Surges of Rain This Morning

A slow moving cold front which brought severe weather to the western parts of New England yesterday will finally push across the region today.  We were able to break the heat yesterday and today we will break the humidity.  There is a trade off; multiple bouts of rain will move across Southern New England this morning.  Already there has been heavy rain with embedded thunder and lightning over the Cape.  There has been a lull in Southern Worcester County but this will fill in during the next hour or two.

NWS Northeast Regional Radar 538 am

This rain has tropical connections.  Here is the water vapor satellite image with the surface fronts super imposed.

GOES_East Water Vapor Satellite 515 am

We can also look at the precipitable water which measures the heavy rainfall potential

SPC Precipitable Water 5 am

With values up around 1.7 and 1.8 inches there is a high chance for urban flooding if one of these waves sit over the same area for an extended period of time.  Western MA, Western CT, an SE MA are most likely to see this.  Here is the radar estimated rainfall total since noon yesterday

NWS Boston radar precipitation estimate 6/02/13 12 PM-present

That's nearly 3 inches near Springfield with more to come today.  Here are the temperatures this morning

2 m temps 5 am (image weatherbell)

Here is a look at the dew points

2 m Dew Points 5 am (image NCEP)

This combination will result in sticky conditions and of course rain as temperatures and dew points are about the same.  

Short Term Forecast

Rain will continue to work northeastward as the cold front pushes towards the coast.  The front may get hung up over the CT/RI border and through Worcester County.  This will keep SE MA in the rain for most of the day.  Nantucket and Martha's Vineyard will see storms work in off the Atlantic

WPC surface forecast 2 pm Monday

Here is the simulated radar for 2 PM

06z NAM hires simulated radar 2 PM (image weatherbell)

The tropical connection will continue to send waves along the front.  With it stalling out in Central New England that leaves Eastern MA under the fire hose.  Temperatures at 2 PM

06z NAM hires 2 m temp 2 pm (image weatherbell)

It should get to 70 in Eastern MA.  Most of us stay in the 60's, but it is a sticky feeling.  So how much additional rainfall to expect?  Here is the WPC day 1 outlook

WPC Day 1 Precip Outlook 

In general another 0.3-0.7 inches but I think isolated areas over the Cape may see over an inch.  The good news is that this front is going to be offshore by tomorrow morning.  Overnight lows will drop into the upper 40's across Southwestern New England and will be near 50 in Southeastern New England.  Here is the forecast surface chart

WPC surface forecast 8 am Tues

High pressure over the Great Lakes will introduce a Northwesterly flow into the region.  Tomorrow is dry, the humidity is low, and temperatures are in the upper 60' to low 70's.

06z NAM hires 2  m temp 5 pm Tues (image weatherbell)

Lows tomorrow night will be in the low 50's for everyone except those in the Berkshires; there we can expect temperatures in the low to mid 40's.  On Wednesday it will be warmer with temperatures in the mid 70's.  

Tropical Update

Hurricane Season officially began on Saturday and will run through November.  There is something to monitor in the Gulf of Mexico near the Yucatan.  

NHC Atlantic basin outlook

There is a low chance (20 %) of this system developing in the next 48 hours.  Guidance is sensing development but it should be fairly weak and slow to occur.  It is possible that something subtropical emerges on the east coast of Florida and tries to run the Eastern Seaboard at the end of the week.  I'm not really worried about wind but I am about more heavy rain moving into the area.  If named it will be Andrea

WPC Day 5 surface forecast

For the week the WPC is predicting almost 3 inches of rain in Southern New England

WPC 7 day precip outlook

Have a good Monday.