Ice Storm? Dec 11/12, 2008

Resident 2B · 12-11-2008, 02:20 AM

It is starting to look more and more like an ice storm for the next 24 to 36 hours. Ice build up of an inch or so is possible in some areas.

Ice storms are very hard to predict, but a layer of cold air trapped at the surface under a warmer layer is what causes the ice and not sleet or snow. The snow falls through the warmer layer, melts into water at about 35 - 40 degrees F, then remains as water until it hits the ground/trees/power lines that are in the trapped layer of cold air.

If the trapped cold air layer is too thick, you get sleet, something a lot easier to deal with than ice. This is because the water has a chance to freeze before it hit the ground. Sleet is small ice pellets and it bounces when it hits the ground.

I hope it is sleet, but it is looking like ice to me right now.

R2B

CanisLupusArctos · 12-11-2008, 01:21 PM

Snow began late this morning and has accumulated 0.1" before changing over to sleet. The temperature is now 29 degrees and dropping slowly. Soon the sleet will change to freezing rain.

The National Weather Service is advising that travel be curtailed this afternoon and tonight except in an emergency. Ice accumulations of an inch are possible.

Like R2B said, ice storms are very difficult to predict because they involve layers of different-temperature air stacked on top of each other at different altitudes. It can behave the same way as the lake water mixes at various depths early in the summer - you get warm spots and cold spots and when you jump in, you never know what you're going to get.

NHKathy · 12-11-2008, 05:32 PM

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so pretty!

hope fully not too slippery or dangerous though...

Lakegeezer · 12-11-2008, 08:48 PM

That picture of Meredith (Oops! Centre Harbor - thanks Eagle) from the Mt. Washington would make a good Christmas card.

The Eagle · 12-11-2008, 11:03 PM

Hi Lake Geezer!
I am pretty sure that photo is of Center Harbor and not Meredith. Youre right, it would make a beautiful X-Mas card!
The Eagle

Resident 2B · 12-12-2008, 12:36 AM

It is raining at a fairly good rate with the temp at 28 degrees at this time here at the Weirs. The trees are getting loaded with ice. However, the rain rate is keeping the roads somewhat wet and not that icy. The highway folks are doing a great job with sand and salt on the main roads.

There are several scanner reports of power line/tree contacts with small fires and a few transformer fires. This is likely to get worse over night.

I agree with the previous posters. Great winter scene!

R2B

trfour · 12-12-2008, 12:00 PM

We even got snow here in Dallas/Fort Worth from this thing!

Story; http://www.msnbc.msn.com/id/28193030

12-11-2008, 02:20 AM	#1
Resident 2B Senior Member Join Date: Apr 2004 Location: North Shore, MA Posts: 1,358 Thanks: 995 Thanked 314 Times in 164 Posts	Ice Storm? Dec 11/12, 2008 It is starting to look more and more like an ice storm for the next 24 to 36 hours. Ice build up of an inch or so is possible in some areas. Ice storms are very hard to predict, but a layer of cold air trapped at the surface under a warmer layer is what causes the ice and not sleet or snow. The snow falls through the warmer layer, melts into water at about 35 - 40 degrees F, then remains as water until it hits the ground/trees/power lines that are in the trapped layer of cold air. If the trapped cold air layer is too thick, you get sleet, something a lot easier to deal with than ice. This is because the water has a chance to freeze before it hit the ground. Sleet is small ice pellets and it bounces when it hits the ground. I hope it is sleet, but it is looking like ice to me right now. R2B

12-11-2008, 08:48 PM	#4
Lakegeezer Senior Member Join Date: Feb 2003 Location: Moultonboro, NH Posts: 1,679 Blog Entries: 1 Thanks: 354 Thanked 640 Times in 291 Posts	Wow That picture of Meredith (Oops! Centre Harbor - thanks Eagle) from the Mt. Washington would make a good Christmas card. __________________ -lg Last edited by Lakegeezer; 12-12-2008 at 12:16 AM. Reason: goof

12-11-2008, 11:03 PM	#5
The Eagle Senior Member Join Date: Apr 2004 Location: Burlington MA & Moultonboro NH Posts: 218 Thanks: 17 Thanked 142 Times in 33 Posts	Photo correction Hi Lake Geezer! I am pretty sure that photo is of Center Harbor and not Meredith. Youre right, it would make a beautiful X-Mas card! The Eagle

12-12-2008, 12:36 AM	#6
Resident 2B Senior Member Join Date: Apr 2004 Location: North Shore, MA Posts: 1,358 Thanks: 995 Thanked 314 Times in 164 Posts	Raining at a good rate at the Weirs - Temp 28 degrees It is raining at a fairly good rate with the temp at 28 degrees at this time here at the Weirs. The trees are getting loaded with ice. However, the rain rate is keeping the roads somewhat wet and not that icy. The highway folks are doing a great job with sand and salt on the main roads. There are several scanner reports of power line/tree contacts with small fires and a few transformer fires. This is likely to get worse over night. I agree with the previous posters. Great winter scene! R2B

12-12-2008, 12:00 PM	#7
trfour Senior Member Join Date: Nov 2002 Location: The Lakes, Central NH. and Dallas/Fort Worth TX. Posts: 3,694 Blog Entries: 3 Thanks: 3,069 Thanked 472 Times in 236 Posts	Not An Isolated Storm! We even got snow here in Dallas/Fort Worth from this thing! Story; http://www.msnbc.msn.com/id/28193030 __________________ *trfour* Always Remember, The Best Safety Device In The Boat, or on a PWC Snowmobile etc., Is YOU! Safe sledding tips and much more; http://www.snowmobile.org/snowmobiling-safety.html

12-11-2008, 01:21 PM	#2
CanisLupusArctos Senior Member Join Date: Jan 2007 Location: Center Harbor Posts: 1,049 Thanks: 15 Thanked 472 Times in 107 Posts	Snow began late this morning and has accumulated 0.1" before changing over to sleet. The temperature is now 29 degrees and dropping slowly. Soon the sleet will change to freezing rain. The National Weather Service is advising that travel be curtailed this afternoon and tonight except in an emergency. Ice accumulations of an inch are possible. Like R2B said, ice storms are very difficult to predict because they involve layers of different-temperature air stacked on top of each other at different altitudes. It can behave the same way as the lake water mixes at various depths early in the summer - you get warm spots and cold spots and when you jump in, you never know what you're going to get.

12-11-2008, 05:32 PM	#3
NHKathy Senior Member Join Date: Sep 2004 Location: Moultonborough when I can / RI Posts: 699 Thanks: 180 Thanked 38 Times in 22 Posts	so pretty! hope fully not too slippery or dangerous though...