Tuesday May 18 2021 Forecast (7:15AM)

32 Comments

DAYS 1-5 (MAY 18-22)

A disturbance will cross the region from northwest to southeast today bringing some cloudiness especially this morning, and allowing for the development of a few isolated showers with the sun’s heating this afternoon. Upper level high pressure builds over the region with mainly dry weather at midweek. Look for sea breeze development both today and Wednesday. The wind may end up turning onshore more regionally during Thursday (timing uncertain) as a weak back door cold front moves into the region. There’s a little more uncertainty in the forecast for late week (Friday and Saturday) as the axis of the ridge is far enough west to allow a reinforcing back-door front into the region from the northeast and a couple disturbances to come through the region with chances for showers. There will be some fine-tuning needed on that part of the forecast.

TODAY: Variably cloudy. Isolated afternoon showers. Highs 73-80, coolest coast. Wind variable up to 10 MPH with coastal sea breezes developing.

TONIGHT: Clearing. Lows 50-57. Wind variable under 10 MPH.

WEDNESDAY: Mostly sunny. Highs 80-87 except 70s in some coastal locations and 60s on parts of Cape Cod and the Islands. Wind variable up to 10 MPH with coastal sea breezes developing.

WEDNESDAY NIGHT: Partly cloudy. Lows 55-62. Wind variable under 10 MPH.

THURSDAY: Partly sunny. Chance of a shower late in the day. Highs 77-84 but may turn considerably cooler at least in eastern coastal areas by late. Wind SW to variable 5-15 MPH possibly shifting to NE by later in the day especially in southeastern NH and eastern MA.

THURSDAY NIGHT: Variably cloudy. Possible showers. Lows 55-62. Wind variable to NE 5-15 MPH.

FRIDAY: Variably cloudy. Possible showers. Highs 63-70, coolest coast. Wind NE 5-15 MPH.

FRIDAY NIGHT: Variably cloudy. Possible showers. Lows 53-60. Wind variable 5-15 MPH.

SATURDAY: Variably cloudy. Possible showers. Highs 65-72, coolest coast. Wind variable 5-15 MPH.

DAYS 6-10 (MAY 23-27)

Frontal boundary likely in the region with possible showers and thunderstorms as higher humidity May 23. Front pushes to the south with cooler weather and potential rain due to a wave of low pressure May 24. Drier/cooler weather follows from high pressure in eastern Canada mid period then milder with possible unsettled weather again later in the period as the next disturbance approaches / arrives.

DAYS 11-15 (MAY 28 – JUNE 1)

Trends on medium range guidance say we sit in between warm high pressure to the south and cool high pressure in Canada and this leaves us vulnerable to shower activity and variable temperatures. Not a very high confidence forecast with re-evaluation to come.

32 thoughts on “Tuesday May 18 2021 Forecast (7:15AM)”

  13. Nice shower for the upper Cape and big dark cloud dropping big rain drops here in central Marshfield. I was hoping for a bit more as the hood of my car is covered in green.

  15. Hi everyone, looks like you all are getting into some of the warm weather.
    My apartment is about 1000 feet above sea level so I been enjoying high temperatures in the low 80s and night time temperatures in the low 70s as of late with a nice breeze. Lower elevations get into the higher 80s now this time of year. I hope the normal temperatures for the Virgin islands continue but I doubt it will. Only a matter of time for the humidity to pick up.

  16. This is a reason I try to get out and enjoy days like this with the humidity in check.

Comments are closed.