Astronomy, Photography and Weather

General Category => Weather & Atmospherics => Topic started by: Tyler on December 14, 2008, 08:47:48 pm



Title: Arctic coldfront
Post by: Tyler on December 14, 2008, 08:47:48 pm
Saturday the temperature reached 50F. Saturday Night I was watching the meteor shower in a comfortable 44 degrees. I went to sleep and woke up to snow showers, and an icy temperature of 5F, wind chills at this time were -15 to -20F

Monday the high temperature is 8 degrees F. and wind chills between -15 and -25.

Here is a map of the strong arctic front...This is producing a Blizzard in N. Dakota and Minnesota with 10-20" in some places.

(http://i478.photobucket.com/albums/rr148/Tyler_greatsky/WOAH.jpg)

First Winter Storm Potential Tuesday: Finally we have a chance for a winter storm. I will report the event in this thread by the end of tuesday. here is the latest Forecast Disc.

Quote
WITH COLD
TEMPS SHOULD YIELD SNOWFALL RATIOS APPROACHING 15/17 TO 1. HAVE INCREASED
POPS TO 70 TO 80 PERCENT FOR TUESDAY...AND HAVE UPPED SNOWFALL AMOUNTS
TO A 2 TO 5 INCH RANGE. WINDS WILL HAVE DIMINISHED BY THEN...THUS
JUST EXPECTING A DECENT ADVISORY LEVEL SNOWFALL


Title: Re: Arctic coldfront
Post by: martinastro on December 15, 2008, 02:36:01 am
Thanks for informing us about that Tyler. Hope you get the storm. Looking forward to hear how it pans out. That's nasty wind chill, and what a drop in temp!. That cold front is bound to lift that warmer air up and produce something!  :)...fingers crossed.


Title: Re: Arctic coldfront
Post by: Tyler on December 16, 2008, 04:28:31 am
OKay here is my forecast...

Tuesday...snow starts at 8am ends at 4pm Total accumulations: 4-6" Here is the map...

(http://i478.photobucket.com/albums/rr148/Tyler_greatsky/weather.jpg)

photos coming tommorow night I hope!


Title: Re: Arctic coldfront
Post by: martinastro on December 16, 2008, 02:03:27 pm
I feel cold looking at that Tyler..keep those batteries warm!!, Good luck  :)


Title: Re: Arctic coldfront
Post by: Tyler on December 16, 2008, 09:23:27 pm
well we got dry-slotted... again, this happens often for Omaha. Ended up with 1.5" of new snow. Its still snowing lightly, but the sun is peaking through...watching for a sun halo or sundogs!

I didnt get any good shots of snow falling but here are a few I took this afternoon...

(http://i478.photobucket.com/albums/rr148/Tyler_greatsky/CR1-7.jpg)

(http://i478.photobucket.com/albums/rr148/Tyler_greatsky/CR2-6.jpg)

maybe more snow or ice on thursday, have to see...


Title: Re: Arctic coldfront
Post by: rjgjr on December 16, 2008, 10:35:51 pm
Those are great photos Tyler. I've been watching the news and weather re: the midwest, I have relatives near St. Louis. Some areas are getting blasted. I'm sure the snow is nice, but it's no fun living with it. We had about 2" of snow yesterday, which is very rare for the coastline. I'll try and post some later. They were just taken around my house. Was going to try and get to the beach and take some, but our service road was so steep and icy I didn't want to try it.

Richard


Title: Re: Arctic coldfront
Post by: rjgjr on December 16, 2008, 11:48:47 pm
Hi Tyler and all. Here are a couple of photos of the aftermath of our big coastal snowstorm. Most of the world will laugh at the amount of snow, but by our standards, it's a big headache. It dropped all the way down to 30 F this morning.

Here is my little weather station doing something besides measuring rainfall for a change.

(http://i42.tinypic.com/16a2u52.jpg)

The Pacific Ocean didn't freeze.

(http://i44.tinypic.com/9urlo1.jpg)

Richard


Title: Re: Arctic coldfront
Post by: martinastro on December 17, 2008, 05:24:57 pm
Tyler and Richard, thanks alot for sharing those very nice snow images. It looks like a decent snow fall. Tyler, love that image looking up the stream with snow on the bank  :)

Richard, that's a very cool image of the snow falling over the Ocean! - dramatic indeed.


Title: Re: Arctic coldfront
Post by: Roman White on December 17, 2008, 10:59:45 pm
Tyler and Richard, I see you both have a nice winter.  ;) I have already a week of winter (below 0C=32F), but there's a very little (very very little) amount of snow.

Here is my little weather station doing something besides measuring rainfall for a change.
I'm curious, can those weather stations measure a snow as a rainfall or they stop working at conditions like that? 

The Pacific Ocean didn't freeze.
...But it froze near Hawaii  ;D Nice joke


Title: Re: Arctic coldfront
Post by: rjgjr on December 18, 2008, 12:49:02 am
You know Roman, we have so little snow here(sometimes not every year), I don't know what is correct. I usually just let the snow melt down and it goes through the tip bucket and I just measure it as precipitation. I've heard that 10" of snow equals 1" of water, and that usually seems to work out pretty close. I'll have to email our weatherman over at the T.V. station in the big city and see what he says about it. I've always been curious too!

Richard


Title: Re: Arctic coldfront
Post by: Tyler on December 18, 2008, 01:54:23 am
You know Roman, we have so little snow here(sometimes not every year), I don't know what is correct. I usually just let the snow melt down and it goes through the tip bucket and I just measure it as precipitation. I've heard that 10" of snow equals 1" of water, and that usually seems to work out pretty close. I'll have to email our weatherman over at the T.V. station in the big city and see what he says about it. I've always been curious too!

Richard

Richard, Snow-Liquid equivilent ratios vary from storm to storm, but for the most part the average is 10 to 1, our most recent storm dropped ratios of 17 to 1. There have even been reports of 35 to 1 ratios!

no problem Martin, when there arent clear skies, you got to shoot something else! (hopefully thursday that something else will be a 1/2" coating of Ice on everything :) that would make for some great photos) Ill keep you guys posted, I have been disscussing the next storm on another forum for a couple days now, and we are all anticipating the storm!


Title: Re: Arctic coldfront
Post by: brianb on December 18, 2008, 08:38:06 am
Quote
can those weather stations measure a snow as a rainfall or they stop working at conditions like that? 
The funnel clogs up.

I understand the procedure for measuring snowfall is to have a large flat surface which is swept clean. After the snowfall take a "core" using a 6" diameter pipe which goes down to the surface, melt the snow & ice down, pour into a 1" diameter tube, measure the height of the water column & divide by 36. Sweep the collecting surface & repeat. (As done in arctic & antarctic met stations)


Title: Re: Arctic coldfront
Post by: martinastro on December 18, 2008, 12:35:53 pm
Looks like you guys could be in for an ice storm!. Lots of photogenic potential there. Sounds exciting!  :)


Title: Re: Arctic coldfront
Post by: rjgjr on December 18, 2008, 03:56:13 pm
Quote
can those weather stations measure a snow as a rainfall or they stop working at conditions like that? 
The funnel clogs up.

I understand the procedure for measuring snowfall is to have a large flat surface which is swept clean. After the snowfall take a "core" using a 6" diameter pipe which goes down to the surface, melt the snow & ice down, pour into a 1" diameter tube, measure the height of the water column & divide by 36. Sweep the collecting surface & repeat. (As done in arctic & antarctic met stations)

With the scant amount of snowfall we get at one time(1-2"), I don't think I could get that amount to stick in a core, but that sounds like a plan. I've heard of the flat surface and measuring snowfall depth concept before. Thanks for the info.

Richard


Title: Re: Arctic coldfront
Post by: Tyler on December 19, 2008, 07:30:29 am
Well this storm turned out to be another bummer... :'( JK

We started of with Freezing rain, but quickly changed to sleet, accumulated about 1" of sleet, then went back to freezing rain, back to sleet, now its snowing lightly, but only expecting an inch of snow at most. The Highlight of the storm was witnessing some rare "thundersnow"  which is convective snow showers. I also (semi) documented on camera. I saw a flash of lightning durning sleet, which would be called Thundersleet. Anyways there are two photos, the first is a normal shot, lightning occured in the second shot, illuminating a purple hue to the photos. (lightning to the NW, camera faceing SW) sorry if this is confusing, but its late...maybe tommorow ill revise this, but I cant think very well right now

(http://i478.photobucket.com/albums/rr148/Tyler_greatsky/CR1-8.jpg)

(http://i478.photobucket.com/albums/rr148/Tyler_greatsky/CR2-7.jpg)


Title: Re: Arctic coldfront
Post by: brianb on December 19, 2008, 08:18:25 am
Quote
With the scant amount of snowfall we get at one time(1-2"), I don't think I could get that amount to stick in a core
Slide a card under the end of the tube?


Title: Re: Arctic coldfront
Post by: brianb on December 19, 2008, 08:20:51 am
Quote
The Highlight of the storm was witnessing some rare "thundersnow"  which is convective snow showers.
Hmmm, round here almost all the snow that falls is from wintry convection ... snow falling from frontal cloud is very rare & almost always turns to sleet then rain in a very short time.


Title: Re: Arctic coldfront
Post by: martinastro on December 19, 2008, 12:34:41 pm
Tyler, you done a very good dob with those images. The two images really show how bright that lightning was. I can imagine what it was like being there. Thundersnow is not easy to catch but you done it!.  Like the car trail in the first, the second looks very festive. Sorry to hear the forecast was a bummer but at least you got some snow and sleet with lightning!  :)

I seen thundersnow last Jan but I have yet to get an image of it.

Thanks for the updates


Title: Re: Arctic coldfront
Post by: Roman White on December 19, 2008, 12:49:59 pm
I liked the images too. Waiting for more photos of your winter, Tyler  :)