Flood Watch Posted for Friday/Saturday

After a record cold start to 2018, record high temperatures are likely tomorrow as a surge of warm, moist air accompanies a storm system to the Northeast.  The melting of the existing snowpack, along with the expected heavy rain, has prompted the National Weather Service to issue a *Flood Watch* for all of Southern New England.

NWS Boston Late AM Headlines

Urban street flooding appears to be the greatest threat but some rivers may also approach flood stage.  The warmth will be followed by a flash freeze on Saturday, creating hazardous travel for those heading to the Patriots game Saturday night.  There is the potential for a winter storm during the middle of next week.

General Overview

GOES 16 Upper Level Water Vapor Loop (image College of DuPage NEXLAB)

The storm system is pulling moisture from the Tropical East Pacific and the Gulf of Mexico as it tracks east across the Central US.  One low pressure center is tracking northeast into the Western Great Lakes.  This will be the main source of the rainfall tomorrow.  A second low will form along the Gulf Coast and track Northeast along the Appalachian Mountains.  This will bring the rainfall on Saturday AM.

WPC Surface Fronts/Precipitation Friday 7 AM

A strong Arctic high descending into the Central US will help keep this storm system moving.  It’s a good thing too as there is a lot of moisture to work with.  Some thunderstorms will be possible Friday evening in Southeastern New England during the afternoon/evening commute.

WPC Surface Fronts/Precipitation Friday 7 PM

A change to ice is possible Saturday AM as the second storm winds down.  The greatest impacts will be in Central, Northern, and Western New England.  Everyone will have to deal with a flash freeze but this will be much easier to deal with if there is not a glaze of ice on top of it.

WPC Surface Fronts/Precipitation Saturday 7 AM

Timing and Impacts

Temperatures overnight will only fall into the low to mid 40’s.  These will potentially surpass the record low minimum temperatures set last year in Worcester and Providence and in 2006 in Boston.  It will also help set the stage for record warmth Friday afternoon.

NDFD NWS Min Temperatures Thursday night into Friday (image Weatherbell)

It will be foggy tomorrow AM with some showers after 8 AM.   The showers will become more widespread and numerous after 1 PM and the heavy rain will arrive after 4 PM.  By 7 PM, it will be pouring across most of Central and Eastern Southern New England.

12z NAM hires Simulated Radar Friday 7 PM (image WeatherModels.com)

Max temperatures tomorrow afternoon will be near 60 in Boston and in the low 60’s across Bristol and Plymouth counties as well as most of Rhode Island.  In Central MA, temperatures will be in the upper 50’s.

NDFD NWS Max Temperatures Friday (image Weatherbell)

The rainfall intensity will let up for a bit after 11 PM in Worcester County but will continue to fall moderately to heavily across SE MA/RI.  Rainfall rates will increase again after 4 AM in the Worcester area and by 7 AM it will be pouring again.  The rain looks to clear out by 10 AM Saturday.

12z NAM Hires Simulated Radar Saturday 7 AM (image WeatherModels.com)

Although temperatures will be in the 50’s Saturday AM, a spectacular temperature crash will follow late morning into early afternoon.  It may be 50 at 7 AM and 25 by 1 PM in Worcester.  Road crews will need to be out as soon as the rain ends.  Unfortunately, the roads cannot be pretreated as the rainfall intensity will wash away the salt.  There will be black ice everywhere after the rain ends.

12z NAM hires 2 m temperatures Saturday 1 PM (image WeatherModels.com)

By 8 PM temperatures will be in the teens to low 20’s.  All in all, a widespread 2-4″ of rain will fall with highest totals in SE MA, the Cape, and Islands.  Localized totals over 4″ are possible here.

NDFD NWS Total Precipitation through Saturday 7 PM (image Weatherbell)

Wind headlines will also be needed across SE MA, the Cape, and Islands.  Wind gusts tomorrow afternoon of 40-50 MPH are likely with stronger gusts possible Saturday AM as the stronger Southern low tracks through Southern New England.  Back in Worcester and Central MA, wind gusts tomorrow afternoon of 30-40 MPH are possible but the lingering snowpack will limit the wind potential.  Stronger winds are possible Saturday AM if a lot of the snow disappears Friday and the low tracks through Western New England.

River forecast Blackstone River @ Northbridge

As of right now, the forecast calls for the Blackstone River to stay below Flood Stage.  This forecast almost always is underdone.  While I don’t expect major or even moderate flooding, the Blackstone will likely approach 8-9 feet Saturday afternoon.  Low lying homes and businesses along the river should be prepared to get some water near their property.  You can track your local river here.  This is a fairly anomalous weather event for early to mid-January.  I’ll have another update tomorrow AM with the latest radar/satellite trends.

Next Week

We will return to below normal temperatures on Sunday and Monday, but nothing like we saw the last week of December and the first week of January.  A potential winter storm will track close enough to the region Tuesday PM into Wednesday AM to bring precipitation.  My feeling is this will be a snow event but its too soon to say.  It’s also possible the low tracks over Southern New England changing precipitation from to snow to mix to plain rain.

WPC Forecast Fronts Wednesday 7 AM

There should be plenty of moisture to work with so stay tuned.  If the track is right, a moderate snow event is possible.  This is my project for the weekend once all the fun and games end on Saturday.

-Zack Green

Leave a Reply