Final Snowfall Forecast : Monday 2/1 – Tuesday 2/2

Winter Storm Warnings are beginning to be issued across the southern Hudson Valley, and soon to be followed across the remainder of the Hudson Valley, as we track an evolving complex storm system that is now likely to be a major event for our region.

Timing :
– 9pm Sun – 2am : Light snow develops over southern half of HV
– 6am to 10am : Moderate snow develops from south to north
– 10am to 6pm : Moderate to Heavy snow
– 6pm Mon to 12am Tue : Light to moderate snow
– 12am to 6pm Tue : Periods of light to moderate snow tapers

Impacts/Conditions:
– Long Duration event expected, snow could last over 24 hours
– Monday AM commute likely impacted, especially from I-84 on south
– Accumulating snow may be delayed until morning in northern half of HV
– Heaviest snow likely late Monday morning through Monday evening
– NE winds 10 to 20mph, gusts over 30mph, blowing & drifting snow
– White out / Blizzard conditions possible at times
– Extremely difficult/dangerous travel Monday PM – Tuesday AM

Snow Accumulations:
– Eastern Catskills (Zone 2) : 18 to 24 inches (locally up to 30″)
– Majority of Hudson Valley : 12 to 20 inches (locally up to 24″)
* Red Circles = Downsloping dry air, potential lower amounts of 8″ to 14″
** Banding across mid/lower HV could result in localized reports up to 24″

— HVW Discussion —

No major changes to the basic structure and concept behind how this storm develops and impacts the Hudson Valley.  The primary changes, are in the amount of available moisture for our region.  Computer guidance is now consistently depicting 25% to 50% more moisture than at the time we created the preliminary forecast.  The result would be snow bands of 1 to 3 inches per hour during the day on Monday, combined with NE winds gusting over 30mph at times.  The stage is set for absolutely horrendous travel conditions Monday afternoon through Tuesday morning.

Futurecast Radar : 6pm Sunday – 6am Tuesday

This 36 hour radar loop shows that the potential exists for light snows overnight Sunday night in many portions of the Hudson Valley (lower half especially).  The start time of this event is going to vary greatly by location.  Some guidance has the snow starting by 8pm tonight south of I-84, other guidance waits until after midnight.  Some guidance delays start times for the northern half of the HV until near sunrise on Monday, other guidance says it’s snowing before midnight.  The problem, is dry air.  How strong and persistent is the dry air?  We’ll see.  But keep in mind that conditions could deteriorate before sunrise on Monday.

We’ll see an increasing band of heavy snow pushing northward Monday morning into Monday afternoon.  The heaviest snow is likely from late morning through early evening Monday, before the storm literally begins to ‘snow itself out’ Monday night.  The low pressure will sit and spin off shore the entire time, which means there are unanswered questions about how much (if any) snow continues to fall as we push into Tuesday around the region.  Notice by the end of the loop that the heavier snow pushes north of our area, but light snow showers are projected to continue falling.

When all is said and done, we feel the HRRR solution paints a very possible solution of snowfall across the region.

The position of the heaviest snow bands will be the determinant of who sees upwards of 20″ from this storm.  Much guidance says that the Hudson Valley will be where that occurs, but we can’t be certain.  The result is our wide range for a general 12 to 20 inches of snow.  We have concerns about moisture availability in some areas… especially the downslope locations circled in the snowfall forecast map.  In those areas, downsloping may dry the air enough to reduce snowfall amounts by up to 6 inches compared to areas surrounding them.  So a few locations may struggle to meet the snowfall forecast range.

In addition, some locations will see heavier bands of snow than others.  This will give the potential for some places to eclipse 20″ of snow.  Another factor in the wide snowfall forecast range.

Winds will also be an issue….
Futurecast Winds:  1am Monday – 1am Tuesday

Gusts out of the northeast between 25 and 40mph, will create blizzard conditions across the entire region, especially the higher terrain.  Areas in the Catskills could see gusts up to 50mph.  This will blow and drift the snow over 2 or 3 feet in some areas, creating possible white out conditions at times, and making travel virtually impossible late on Monday.  The snow is going to be a rather fluffy powder, and will not stick to trees and powerlines.  So our hope is that power outages will be minimal.  But anytime you have gusts over 35mph, the risk of outages will exist.

We will continue to update things over the next 36 hours, as we track a major winter storm for the Hudson Valley.