Potential Winter Storm 12/11/19 – Winter Weather Advisory

A brief but potent Winter Storm may affect Southeastern New England on beginning Wednesday morning.  The National Weather Service Office in Boston has issued a Winter Weather Advisory for our area, and we have posted their snow accumulation map as the featured image:

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WWUS41 KBOX 101543
WSWBOX

URGENT – WINTER WEATHER MESSAGE
National Weather Service Boston/Norton MA
1043 AM EST Tue Dec 10 2019

CTZ002>004-MAZ012-013-015>022-RIZ001>007-102345-
/O.CON.KBOX.WW.Y.0026.191211T0300Z-191211T1700Z/
Hartford CT-Tolland CT-Windham CT-Southern Worcester MA-
Western Norfolk MA-Suffolk MA-Eastern Norfolk MA-
Northern Bristol MA-Western Plymouth MA-Eastern Plymouth MA-
Southern Bristol MA-Southern Plymouth MA-Barnstable MA-
Northwest Providence RI-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-Bristol RI-Washington RI-Newport RI-
Including the cities of Hartford, Windsor Locks, Union, Vernon,
Putnam, Willimantic, Milford, Worcester, Foxborough, Norwood,
Boston, Quincy, Taunton, Brockton, Plymouth, Fall River,
New Bedford, Mattapoisett, Chatham, Falmouth, Provincetown,
Foster, Smithfield, Providence, Coventry, West Greenwich,
East Greenwich, Warwick, West Warwick, Bristol, Narragansett,
Westerly, and Newport
1043 AM EST Tue Dec 10 2019

…WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 10 PM THIS
EVENING TO NOON EST WEDNESDAY…

* WHAT…Snow expected. Total snow accumulations of 1 to 4
inches.

* WHERE…Portions of northern Connecticut, south central and
portions of eastern Massachusetts as well as Rhode Island.

* WHEN…From 10 PM this evening to noon EST Wednesday.

* IMPACTS…Plan on slippery road conditions. The hazardous
conditions could impact the morning commute.

* ADDITIONAL DETAILS…Rain changes to snow from northwest to
southeast between 10 pm tonight and 4 am Wednesday, but that
process may not happen until near daybreak across portions of
the Cape. Biggest concern is the Wednesday morning commute,
especially across Rhode Island and southeast Massachusetts.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

Slow down and use caution while traveling.

A cold front will push the warm and rainy conditions currently affecting us out to sea.  Behind it, cold northwest winds will cool things down quickly, but a small storm will develop along the frontal boundary as it exits our area.

ref1km_ptype.us_ne

This will be a storm with only minor total accumulations.  However, given that it may be snowing during rush hour, expect delays and slippery driving conditions on Wednesday morning.  It will be a tough call for administrators on school cancellations on Wednesday morning, since the heaviest precipitation will be falling during the hours of 4AM – 10AM.

1-3″ is expected in most locations, but 2-4″ could fall in a few spots, especially south and east of Providence, based on the track of the storm along the front.  Dry air will limit snowfall as you get farther northwest.  Snow should end by late afternoon.  It will be cold and blustery Wednesday night into Thursday.

This post will be updated as needed.

 

 

12/1/19 – 12/3/19 Winter Storm Update Sun. 3:00 PM

Some slight changes to the forecast. The storm is starting later here in RI and SE MA, and will be extending later into Tuesday than previously forecasted. Snow is moving into RI right now, and should be in SE MA by 4-5 PM.

No major changes to my map right now, but it would not surprise me that it would need to be adjusted upward. Several models have forecasted more snow for RI and SE MA during “part 2″ of this storm, from the period of Monday evening into Tuesday. Areas north of Providence may see closer to 12″, and areas south of Providence, away from the coast may see 6-12”. Hard to say that scenario happens just yet because the part of the storm hasn’t formed yet.

Another update later this evening. Don’t be surprised when you watch the evening news tonight, they are predicting more snow than they were over the previous two days.

12/1/19 – 12/3/19 Winter Storm Update Sat. 1:30 PM

Forecast models continue to trend towards a winter storm with accumulating snow for the period of Sunday 12/1/19 through Tuesday 12/3/19.

The National Weather Service has updated their predicted snowfall map and amounts have trended upwards.

NWS-BOX-Storm20191201-Upd201911300420
Latest NWS Boston Snowfall forecast – Issued 11/30/19 4:30 AM.

What many consider the most accurate forecast model for winter storms affecting the east coast of the US, the European, continues to forecast 6-12″ north of Providence, 3-6″ south of Providence, and 1-2″ at the south coast.  The Cape and Islands will most likely be too warm for any measurable snow thanks to warm air mixing in. Highest amounts will fall in upstate New York, Northern Massachusetts, and Southern New Hampshire, Vermont, and Maine.

ECMWF Snowfall Forecast 2019-11-30-1200
European model snowfall forecast for Northeastern US. Courtesy of Pivotal Weather.

So far our first call map looks on track for RI and SE MA, with no need to update.  We will post another update later this evening,

PLEASE NOTE: All weather posts are my thoughts and opinions only.  These are not official forecasts, as I am not a trained meteorologist. Check local media outlets or the National Weather Service for official weather forecasts for your local area.  Weather posts are focused on Southeastern New England.

 

12/1/19 – 12/3/19 Winter Storm First Thoughts

PLEASE NOTE: All weather posts are my thoughts and opinions only.  These are not official forecasts, as I am not a trained meteorologist. Check local media outlets or the National Weather Service for official weather forecasts for your local area.  Weather posts are focused on Southeastern New England.

Meteorological winter begins this Sunday, and with the beginning of winter comes our first chance of measurable, and possibly significant, snowfall in Southeastern New England.

A large storm system currently located in the Rocky Mountains will move east across the country towards the upper midwest over the next few days.

prateptype_cat_ecmwf.conus
Storm system currently located over Rocky Mountains on 11/29/19. European model image courtesy of Pivotal Weather.

By Sunday, the storm will be located in the Great Lakes.  Strong high pressure north of the storm will continue to push cold air south from Canada into New England, laying the foundation for some frozen precipitation to occur.

prateptype_cat_ecmwf.conus-2
Storm over Great Lakes Sunday morning. European model image courtesy of Pivotal Weather.

As the storm runs into the blocking high pressure in Canada, it will transfer its energy to a second area of low pressure off the mid-Atlantic coast and strengthen to the south of New England.  The storm will then slowly move east-northeast along the Southern New England coast.

prateptype_cat_ecmwf.conus-3
Storm transferring to the coast and re-strengthening late Sunday/early Monday. European model image courtesy of Pivotal Weather.
prateptype_cat_ecmwf.us_ne
Storm strengthening south of New England Monday morning 12/2. European model image courtesy of Pivotal Weather.

The forecasted storm track is not favorable for a significant amount of snow in Southeastern New England – we do best when storms track just to the southeast of Nantucket.  Ocean temperatures are still mild, and the location of the storm will allow for warmer air to push in from the southeast, changing any snow into sleet and rain, before changing back to snow.  A lot could still change within the next 48 hours, as movement of this storm in either direction can make a big difference in snowfall amounts over a large portion of the area.  In addition, the storm reforming south of New England will also cause it to slow down, and it will not be moving northeast our of the area until Tuesday afternoon.

My “First call” snowfall map:

WeatherMap2019_20191201Storm
12/1/19 – 12/3/19 “First Call” snowfall map.

The best chances for significant snow will be north and west of a line stretching from approximately New Haven, CT, through Providence, RI, an up to Plymouth, MA.  For areas seeing significant snow, some will fall Sunday night into Monday, followed by a lull where snow may change over to a mix of sleet, rain, and freezing rain.  As the storm moves east, cold air will be drawn back in from Canada, and most areas will turn back over to snow through Tuesday morning.

Winter Storm Watches have been posted by the National Weather Service for most of Massachusetts and Connecticut in areas that will most likely be all snow.

Screen Shot 2019-11-29 at 11.19.44 PM
NWS Boston Watches, Warnings, and Advisories.

We will post again closer to the onset of the storm.  Stay tuned!