up any
dreams of flying IFR during the winter?

--
Paul Tomblin http://xcski.com/blogs/pt/
If nothing else, I can watch my cow-orkers dodge clues in a manner
vaguely reminescent of Keanu Reeves from The Matrix
-- Justin Chandler

On Wed, 23 Nov 2005 14:38:05 +0000 (UTC), Paul Tomblin wrote:

Hey Paul,

Can't answer from "experience" but that won't stop me from trying to say my
opinion :-))

Any more experienced Great Lakes area pilots able to answer some questions
about lake effect snow?

1. When there are bands of lake effect snow across your path:
- how high up do they go?
- how much ice do they produce?

Don't know how high the tops are, but lake effect snows do produce thunder
snow, having been there done that when I lived in Ohio. It's a wild
experience on the ground, I sure wouldn't want to be inside a band of lake
effect snow. I'd imagine, it be a pretty rough ride. I think the tops go
up to 15 to 20K based on the inversion levels in the more intense bands.

I would think you would need to treat the more intense bands as if you
would a thunderstorm?

2. What about if the band is covering the airport? Fly the approach or
wait?

In the more intense bands, I'd say you would not be able to fly the
approach as the viz would be well below minimums. Ceilings I'd imagine
would be close to minimums or obscured in the more intense snow bands.

Since there are bands of lake effect snow almost continually from now
until March between here and anywhere I want to go, should I give up any
dreams of flying IFR during the winter?

Having never dealt with snow, I wonder about the safety of flying IMC in
snow in general..... Wouldn't the clouds produce some form of icing within
the snowfall if you were in IMC? I'd imagine below the cloud deck the snow
would be "relatively" harmless, but inside IMC, wouldn't the clouds be
supercooled droplets?

Allen

Snow is already frozen, so it doesn't cause icing BUT there
is also a lot of unfrozen water in the snow clouds that will
cause icing. Moderate snow will reduce vis to at or below
ILS minimums and lake effect snow can last for hours.
Tops can be very good producers of ice and it pays to have a
good report on temps aloft.

Unless you have a fully de-iced airplane certified for known
ice, fall, winter and spring in the Great Lakes region can
be tough. Mid-winter is probably easier since it is colder
and the lakes may be frozen over, stopping the lake effect.


--
James H. Macklin
ATP,CFI,A&P

"A Lieberman" wrote in message
...
| On Wed, 23 Nov 2005 14:38:05 +0000 (UTC), Paul Tomblin
wrote:
|
| Hey Paul,
|
| Can't answer from "experience" but that won't stop me from
trying to say my
| opinion :-))
|
| Any more experienced Great Lakes area pilots able to
answer some questions
| about lake effect snow?
|
| 1. When there are bands of lake effect snow across your
path:
| - how high up do they go?
| - how much ice do they produce?
|
| Don't know how high the tops are, but lake effect snows do
produce thunder
| snow, having been there done that when I lived in Ohio.
It's a wild
| experience on the ground, I sure wouldn't want to be
inside a band of lake
| effect snow. I'd imagine, it be a pretty rough ride. I
think the tops go
| up to 15 to 20K based on the inversion levels in the more
intense bands.
|
| I would think you would need to treat the more intense
bands as if you
| would a thunderstorm?
|
| 2. What about if the band is covering the airport? Fly
the approach or
| wait?
|
| In the more intense bands, I'd say you would not be able
to fly the
| approach as the viz would be well below minimums.
Ceilings I'd imagine
| would be close to minimums or obscured in the more intense
snow bands.
|
| Since there are bands of lake effect snow almost
continually from now
| until March between here and anywhere I want to go,
should I give up any
| dreams of flying IFR during the winter?
|
| Having never dealt with snow, I wonder about the safety of
flying IMC in
| snow in general..... Wouldn't the clouds produce some
form of icing within
| the snowfall if you were in IMC? I'd imagine below the
cloud deck the snow
| would be "relatively" harmless, but inside IMC, wouldn't
the clouds be
| supercooled droplets?
|
| Allen
|
|

Paul Tomblin wrote:

1. When there are bands of lake effect snow across your path:
- how high up do they go?

Based on my experience on the downwind of Lake Ontario, typically between
5,000 and 10,000.

- how much ice do they produce?

I received my instrument rating during the winter of 2002-03. Most of my
28 or so actual IMC hours during that training were in lake effect snow
during the night out of Syracuse, NY. In the bands themselves and down low
(2,000 or so), there was rarely any icing. I had asked several more
experienced pilots and they all agreed that down low and in the bands,
icing was rare since the moisture was already snow.

However, I have encountered moderate to severe icing at the tops of the
cumulus clouds making up the lake effect bands. Stay away from skimming
and bouncing along the tops.

2. What about if the band is covering the airport? Fly the approach or
wait?

Lake effect snow bands can be so heavy that the airport will be below
minimums and any airline traffic will be required to hold until conditions
improve.

If you are out practicing and have enough fuel, this is an excellent time
to practice approaches through the actual missed. However, if you are
returning with the family after a long day of flying, the answer to this
question will rest on your understanding of the weather system and the
forecast (prog charts).

If the cause of the bands are due to a fast moving low pressure system,
then most likely these bands will not be over one place for long. If, on
the other hand, the bands remain persistent due to a much slower moving
system, then either go somewhere else or attempt one approach (assuming you
are proficient) with the expectation of having to go missed.

Another strategy is to be more flexible in your departure times. Adjusting
your launch time by a couple hours on either side could mean the difference
between landing in a lake effect band or not.

Since there are bands of lake effect snow almost continually from now
until March between here and anywhere I want to go, should I give up any
dreams of flying IFR during the winter?

For me I think it is an excellent time to regain actual IMC proficiency.
Understanding the reasons for the lake effect bands, proper flight planning
(fuel, alternates), and flexibility are the keys to dealing with lake
effect snow, IMO.


--
Peter

I primarily fly from WI to MI and back, crossing the lake and landing near
Grand Rapids. Often, GRR is just on the eastern edge of the lake effect.

From my experience, the answers to your questions depend on the type of
system (if any) that is crossing the area. Right now there is a warm front
crossing LM. Broken layer around 3000, overcast above, layered to 25000.
Scattered snow and snow showers below. That warm front is providing extra
lifting action that combined with the lake moisture will make the tops
pretty high, clouds laden with moisture. These are the systems to avoid in
the winter around the lakes. Lots of ice.

There's a cold front following this warm front that will reverse the
situation in a day or so. Expect less lifting action, less moisture in the
air. My guess would be to expect lake effect snow but clouds scattered to
broken around that 3000 foot area, not too thick, say maybe 5000 foot tops,
and clear above.

What I've experienced is when the lake effect snow is not associated with a
frontal system, rather just a north west wind, the tops are low, the layer
is thin, the snow showers are scattered, no icing, and ceilings are 1000 ft
or better. The further you get away from the source, the thinner the cloud
layer becomes.

With that being said, expect the unexpected. There are no firm rules that
weather follows, especially where you have ample moisture and a difference
in temperatures such as between the lake water and the frozen tundra.

Jim


"Paul Tomblin" wrote in message
...
Any more experienced Great Lakes area pilots able to answer some questions
about lake effect snow?

1. When there are bands of lake effect snow across your path:
- how high up do they go?
- how much ice do they produce?
2. What about if the band is covering the airport? Fly the approach or
wait?

Since there are bands of lake effect snow almost continually from now
until March between here and anywhere I want to go, should I give up any
dreams of flying IFR during the winter?

--
Paul Tomblin http://xcski.com/blogs/pt/
If nothing else, I can watch my cow-orkers dodge clues in a manner
vaguely reminescent of Keanu Reeves from The Matrix
-- Justin Chandler

On Wed, 23 Nov 2005 14:38:05 +0000 (UTC),
(Paul Tomblin) wrote:

Any more experienced Great Lakes area pilots able to answer some questions
about lake effect snow?

1. When there are bands of lake effect snow across your path:
- how high up do they go?
- how much ice do they produce?
2. What about if the band is covering the airport? Fly the approach or
wait?

I am based in Chicago. With the prevaling Westerly winds, we don't
see the lake effect snow as often as the Eastern side of the Lake.

Having said that - I do make trips to Indiana and Michigan, and it is
easy to pick up icing when the wind is blowing across the warm lake.
The worst icing I have experienced was from a thin band of lake effect
weather. Flying at 4000, in well under one minute (although it seemed
like an hour), I went from IMC conditions with no ice to a frozen
windscreen and an asymetric ice load on the prop. So it is not to be
taken lightly.

Regarding #2. Most of the time the bands are just snow, so flying
through them is not a big deal. However, as another poster mentions,
the snowfall rates can be significant, reducing forward visibility to
near zero. This makes a missed approach a likely outcome.

-Nathan

Paul Tomblin wrote:
Any more experienced Great Lakes area pilots able to answer some questions
about lake effect snow?

1. When there are bands of lake effect snow across your path:
- how high up do they go?

Highly variable depending on winds, temperature, general instability. I
encountered icing downwind of Lake Erie a few years ago at 11,000 feet.
Winds at that altitude were about 60 knots if memory serves.


- how much ice do they produce?

Loads. I picked up between 1.5" and 2" in less than 20 minutes.


2. What about if the band is covering the airport? Fly the approach or
wait?

Again, probably not one answer for all situations. If I couldn't get a
recent pirep, I'd go somewhere else. And even with a recent pirep, I'd
strongly consider going somewhere else.


Since there are bands of lake effect snow almost continually from now
until March between here and anywhere I want to go, should I give up any
dreams of flying IFR during the winter?

No. When it is cold enough, less than 20F or so, the snow is typically
quite dry and won't adhere to the airframe. I have had it once build up
enough static to block radio transmissions, but that was fixed shortly
after that with a static wick kit. The main thing is to be cautious
when between 25 and 34 or thereabouts (adding a little margin for
thermometer error).


Matt

A Lieberman wrote:

On Wed, 23 Nov 2005 14:38:05 +0000 (UTC), Paul Tomblin wrote:

Hey Paul,

Can't answer from "experience" but that won't stop me from trying to say my
opinion :-))


Any more experienced Great Lakes area pilots able to answer some questions
about lake effect snow?

1. When there are bands of lake effect snow across your path:
- how high up do they go?
- how much ice do they produce?


Don't know how high the tops are, but lake effect snows do produce thunder
snow, having been there done that when I lived in Ohio. It's a wild
experience on the ground, I sure wouldn't want to be inside a band of lake
effect snow. I'd imagine, it be a pretty rough ride. I think the tops go
up to 15 to 20K based on the inversion levels in the more intense bands.

My encounters have invariably quite smooth.

Matt