[Weather] NWS Boston EM Briefing: Rain and Accumulating Snow Hazards Through Wednesday

[BOX Operations - NOAA Service Account]

Good Morning,

This is an update to yesterday afternoon's email on potential weather
hazards today through Wednesday. Overall, little has changed aside from a
slight increase in snowfall amounts Wednesday.

We have attached forecast graphics of rainfall totals through tonight as
well as snow accumulations and an approximate rain-to-snow changeover time
for Tuesday Night and Wednesday.

*Today and Tonight: Rain (Heavy at Times)*

Heavy rain later today and tonight will bring rainfall totals of 1 to 2
inches to much of southern New England with possibly as much as 3 inches in
a few locations near the South Coast. In addition, unseasonably mild
temperatures in the 50s will lead to significant snow melt.

The combination of rain and snowmelt is not forecast to result in flooding
of rivers or streams. However, minor urban and poor drainage nuisance
flooding is possible especially where storm drains are clogged. Areas of
standing water from rain and snowmelt will affect the evening commute.

*Confidence:* High. Heaviest rains are expected to the south of where
snowpack is greatest, and it would take heavier rainfall further to the
north to produce a greater flood threat, which is unlikely at this time.

*Tuesday Night into Wednesday*: *Accumulating Snow*

Rain will change to snow late Tuesday night into Wednesday morning. Snow is
expected to end by Wednesday afternoon.

Much of southern New England should see a plowable snowfall, with the
exception of Cape Cod and the Islands and perhaps the immediate South
Coast. As temperatures fall during the night, wet pavement may freeze and
become slick. This may result in slow travel into the Wednesday morning
commute.

*Confidence: *Moderate. The axis of heaviest snowfall remains in question,
which could alter snowfall totals (up or down) on the northwestern or
southeastern end. Changeover timing is approximate and will depend on how
quickly colder air advances southeast.

**Note:* Please consider the snow accumulation and onset time graphics as
*preliminary* and are subject to further adjustments.

Meteorologists: Joe DelliCarpini and Eleanor Vallier-Talbot

If you have any questions or would like more information, don't hesitate to
contact us via this email address, on NWSChat <https://nwschat.weather.gov/>,
or at the following:

National Weather Service Boston/Norton, MA
46 Commerce Way
Norton, MA 02766
508.622.3280
Website <http://www.weather.gov/boston> | Facebook
<http://www.facebook.com/NWSBoston> | Twitter
<http://www.twitter.com/NWSBoston>
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