Mild, clammy with rain coming and the Rainfall/Snowfall calculation

Good Morning Augusta

This Morning it is cloudy with a high near 45F. Winds are East at 5 to 10 mph.

Tonight we’ll have rain and Lows at or below 41F. Winds will remain out of the East at 10 to 20 mph. Chance of rain 100%. Rainfall around a half an inch.

The readings from my instruments are:

Humidity is 82%, the dew point is 28ºF, its 33.5ºF outside with a wind chill of 33.5ºF.

The wind direction is North Northwest between 0.6 mph and 1.3 mph.

The Barometric pressure is 30.12 HPA 1018 and falling with a weather graphic predicting rain.

The UV rating is 0.0 out of 16, Sunrise is at 7:12 a.m. Sunset is 4:02 P.M. Moon rise is at 2:12 P.M. EST and the moon phase is waxing gibbous.

The METAR reading from Augusta’s airport is:

METAR KAUG 221153Z AUTO 00000KT 10SM SCT080 01/M02 A3007 RMK AO2 SLP186 T00061022 10022 20000 51013

Visibility is 10.0 miles / 16.1 kilometers with scattered clouds down to 8,000 ft / 2,438 m. 

We haven’t had any rain or snow here over the past 24 hours, but its coming for later today and tonight.

 

Not that you need to know this so far this winter, but what is the true ratio of rain to snowfall in inches when it finally decides to snow out there?

 

From WFMZ.com:

Snowfall amounts vary with temperature.  At 32 degrees Fahrenheit the water to snow ratio is equivalent to roughly 1" of rain to 10" of snow.

However, the colder the air, the higher the ratio.

Therefore, at 0 degrees Fahrenheit, 1" of rain can produce as much as 40" of snow!!!!

 

On the other hand -- from Mythbuster on nbcphiladelphia.com:

“When it snows 10 inches does that actually equal one inch of rain?”

I’m sure you’ve heard that claim. It is a commonly shared belief that seems to get regurgitated every time it pours cats and dogs or snows feet.

But, is the legend true?

The quick answer: sometimes.

When the temperature is around 30 degrees, one inch of liquid precipitation would fall as 10 inches of snow -- assuming the storm is all snow.

But, the amount of moisture in each snowflake differs depending on the temperature changing the snow to rain ratio.

For example, our big December snowstorm occurred with temperatures closer to 25 degrees. During that storm the snow ratio was closer to 15 inches of snow to one inch of rain. We had 1.75 inches of "liquid equivalent," yet ended up with 23.2 inches of snow, not 17.5 inches of accumulation.

In fact, I took this into account when forecasting 15 to 25 inches from the Philadelphia area southward for the storm. We even showed a graphic on-air explaining those estimates.

We've had storms with snow closer to 20 degrees -- moving the snow ratio closer to 20 to one. And, when it's warmer (35 to 40 degrees), the ratio moves to 5:1.

So, when someone claims that it's 10:1, PERIOD, you can tell him or her that they're wrong.

 

So, in the final analysis, you have your choice.  You can either say something generally informative like:  “The rule of thumb is that an inch of rain equals 10 inches of snow, but the colder it is, the more that changes.”

 

Or, for those of you who are OCD, annoying, know-it-all hair-splitting types that insist on perfection from those around you at all times and glory in correcting them at every opportunity you can go to CSG network and use their Snowfall to Rainfall calculator.

That lets you be accurate and use temperature, snowfall and other variables to correct almost anyone about the true ratio of rain to snowfall! Enjoy.

 

Or, you can simply take the New Englander conversational approach to snowfall and say:  “Who ****ing cares.  I’m the one who has to go out there and shovel it.”

 

Speaking strictly for myself, I’ve never sat in the kitchen with my early morning coffee watching it snow as I pondered how much rain that would be if it were raining instead of snowing. After I shovel and blow it, I have to rake the roof off too, so who cares?