You may have taken your time to locate your snow shovel this week, but you're unlikely to need it in the next few days, says the National Weather Service.
As temperatures continue to drop, forecasters say that low pressure The system will remain offshore as it passes south and east of our region on Friday night and Saturday. Translation? As the first real clue of winter arrives, you can pull the blankets over your head and go back to sleep on Saturday. There will be no snow to clean here in Lehigh Valley.
Meanwhile, the weather service says that a second low-pressure system that passes through the Great Lakes will finally move through our region from Saturday to Sunday. Unfortunately, there can only be some rain and / or snow with your step. The Lehigh Valley can see only one layer of snow in general, while the expected snow in Poconos could reach about a half inch on Saturday night.
The forecast of a winter storm
It is not a secret that predicts winter storms our area can be very challenging for meteorologists. While the rest of us can play armchair quarterback from the warmth of the living room, local forecasters are grappling with numerous variables that come into play when it comes to determining the precise impacts of upcoming weather systems. As we have seen in past years, even small changes in these variables result in large changes in the forecast.
So, what exactly do the National Meteorological Service meteorologists look at when predicting winter storms? There are some important variables that go into the prognosis process, which include:
1. Track. For local meteorologists to predict systems more than a day or two in advance, they look and rely on a series of computer models that make predictions based on a set of complex equations. There are numerous models available, including those you have undoubtedly heard, such as the Meso-Scale of North America (NAM) and the Global Forecast System (GFS). But all of them can show incredibly different solutions to each other beyond the time frame of 48 to 72 hours. If you follow anyone on Twitter who is enthusiastic about the constant promotion of these colorful models, you are familiar with how often the forecast can change as the storm system approaches a particular area.
2. Humidity. It is simply the key ingredient of a winter storm. Since the atmosphere is usually cold and dry in winter, sometimes approaching storm systems do not have enough humidity to work to produce significant precipitation.
3. Temperature. It plays a vital role in determining the type of precipitation that affects the soil. A change of only 2 or 3 degrees can mean the difference between rain, freezing rain, sleet or snow.
If you are a snow lover tormented by the fact that the next forecast is not what you expected, at least you can embrace the cold. In fact, the weather service says the coldest air mass of the season could be incorporated into the region by the middle of next week. The current model guide indicates highs at 20 to 30 lows on Wednesday.
Here is the extended Lehigh Valley forecast from the National Weather Service:
Sunny, with a high near 44. Wind West wind between 5 and 11 mph, with gusts as high as 21 mph.
Partly cloudy, with a low around 24. West wind between 3 and 6 mph.
Partly sunny, with a high near 38. Calm wind becoming west between 5 and 7 mph in the morning.
Mostly cloudy, with a low around 24. Light west wind.
A slight chance of rain after noon. Partly sunny, with a high near 37. Calm wind becoming south around 5 mph. Possibility of precipitation 20%.
A slight chance of snow. Mostly cloudy, with a low around 24. Chance of precipitation is 20%.
Mostly sunny, with a high near 36.
Sunday Night  Partly cloudy, with a low around 20.
Mostly sunny, with a high near 39.
Mostly cloudy, with a low of 27.
A chance of rain and snow. Mostly cloudy, with a high near 38. Chance of precipitation is 30%.
Mostly cloudy, with a low around 19.
Wednesday 19659002] Mostly sunny, with a high near 27.