First Alert Weather

Why Is It Snowing When It's Sunny Outside?

Our temperatures in southern New England have reached the upper 40s today, but northern New England has seen highs in the 30s, and those temperatures get way below freezing up in the atmosphere where condensation and precipitation begins, allowing for snow to fall.

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While it’s a decent day in southern New England, areas in western Massachusetts, Vermont and New Hampshire have seen snow today! The key to this wintry precipitation begins with the westerly flow we have. When that west wind comes in contact with our mountain topography, the air stomps into it and finds a new route - right up!

This is known as orographic lifting, or upslope flow. This rising air will cool down even more, and if cooling is sufficient, water vapor condenses resulting in cloud formation and precipitation.

Depending on the temperatures, this precipitation may fall as rain or snow. This is the reason why the windward sides of mountains and hills tend to receive more snow than the surrounding areas in during winter. High amounts of moisture and a steady wind pattern may even be capable of producing feet of snow!

In this case, our temperatures in southern New England have reached the upper 40s today, but northern New England has seen highs in the 30s, and those temperatures get way below freezing up in the atmosphere where condensation and precipitation begins, allowing for snow to fall.

Mt. Washington, for example, with an elevation over 6,000 ft, has seen snow and temperatures in the single digits this afternoon. The wind chill there is -22 degrees! The wind is gusting strong and the visibility is down to zero. Meanwhile, the sun keeps peeking here and there in the south.

Today: Sun to building clouds, isolated rain/snow shower, brisk breeze. Highs in the 40s. Overnight Thursday Night: Chilly, partly cloudy. Lows in the 20s. Friday: Fair with a brisk breeze. Highs in the 40s.
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