DAYS 1-5 (OCTOBER 1-5)
High pressure is going to be the main player in our weather with fair conditions for the next 5 days. But the first morning of October dawns with clouds mainly across Cape Cod and only a few fog patches across the landscape, so why is there so little sun? The answer: A Canadian wildfire smoke plume, a rather thick one, making the sun look silvery as it rises in the eastern sky through the smoke which sits mainly aloft but also somewhat closer to the surface as well. This plume, brought in by a light northeasterly air flow between departing low pressure and approaching high pressure, will thin from west to east during the day to allow for brighter sun with time. But the main smoke source being fires just south of Hudson Bay Canada and us seeing a northerly wind on Monday with high pressure centered to the west means additional smoke will filter into the region, both at the surface and aloft, again filtering the sun. High pressure slips to our south Tuesday, helping to clear the smoke and also making it a warmer day with 80 degrees not out of reach for some places. A weak frontal boundary will scoot through the region nearly unnoticed Tuesday night, other than the wind will shift to north at night and east Wednesday as a new high pressure area moves out of eastern Canada. There may still be some smoke to contend with heading into midweek but with some luck, the main fire areas in Canada will see a bout of rainfall to help reduce the fires by then (with a more helpful rain due there later this week). By Thursday, high pressure will be east of our region with a southeast to south breeze but still some very nice early autumn weather continuing.
TODAY: Early ground fog patches favoring interior low elevations and early to mid morning clouds on Cape Cod, otherwise smoke-filtered sunshine gradually becoming brighter. Highs 67-74. Wind NE up to 10 MPH.
TONIGHT: Clear. Fog patches low elevations. Smoke returns overnight. Lows 47-54. Wind N up to 10 MPH.
MONDAY: Sunny. Highs 69-76. Wind N up to 10 MPH.
MONDAY NIGHT: Clear. Ground fog patches interior lower elevations. Lows 47-54. Wind NW under 10 MPH.
TUESDAY: Sunny. Highs 75-82. Wind W up to 10 MPH.
TUESDAY NIGHT: Clear. Ground fog patches interior lower elevations. Lows 47-54. Wind N up to 10 MPH.
WEDNESDAY: Sunny. Highs 68-75, coolest coastal areas. Wind E up to 10 MPH.
WEDNESDAY NIGHT: Mostly clear. Fog patches again in lower elevation locations. Lows 48-55. Wind SE up to 10 MPH.
THURSDAY: Sun and a few clouds. Highs 70-77. Wind SE to S 5-15 MPH.
DAYS 6-10 (OCTOBER 6-10)
October 6-7 sees more humidity, more clouds, a southerly air flow, and eventually a period or two of rain showers with the approach and passage of a frontal system, but I don’t expect this to be a long lasting bout of unsettled weather as we get into a cool, breezy, dry air mass right after that, with a potential reinforcing cool shot on its heels for the end of the period. Details to be worked out…
DAYS 11-15 (OCTOBER 11-15)
High pressure controls the weather with another dry stretch for much of if not all of this period, starting cool followed by a milder trend.