A dopey myth some here hold gets another beating about the head and face

[JamieOber]

Warm ground means snow can't accumulate AT ALL. See: http://www.americanw...12#entry1004912

Yes, it definitely is a factor at times, but I am posting this so the next time some idiot proclaims that snow forecasts are going to be wrong because snow CAN'T accumulate due to warm ground, people with brains can link to this.

Thanks.

[JamieOber]

Also, note snow accumulated on roads.

[Stebo]

Warm ground means snow can't accumulate AT ALL. See: http://www.americanw...12#entry1004912

Yes, it definitely is a factor at times, but I am posting this so the next time some idiot proclaims that snow forecasts are going to be wrong because snow CAN'T accumulate due to warm ground, people with brains can link to this.

Thanks.

Most of April 2005 was in the 60s and 70s with April 19th 2005 DTX's area was in the 80s, but by April 24th most of DTX's area had between 6-12" of snow some areas close to 18". I hear exactly what you are saying.

[JamieOber]

Most of April 2005 was in the 60s and 70s with April 19th 2005 DTX's area was in the 80s, but by April 24th most of DTX's area had between 6-12" of snow some areas close to 18". I hear exactly what you are saying.

Yeah, stuff like rates can overwhelm warm ground. April 1 1997 is another example.

[JoMo]

Depends on snowfall rate. Did that snow melt off after it stopped snowing and if temps were above freezing?

[Midlo Snow Maker]

canaan valley wva picked up 3.4" yesterday, even the NC mountains picked up some snow

[Lee]

Warm ground means snow can't accumulate AT ALL. See: http://www.americanw...12#entry1004912

Yes, it definitely is a factor at times, but I am posting this so the next time some idiot proclaims that snow forecasts are going to be wrong because snow CAN'T accumulate due to warm ground, people with brains can link to this.

Thanks.

The sad thing is, many Mets feel that way. Of course it's a factor but, if it snows heavy enough, it's still going to accumulate, bottom line.

[Itunis]

Huh? The ground wasn't THAT warm. With the rain yesterday with temps in the mid 40s the ground was probably about that temperature. There have been some events back in the SE where it was well into the 60s with full March sun for a few days beforehand and believe me, the ground (and the heatsinks called roads) ate up a lot of snow.

Edit-But I'm not one of the people saying it WON'T accumulate on warm ground, just that the ground temperature should be taken into account when forecasting snow totals.

[isohume]

This thread is eyeopening. lol

[Stebo]

Huh? The ground wasn't THAT warm. With the rain yesterday with temps in the mid 40s the ground was probably about that temperature. There have been some events back in the SE where it was well into the 60s with full March sun for a few days beforehand and believe me, the ground (and the heatsinks called roads) ate up a lot of snow.

Edit-But I'm not one of the people saying it WON'T accumulate on warm ground, just that the ground temperature should be taken into account when forecasting snow totals.

The temps for the last 2 weeks in Central PA have been in the 70s and the lows have been at least been in the mid to upper 50s, up until 3 days ago. I'd have to imagine the soil temperatures weren't in the 40s.

[JamieOber]

Huh? The ground wasn't THAT warm. With the rain yesterday with temps in the mid 40s the ground was probably about that temperature. There have been some events back in the SE where it was well into the 60s with full March sun for a few days beforehand and believe me, the ground (and the heatsinks called roads) ate up a lot of snow.

Edit-But I'm not one of the people saying it WON'T accumulate on warm ground, just that the ground temperature should be taken into account when forecasting snow totals.

lol. Here are the temps for the week leading up to the snow:

76/63

78/67

70/65

71/59

65/55

61/46

49/36

Reason why I point that out is because people here will use temperatures leading up to an event to whine they aren't going to get snow.

Of course it's a factor. But anyone who thinks it's a dealbreaker has the IQ of a brain-damaged amoeba.

[JamieOber]

The sad thing is, many Mets feel that way. Of course it's a factor but, if it snows heavy enough, it's still going to accumulate, bottom line.

Any met who thinks that should pay more attention to data. It's a plain stupid line of thinking.

[SnowGoose69]

A significant snow event, especially if it occurs at night will usually overcome warm ground or soil temp issues. This is mainly a factor in late November or December events but when people try to use that argument in March or even April its less effective. Even the 11/29/95 event near NYC when it had been in the 60s the day prior and was still just late November saw the snow accumulate on roads.

[wxsmwhrms]

If the logic of those who hold the myth were correct, there would NEVER be accumulating snow in the Deep South. Having forecasted in the South for more than 15 years, I have never seen ground temps have a major impact on snow totals during a true accumulating snow event. You might lose a little at the very front end, and obviously once it quits snowing you will start a gradual melting process immediately. But it just doesn't matter in the way some people think.

I did actually get into an argument with a fellow forecaster while forecasting a lake effect event in the beginning of my met career many years ago. It was in late October, and he was insistent the "snow wouldn't stick." I believe my last point was a rather shrill "when the 3 inch per hour rates kick in, I assure you it WILL stick." 18" later, I felt vindicated...

[isohume]

Any met who thinks that should pay more attention to data. It's a plain stupid line of thinking.

haha...I wouldn't believe everything you read.

[WxUSAF]

Did downtown SC get any snow, Jamie?

[JamieOber]

Did downtown SC get any snow, Jamie?

Just flakes, which is crazy enough.

[CoastalWx]

Wet snow especially will stick to anything. If you have water logged snow falling mdt or greater, it will stick much easier than silver dollar fluff falling to the ground. Water content is defintely a factor. I've seen fluff have a problem sticking late in the season, but even that can be overcome by rates that are high enough.

[ORH_wxman]

Intensity is the overriding factor. Warm ground or marginal sfc temps can inhibit accumulation if the intensity remains light, but once you start get getting moderate to heavy snow, the ground temp won't make much of a difference.

[tacoman25]

Apparently none of you are aware of the Ground Temperature to Snowfall Intensity Formula. This is how it works: for every degree above freezing the ground is, the snow must come down .01" (water content)/per hour to stick. So if you have frozen ground, any snowfall intensity will produce accumulation. If the ground is 35, the snow must come down at least .03"/per hour to accumulate. If the ground is 39, .07"/hour. Temp of 45, .13"/hour. If your ground temperature is 80 degrees, you will need a precip rate of .48"/hr or roughly 5"/hr of snowfall (going by 10 to 1 ratios) to see accumulation.

I have utilized this formula for years and it has never let me down.

[OSUmetstud]

Apparently none of you are aware of the Ground Temperature to Snowfall Intensity Formula. This is how it works: for every degree above freezing the ground is, the snow must come down .01" (water content)/per hour to stick. So if you have frozen ground, any snowfall intensity will produce accumulation. If the ground is 35, the snow must come down at least .03"/per hour to accumulate. If the ground is 39, .07"/hour. Temp of 45, .13"/hour. If your ground temperature is 80 degrees, you will need a precip rate of .48"/hr or roughly 5"/hr of snowfall (going by 10 to 1 ratios) to see accumulation.

I have utilized this formula for years and it has never let me down.

i'm guessing there is some assumption built into this formula that the surface temperature/air temperature will continue to drop?

[tacoman25]

i'm guessing there is some assumption built into this formula that the surface temperature/air temperature will continue to drop?

Perhaps.

Actually, I was just having fun with this whole discussion...I don't really use that "formula", I just decided to come up with something that sounded half-way plausible.

[OSUmetstud]

Perhaps.

Actually, I was just having fun with this whole discussion...I don't really use that "formula", I just decided to come up with something that sounded half-way plausible.

lol

[Shawn]

There has been snow into April around SC. Granted down here in the South it really doesn't stick around long at all.. but elsewhere.... although it happens down here.. snow can and will stick to above freezing ground temps especially if it comes at a heavy rate. The melting snow tends to cool the surface down pretty well and if it keeps up.. it sticks. You lose out on a bit due to the melting/cooling but in the end even a dusting down in SC is wonderful and worth the track. (:

[skierinvermont]

This isn't to say that many people don't overuse the warm ground argument but I remember one time when it had been in the 50s and 60s for weeks, even the day before the storm was in the 50s or 60s, and although 1.5" of snow accumulated, it melted in an hour despite temps in the mid 20s... then the snow started back up again and by this time temps had fallen to 18-19F... again 2.5" accumulated by around 4pm. The next morning there was only 1" left despite overnight temps around 10F. The surface of the snow had frozen but when you walked on it you would break through into the slush and mud underneath. It took over 24 hours for the snow to freeze solid and the melting to stop from underneath.

We probably would have had 6-8" of snow on the ground if ground temps had been colder... instead we ended up with 1". And it wasn't for lack of intensity either.. the two bursts snowed like crazy 1.5" in the first burst 2.5" in the second but it quickly melted after each burst.

The craziest part was the air temps starting in the mid 20s falling to the low teens and yet the snow kept melting.

[CoastalWx]

This isn't to say that many people don't overuse the warm ground argument but I remember one time when it had been in the 50s and 60s for weeks, even the day before the storm was in the 50s or 60s, and although 1.5" of snow accumulated, it melted in an hour despite temps in the mid 20s... then the snow started back up again and by this time temps had fallen to 18-19F... again 2.5" accumulated by around 4pm. The next morning there was only 1" left despite overnight temps around 10F. The surface of the snow had frozen but when you walked on it you would break through into the slush and mud underneath. It took over 24 hours for the snow to freeze solid and the melting to stop from underneath.

We probably would have had 6-8" of snow on the ground if ground temps had been colder... instead we ended up with 1". And it wasn't for lack of intensity either.. the two bursts snowed like crazy 1.5" in the first burst 2.5" in the second but it quickly melted after each burst.

The craziest part was the air temps starting in the mid 20s falling to the low teens and yet the snow kept melting.

Because water content was probably extremely low. Sometimes that happens, but in most of the circumstances where the term "snow may not stick all that well due to warm ground" , it usually occurs in an event producing wet snow. That's the stuff that will stick to everything despite warm ground. In your case, the snowfall rates were probably not high at all, either.

[skierinvermont]

Because water content was probably extremely low. Sometimes that happens, but in most of the circumstances where the term "snow may not stick all that well due to warm ground" , it usually occurs in an event producing wet snow. That's the stuff that will stick to everything despite warm ground. In your case, the snowfall rates were probably not high at all, either.

Well each burst only lasted a couple hours and each was 1.5 and 2.5" accumulated despite a lot of that melting on contact. So the snowfall rates were very high .. but you are right the water content was probably pretty low with temps in the mid 20s falling to the low teens. When it snowed hard it accumulated faster than it melted but as soon as it stopped it would melt quickly despite the very cold air temps.

[Ian]

This is an argument both sides are pretty annoying about