Plain-language summary:
It will be incredibly dry and quiet
weather-wise for the upcoming week and possibly through the middle of the following week. The remnants of Ophelia
will bring cloudy but mostly dry weather from the southern Adirondacks to
southern Maine today, but it will stay sunnier to the north. Northeasterly
winds will bring slightly cooler temperatures Monday and Tuesday, especially north
of the U.S./Canada border, but winds will weaken and it will gradually warm up
for the rest of the week, staying remarkably sunny and dry. Daytime highs may
approach or break daily records by the end of next week or early the following
week, but it will not be truly hot given that it will be the end of September.
Meteorological discussion:
This will be a short blog post, as we
just have a broad high pressure dominating eastern Canada and northern New
England for the entire upcoming week! The remnants of Ophelia will bring cloudy but
mostly dry weather from the southern Adirondacks to southern Maine today, while
areas farther north will see mostly sunny conditions with just some high cirrostratus or cirrus. The remnants of Ophelia
will weaken and pass by to the south today into tomorrow as the broad high
pressure gradually builds in from the northwest, so even southern areas will
clear out by late tomorrow. The northeasterly winds will initially bring slightly cooler
temperatures for Monday and Tuesday, especially north of the U.S./Canada border,
but the air mass is not that cool. Eventually, the wind will weaken and
temperatures will slowly warm with clear skies and no rain. If this were
summer, a heat wave would quickly build in, but the much lower sun angle and
longer nights, now that we are past the autumn equinox, will limit how warm it
gets. Nights will be a bit cool outside urban areas with the clear skies and
light winds. There will be remarkably little day-to-day variation, in stark
contrast to the roller-coaster weather often seen outside of summer.
 |
| Source: Penn State Meteorology |
 |
| Source: TropicalTidbits |
With the lack of rain after this past Tuesday
and none expected this week, the ground will gradually dry out with sunshine
every day, even if the sun is weaker than in summer. The air mass will also be a bit dry, coming out of central and eastern Canada. The pattern across North
America will be incredibly stagnant even through at least early the following
week, with repeated troughs entering western North America and an almost
stationary strong upper-level ridge encompassing eastern Canada, centered
around James Bay. This is associated with a -PNA building and an NAO settling to near zero. There will continue to be a slow-moving cut-off upper-level low in the western
Atlantic, underneath the eastern Canada ridge, but it will very likely be too far south to bring much if any clouds and rain to our
region. With the ground drying out, more of the sun’s energy going into heating
the ground, and no cool air masses entering the region, daytime temperatures
could reach 77F (25C) or higher in lower elevations by next weekend or early
the following week, approaching or breaking daily records, though falling short
of the historic late September 2017 heat wave. Some October monthly record highs could be in jeopardy if everything goes right. The warmth could slow the
progression of fall foliage a bit, though the cooler nights should prevent it
from being stifled completely.
 |
| Source: TropicalTidbits |
 |
| Source: Climate Prediction Center |