Mt.Washington-The "Presence"

[Tip]

Not only did Mt Washingtonhave near 100mph wind gust last night and is currently experiencing -95 degree wind chills, but there was a visit from the Presence last night.

03:12 AM Wed Jan 14, 2004 EST
Over the years there have been many tales of "The Presence" here on the summit of Mount Washington. Tonight, rather then snickering at these stories, I became a believer. As we were passing food around the dinner table, we heard the tower door open, and then shut. OK, so the winds which are gusting to over 100 MPH generated enough force to open the door that always latches shut. I'll buy it. What I don't buy though, is how thirty seconds later, the "wind" turned the TV on to watch the evening news. At this time we were all stuffing our faces, and it wasn't Nin because he was watching us from the heater, while wishing he was stuffing his face. The only theory is that when the temperature drops lower then forty degrees below zero Celsius or Fahrenheit, it just becomes too much for the presence to handle, so it pays us a visit. We'll accept this though, because the presence is earning its stay. Liz and I both heard someone de-icing the tower for us... yikes!

The weather outside is unreal. Working in temperatures 73 degrees below freezing is one thing, but couple that with the wind, and it has the potential to be a dangerous experience. The wind chill value is approaching 100 degrees below zero. Please don't pay us a visit over the next few days. Conditions do not get much more extreme up here, or anywhere in the world then they are right now.

What I find most amazing about this cold air, is that not only did we break a record low for the date when we hit -41 degrees... we shattered the old record of -28 which has stood since 1941! As Tim mentioned before, you can access your wind speed data by going to this link: http://weather.noaa.gov/weather/current/KMWN.html

[Stephanie]

Where did this story come from?

[isobar]

Where did this story come from?

From here Steph: http://www.mountwashington.org/weather/index.php
I was just poking around there myself this morning. It's a really cool site, especially during extreme weather like this!

[Suzi Q]

How absolutely unreal! I think I'd skip the cold there but would love to be there for a visit from "The Presence". Gave me goose bumps. One question maybe someone can answer-how can you have freezing fog when you've got a wind at 78 mph, or whatever it was? And further more, has anyone ever experienced freezing fog? Adds a new term to my met vocab, that's for sure. Just another testament to how little in control we really are!

[senorpepr]

Well... the best guess I can give for freezing fog at Mt. Washington is simply due to it's elevation. Instead of the typical fog that one normally experiences, Mt. Washington is "in" a cloud. Being inside a cloud that drops the visibility to below 5/8mi would be considered fog. As for freezing fog... it's defined as fog (which must decrease visibility less than 5/8mi) that is below freezing. Nothing too abnormal... actually it's quite normal. Winter fog is another term for it. During freezing fog you may experience some trace icing to accumulate on cold metal surfaces. That's about it.

Now to further explain the fog, it probably confuses many when I say fog must decrease visibility less than 5/8mi. This is according to the regulations that the World Meteorology Organization rules. Say you have "fog" that is decreasing visibility to 3mi. This is officially called mist. To be honest with you, I don't know why, but I don't make the rules. So bottom line is if the report says fog... it's restricting vis <5/8mi. If it's mist, it's "fog" that restricts 5/8mi or greater.

Sorry if the whole explaination is confusing. If so, let me know and I'll try to be more in-depth.

[Winnipesaukee]

During freezing fog you may experience some trace icing to accumulate on cold metal surfaces. That's about it.

Not true. Freezing fog accumulates as rime ice and almost always amounts to a whole lot more than a trace of accumulation. There are photos on the Observatory site that show wind-driven accumulations attached to stuff out to a foot or more in length.

[senorpepr]

To piggy-back on my last reply...

the weather.com definition says freezing fog is "Used to describe the phenomena when fog is present and the air temperature is below 0°C. It is reported as FZFG in an observation and on the METAR."

Furthermore, they define fog as "A visible aggregate of minute water droplets suspended in the atmosphere at or near the surface of the earth, reducing horizontal visibility to less than 5/8 statute miles. It is created when the temperature and the dew point of the air have become the same, or nearly the same, and sufficient condensation nuclei are present. It is reported as FG in an observation and on the METAR.

Finally, weather.com defines mist as "A collection of microscopic water droplets suspended in the atmosphere. It does not reduce visibility as much as fog and is often confused with drizzle."

Air Force Manual 15-111 (Surface Weather Observations) which reflects upon the guidelines set by the WMO states...

9.2.2.1. Mist. A visible aggregate of minute water particles suspended in the atmosphere that
reduces visibility to less than 7 statute miles (9999 meters) but greater than or equal to 5/8 statute
miles (1000 meters).

9.2.2.2. Fog. A visible aggregate of minute water particles (droplets) that are based at the earth’s
surface and reduces the horizontal visibility to less than 5/8 statute miles (1000 meters). It does not
fall to the ground like drizzle.

...and for the descriptor "freezing"...

9.3.3.7. Freezing. When fog is present, and the temperature is below 0 degrees C, the descriptor
FZ will be used to describe the phenomena (FZFG). The descriptor will also be used to describe
rain (or drizzle) that falls in liquid form but freezes upon impact to form a coating of glaze ice
upon the ground and on exposed objects. See Attachment 1 for a complete definition of freezing
rain and glaze ice.

[senorpepr]

Not true. Freezing fog accumulates as rime ice and almost always amounts to a whole lot more than a trace of accumulation. There are photos on the Observatory site that show wind-driven accumulations attached to stuff out to a foot or more in length.

Actually, you're correct, but I was refering to typical calm-wind freezing fog, not the extreme cases like at Mt. Washington. However, yes, it can accumulate as rime icing... a stratoform or stable condition.

[senorpepr]

This is a picture from Mt. Washington of strong wind-blown freezing fog.


...and a picture out of the foothills of SD...



I wish I had some photos from freezing fog events in Germany and the Balkans, but there have been occasions where it did accumulate. On the flip side, there were also numorous times where only a thick frost occured after the freezing fog.

[Winnipesaukee]

Actually, you're correct, but I was referring to typical calm-wind freezing fog, not the extreme cases like at Mt. Washington. However, yes, it can accumulate as rime icing... a stratoform or stable condition.

Ok. Just for anyone curious, I can't find the photo I was looking for but this one is similar. I got to feel some rime ice when I was on top on the mountain last May. It has the neatest light fluffy feel to it.

[senorpepr]

Ok. Just for anyone curios, I can't find the photo I was looking for but this one is similar.

Ahh, yes... I remember seeing this picture. Nature's power of ice.

Here's more pictures from KMWN...





More pictures of rime icing at KMWN can be found at...
http://www.mountwashington.com/pictures/rime.html

...or just pictures in general from KMWN at...
http://www.mountwashington.com/pictures/rime.html

[isobar]

I got to feel some rime ice when I was on top on the mountain last May. It has the neatest light fluffy feel to it.

Way cool! I am wicked jealous! b8)
I've been up there a few times, but usually later in the summer. (I lived in So. NH for 16 yrs)




This is my favorite:

[Stephanie]

Thanks Donna for the link! I'll have to check it out when I get home.

Winnipesaukee & senorpepr - Thanks for the cool pictures.

I was only up on Mt. Washington once, back in 1977 in August. We took the cog railway to the top where it was in the 30's!

It's amazing how treacherous the conditions are up there year round, considering it's only (I think) 6,000 feet or so. The summits of Mt. Evans and Pike's Peak in Colorado aren't like that during the summer - it's cool and you can get some nasty t'storms pass through but their weather isn't as extreme.

[JCT777]

Those pics are incredible. Thanks senorpepr and Winnipesaukee for posting them.

[Anonymous]

Wild pics!!!!! What would freezing frog do to a person---like in dense fog sometimes you can feel the moisture---would freezing fog be like walking into ice/breathing ice?

btw, We had a forecast low of 28 and fog this past weekend but they didnt call it freezing frog guess cuz its fla and no one would know what that was

[Winnipesaukee]

Wild pics!!!!! What would freezing frog do to a person---like in dense fog sometimes you can feel the moisture---would freezing fog be like walking into ice/breathing ice?

Nah...its just like walking in fog, only if you stay out in it long enough it will begin to frost up on you.

Stephanie, just FYI, it's 6,288 feet.

[powderfreak]

Since we are on the topic of freezing fog...I've got a question regarding that...
Why whenever airport observations report moderate snow with visibilities .5mi or less they nearly always tack on freezing fog along with it. Many cases will have a few hours of light snow with variable visibilies and then as soon as they report moderate snow, freezing fog is added onto it. Also, they might be reporting light snow/mist but then it will go to moderate snow/freezing fog.

Does fog just always seem to form when snowfall picks up or something? I hope someone follows what I'm saying but I've always noticed it.

For an example, here are some obs from this morning at Grand Rapids, MI (KGRR):
9am-Light snow
10am-Snow/Freezing fog
11am-light snow/fog/mist
12pm-light snow
1pm-Snow/Freezing fog
2pm-Snow/freezing fog

Thanks for any answers.
-Scott

[Stephanie]

Wild pics!!!!! What would freezing frog do to a person---like in dense fog sometimes you can feel the moisture---would freezing fog be like walking into ice/breathing ice?

Nah...its just like walking in fog, only if you stay out in it long enough it will begin to frost up on you.

Stephanie, just FYI, it's 6,288 feet.

I knew it was somewhere around there. Thanks!

[Suzi Q]

Thanks to all for incredible pics and excellent explanation of the "freezing fog". It makes me say once again" The more I think I know, the more I realize I don't know squat!".


Silly little southern snow quail

[senorpepr]

Since we are on the topic of freezing fog...I've got a question regarding that...
Why whenever airport observations report moderate snow with visibilities .5mi or less they nearly always tack on freezing fog along with it. Many cases will have a few hours of light snow with variable visibilies and then as soon as they report moderate snow, freezing fog is added onto it. Also, they might be reporting light snow/mist but then it will go to moderate snow/freezing fog.

Does fog just always seem to form when snowfall picks up or something? I hope someone follows what I'm saying but I've always noticed it.

For an example, here are some obs from this morning at Grand Rapids, MI (KGRR):
9am-Light snow
10am-Snow/Freezing fog
11am-light snow/fog/mist
12pm-light snow
1pm-Snow/Freezing fog
2pm-Snow/freezing fog

Thanks for any answers.
-Scott

Scott,
Fog and mist is something a lot of observers... both human and automated... tack onto a lot of present weather encoding. Snow, which is usually stratiform, or stable, is the great condition for fog to form. The atmosphere is relatively calm and there's moisture. As for it being freezing fog, that's because a majority of the time when it snows, it's below freezing. With that being said, normally this "fog" isn't restricting visibility very much. Say it's a normal calm day and you have some really light fog form. It's restricting visiblity to 6mi. The observation will be encoded 6SM BR for mist. Then a strong burst of snow develops. This snow alone would restrict vis to 1/4mi or 1/4SM +SN. However, we have both snow and mist. The METAR regulations say if the visibility is <5/8mi we must say it's fog. Although it's the snow that's the major of the restrictor, we would still encode 1/4SM +SN FG. Furthermore, the current temperature is -2C. Then the fog becomes "freezing" and is then encoded 1/4SM +SN FZFG.

I hope this helps.