Mid-Atlantic Blizzard 24 Hours Away

    Blizzard Watches are now posted from Philadelphia to New York City (likely to become warnings for most by tomorrow), while Blizzard Warnings encompass large areas of Maryland and northern Virginia.  We're now roughly 24 hours from go-time in South Jersey, where the first flakes begin falling toward midnight tomorrow night.  The storm likely lasts for around 24-30 hours across the area and will bring a combination of wet and heavy snow, high winds, and coastal flooding/erosion (to the coast).  Below is a general depiction of the storm, from this afternoon's GFS, off of the Virginia coast, as it throws heavy snow bands and winds into New Jersey for the first half of Saturday.

This afternoon's GFS shows possible blizzard conditions for the first half of Saturday (tropicaltidbits.com)

Timing
Start time: 9pm through midnight from south to north across South Jersey
Heaviest: Overnight hours through Saturday afternoon (snowfall rates of 1-3" per hour likely); thundersnow is also a possibility, so keep an ear out for it!
End time: Still a bit uncertain, but snow looks to generally fizzle out late Saturday night

Impacts
    Overall, not much has changed in general since my last post in regard to the overview of the storm, so I'll just talk about the general impacts of this weekend's nor'easter:
-We'll see a heavy, wet snow out of this system, which will be tough to shovel and also weigh down on tree limbs, power lines, etc.
-Winds will be another major threat, as winds likely gust inland to 40-50 mph (20-30 mph sustained) and gust to 60+ mph along the coast
-The combination of heavy/wet snow and wind (possible blizzard conditions) could cause power outages across the state
-Very strong onshore winds, high tides, and a full moon will all combine to produce major coastal flooding which could devastate beaches and coastal communities

Snow Map
    There are still question marks in regard to snow totals despite my map not changing much since my first call.  The shore still likely sees less due to the threat of some mixing issues Saturday morning/early afternoon due to the strong onshore flow from the ocean.  As of now, the 'jackpot' area looks to be a strip of the state from Southwest Jersey through Central Jersey.  North Jersey, at this time, is on the border of a strong gradient between light accumulations and being in on plow-able snow.  Any shift north or south (there have been some very recent trends north) could either put North Jersey at even less snowfall or in on the high accumulations shown for the southern half of the state.  I'll have a final update tomorrow if needed!  

My Second Call Snow Map

Major Mid-Atlantic Snowstorm Incoming

    We're now roughly 48 hours away from go-time in New Jersey with the impending winter storm that has been talked about for days now.  Models have shown remarkable consistency with this storm for several days now, and as its energy begins its descent into the Southeast, they continue to show a major, even possibly historic, Mid-Atlantic nor'easter for the weekend.  The National Weather Service in Baltimore posted Winter Storm and Blizzard Watches earlier all across Maryland and northern Virginia, and the Mount Holly office followed with their own group of Winter Storm Watches for our area.  I wouldn't be surprised if portions of New Jersey saw Blizzard Watches/Warnings as well over the next 48 hours.  Below is a glimpse at what the GFS depicts as our storm on Saturday.

GFS model run depicting general conditions Saturday midday (tropicaltidbits.com)

Overview
    As stated in my post yesterday, energy that worked its way into the Pacific Northwest last night is currently diving south through the Plains states.  The system will then round toward the east as it descends into the Southeast.  Then it move northeast and exits the east coast around the Outer Banks of North Carolina Friday night.  During this time, the low pressure system will strengthen, bringing an onslaught of moisture (mainly in the form of snow) and high winds to the Mid-Atlantic, with the bulls-eye looking to set up over Maryland and northern Virginia.

GFS model run showing high winds across coastal and southern NJ Saturday (tropicaltidbits.com)

Impacts and Estimated Timing
    We'll likely start seeing the first flakes fly in New Jersey from south to north after 7pm on Friday evening.  Snow will quickly become heavier overnight and into Saturday afternoon, which is the time period where we likely see the heaviest snowfall rates and even the possibility of thundersnow.  Though I believe areas toward Philadelphia remain all snow for the storm, the mixing line will have to be watched, particularly on Saturday morning.  As the low continues to approach offshore, winds will reach a peak intensity, with inland areas seeing 20-35 mph sustained winds and gusts to 40-50 mph, while coastal areas likely see gusts of strong tropical storm strength (upward of 60+ mph).  It then looks like snow begins to fizzle out late Saturday or early Sunday morning.

    The snowfall with this system is going to be of the wet variety, which is good for snowballs but bad for shoveling.  This, combined with high winds, will cause the risk of power outages, especially for areas closer to the shore where winds will be at a maximum.  The wind and heavy snow combination with this storm is why I wouldn't be surprised if we saw Blizzard Watches/Warnings posted at some point.  Furthermore, for coastal areas, the combination of strong onshore winds, high tides, and a full moon will likely cause major coastal flooding and beach erosion.  This is a part of the storm that has been relatively unmentioned, and some spots are even forecasted to see tides rival, or possibly exceed, those seen during Hurricane Sandy!

First Call Snow Map
    Finally, at this time, the stripe of highest snow amounts looks to run from Southwest Jersey through Central Jersey, where we could see upward of 12-18" of snowfall.  Along the coast in South Jersey, things are more questionable due to the possibility of sleet and rain mixing in, so I left that area lower for now at 6-12" (higher if it remains all snow).  As you approach North Jersey, amounts likely lower as you move away from where the heaviest bands of snow look to set up.  Then, there will likely be a sharp cutoff in heavy snow amounts to lighter accumulations along the Northwest Jersey/New York border.  Below is my first call for this weekend's snowstorm, and I'll post an updated map and blog with any new details tomorrow!

My First Call Snow Map

 


 

 

Potential for Major Winter Storm to End Week

    After a relatively snow-less winter thus far, snow lovers look like they will finally see their first big break of the season as a potentially major winter storm for New Jersey threatens for the end of the week.  The energy that will be the cause of this system is currently moving onshore in the Pacific Northwest and will begin its long, meandering journey across the nation throughout the latter half of the week.  What could potentially result from this nor'easter would be a barrage of snow, winds, coastal flooding, beach erosion, and a spike in bread and milk sales.

Overview
    Essentially, the low pressure system entering the northwest, and its associated energy, will ride over a ridge in the western half of the US.  It will then proceed to then dig toward the south across the Plains and enter the Southeast.  From there, our system will really begin to strengthen and where it heads from that point will determine our storm potential.  We are now now around 72 hours away from go-time, and models will now begin to get a better hold on the system as they can now "see" it better with the energy now moving over land.  Below is a basic overview of the path that the storm will likely take, but its exit along the East Coast will really help to determine our exact weather outcome for Friday/Saturday.

Rough estimated path that the storm take throughout the week with an unknown exit in the east

Where and When?
    Right now, the timing of this system has been fairly consistent with a start during the PM hours on Friday and ending Saturday night, so we're talking upward of a 24-30 hour storm.  However, the real uncertainty, as is in all winter storm forecasting, is narrowing down the exact track.  This is absolutely crucial to determine who sees mixing if at all, where the heaviest snow sets up, where there will be a sharp cutoff in snow totals, etc.  At this time, an exit off the coast between the Delmarva peninsula and the Outer Banks of North Carolina looks to be the best chance at this point.  However, such a large spread is what makes forecasting snow totals so variable at this time frame.

This afternoon;s GFS model run shows the storm for the first half of Saturday (tropicaltidbits.com)

Impacts
    This storm will likely have an impact on communities from North Carolina up through New England and everywhere in between along the I-95 corridor.  The heaviest stripe of heavy snow currently looks to lie in a region from Virginia into Maryland and then through Southeast Pennsylvania and New Jersey.  Here, we could "POTENTIALLY" see snowfall totals upward of a foot and/or higher (which has been modeled for days now).  High winds will accompany this snowfall as the low strengthens near the region, and we may even have to bring out the "B word" (blizzard) if things line up correctly in some areas.

    Finally, impacts that may not get as much 'glamour' and conversation as snowfall will greatly affect the coastal areas of New Jersey and the rest of the Mid-Atlantic coast.  There, we will likely see long durations of tropical storm force winds of 50+ mph coming ashore.  When you pair this up with a full moon and high tides, we will be looking at major coastal flooding and extensive damage to beaches.  The shore areas will carry that dual threat of water and snow while areas inland prepare for possibly heavy snow accumulations.

    My first call snow map will likely be out tomorrow evening, along with updates and more details about what we may expect to end the week!

Clipper to Bring Snow/Rain Showers Tuesday

Overview

    Tomorrow, a weak clipper will dive out of the Upper Midwest and cut through the Great Lakes/Northeast to our north throughout the day.  Ahead of it, highs will actually warm decently into the low- to mid-40's, with increasing clouds during the morning and early afternoon.  As the energy from this system approaches the areas, we'll see the threat of some rain and snow showers to spark up across the region.

Timing and What?    

    The chance of precipitation is most likely between 3pm and 11pm Tuesday.  The late afternoon before sunset will be the best threat for a rain/snow mix, but as the cold air rushes in around sunset, any precipitation falling likely comes down in the form of a flurry/snow shower or even a heavier squall in some spots.  Though pavement accumulation isn't likely due to the 'warmth' during the day (and even a little bit of possible sunshine), unpaved surfaces will cool off much more quickly and give the best chance of any accumulation with the scattered precipitation.

Where and How Much?

    The best accumulation threat is the further north and west you go, where the most energy and colder air will be.  Therefore, North Jersey holds the best chance of a coating to 1" on all surfaces (even 1"+ in heavier squalls).  Then, heading into Central and South Jersey, the showers will be a bit more scattered, leaving a trace to coating threat, with even upward of a few tenths of an inch.  Though, the best possibilities of this the further north you are.  These accumulations would likely be more confined to grassy and unpaved surfaces due to slightly warmer temperatures.  Finally, the extreme southern parts of the state will see the best chance of just a trace of snow, likely not accumulating on average with a better chance of liquid precipitation.  

Reminder: A "trace" is anywhere from one flake of snow to less than 0.1"

My 1/12/16 Snow Map

Winter's Back! ...After This Weekend Ends

    Winter is finally back to start 2016, following a December that obliterated records due to warm temperatures!  The atmospheric pattern has finally become more favorable for cold and winter storm potential, so I hope that you didn't think it'd be gone for good, especially since spring doesn't start for more than two months.  However, through tomorrow, it will actually feel a bit like spring due to a combination of mild temperatures and rain.  Following tomorrow though, cold air and snowflakes are fair game.

    As a decent low pressure system pushes north through the Ohio Valley tomorrow, a southerly flow out ahead of it will provide us with highs of ~25° above average, possibly breaking records.  Philadelphia's record high tomorrow is just 63°, and we'll likely reach into the mid-60's.  Accompanying this warmth will be a nice shot of rain, which will mainly begin after midnight tonight and last through mid-day tomorrow, with periods of steady rain (moderate to heavy at times).  In total, we'll likely see rainfall totals of around 1" through tomorrow evening.  Winds will also be a further impact, as we'll see them sustained at 10-25 mph through tomorrow night, with gusts to 40 mph possible.  Below is simulated radar for 4am early Sunday morning:

12z NAM simulated radar at 4am Sunday morning (tropicaltidbits.com)

    One possible concern would be for Sunday night/early Monday morning, when lows drop below freezing, which would provide for any remaining wet spots to freeze over following tomorrow's rainfall.  In addition, behind tomorrow's system, a trough will dive into the Northeast, bringing winter-like cold back to the region.  Highs will regress back into the 30's/low-40's throughout the week, with lows into the teens/20's.  Breezy conditions will continue Monday through Thursday, which will help make it feel even colder than it already is.

    Finally, for now, we have a very minor snow threat to talk about!  A clipper will quickly dive out of Canada on Tuesday, bringing the possibility of flurries and scattered snow showers after the late afternoon and into the night.  Though it's nothing major and would likely do nothing more than coat the ground at worst, it would be a very welcome sign to snow-starved lovers of snowflakes (better idea as Tuesday gets closer of course).  Below, I'm even attaching this morning's NAM model run, showing some scattered snow showers toward sunset on Tuesday for our area:

12z NAM showing scattered snow showers for 4pm Tuesday (tropicaltidbits.com)