Vigorous Upper-level Low Pressure to Bring Accumulating Snow to Parts of Connecticut Overnight 04/15/21 to 04/16/2021

 A vigorous upper-level low pressure system across New England prompts the developments and strengthening of a surface low pressure right in the vicinity of Connecticut moving through Thursday night. If the processes involved with this system occurred say another 50-75 miles farther south and east..at least the northern part of the state would be looking at a pretty significant winter storm, however, looks like the most significant snows occur across parts of western Massachusetts, southern Vermont, and perhaps around the Worcester Hills in east-central Massachusetts. 

As of Thursday afternoon moderate-to-heavy rain has overspread much of Connecticut. As we move into the overnight and the low pressure system really gets its act together, anomalous cold will transpires within the lowest levels of the atmosphere. In fact, surface temperatures look to even dip as low as the mid-30's and even colder across the hills. As this occurs rain begins to transition to snow across the hills and even parts of northern Connecticut. In fact, the majority of the state could even some some snow mix in with the rain. 

This is a highly complex setup due to the features and processes involved, however, forecast models have been zeroing in on a solution which features a band of heavy snow which becomes established across southern Vermont through the Berkshires of western Massachusetts even extending into extreme northwestern Connecticut. This would result in a several-hour period of moderate-to-heavy snow overnight. Snowfall rates could approach 2'' per hour so despite the warm ground, these rates, combined with it being overnight would result in snow accumulating, though taking a bit longer on paved surfaces. Another band of moderate-to-heavy snow looks to originate across the Worcester Hills of east-central Massachusetts with this band pivoting and clipping parts of northeast Connecticut Friday. 

Given this snow will be wet in nature and very heavy, the potential exists for downed tree limbs and power lines. In fact, scattered-to-numerous power outages could be expected in areas which receive greater than 4'' of snow...power outages could even be on the widespread side. 

This is a very dynamic storm and add in the time of year and you get a very challenging forecast which is ultimately going to come down to nowcasting...meaning we won't really know how the situation unfolds until the processes involved get going. 

What to Expect:

• Moderate-to-heavy rain persists through the overnight
• Around midnight, rain begins to mix with and change over to snow across the northwest and northeast hills with snow becoming moderate-to-heavy through the overnight. 
• The heaviest of the snow across the northwest hills winds down between 6:00 - 8:00 AM Friday morning, however, moderate-to-heavy snow may persist through much of the morning across parts of northeast Connecticut. 
• The majority of the state may see some snow mix in, however, most people will probably be counting cows when this happens. 
• Gusty and cold Friday with temperatures only into the lower 40's with a stiff northwest wind gusting 20-25 mph.

Below is what I am currently expecting in terms of snowfall accumulations: