Weather with Bill Evans
Good Day On This Thursday March 4, 2021
The region will remain between strong low pressure over the Canadian
Maritimes and high pressure situated over southern Canada and the
Upper Midwest through the start of the weekend. The high will build
over the region Sunday and remain in control Monday and Tuesday, and
then shift to the south and east into the middle of next week.
The region will be under deep NW flow due to strong low
pressure stalled across far eastern Canada. This will result in
an enhanced pressure gradient over the area. With cold air
advection increasing over the region today expect gusty NW winds
to develop. This will be noticeable for the afternoon and
evening hours. With only a narrow layer of higher RH around 4 to
5 kft for today, expect a good deal of sunshine overall. 850 mb
temps towards days end get to -10 to -12 C. Therefore
temperatures for today should average a few degrees below
average due to the strong CAA despite sunshine.
With vertically stacked low pressure to our north and northeast our
area will remain in deep layered NW cyclonic flow. Lobes of energy
will rotate around the low. A mid level disturbance will pivot
through, or just NE of the area early tonight. This should only lead
to a few hours of cloudiness, otherwise it remains dry as the lower
levels will be moisture starved. The winds will stay up tonight on a
NW flow. Due to continued CAA temperatures will average below normal
tonight by about 10 degrees or so. Temperatures should be fairly
uniform, with the winds staying up precluding radiational
effects. Single digit and lower teen wind chills are on tap for
early Friday morning.
For Friday the stretch of dry weather will continue with the NW flow
also going nowhere. Min RH values are expected to be at or below 30
percent across the majority of the area, so subsequent shifts may
need to evaluate for any fire wx related statements. The main story
is the chilly, blustery and dry weather that will continue to close
out the week.
A deep and anomalous upper low will remain nearly stationary
over the Canadian maritimes Friday night into much of the
weekend. This upper low carves out a mean trough over the
eastern seaboard and western Atlantic. Ensemble means all
generally agree that the upper low begins to weaken on Sunday
before it lifts out into the north Atlantic into Monday. The
position of the upper low will hold upper ridging across the
Rockies/Great Plains and up into Central Canada. The ridging
only slowly shifts eastward on Sunday as the upper low weakens.
The aforementioned pattern supports dry and unseasonably cold
conditions Friday night through the weekend. The Tri-State area
will be sandwiched between the low pressure over the Canadian
Maritimes and high pressure to our west. A deep layered NW flow
will persist during this time ushering cold and dry air into the
region. High temperatures will generally be in the lower and
mid 30s for most locations, with the NYC metro slightly higher
in the mid and upper 30s, close to 10 degrees below normal.
Nighttime temperatures will be in the upper teens and lower 20s
inland, to the lower and mid 20s most elsewhere. The strongest
pressure gradient is currently progged on Friday night, with
gusts up to 30 mph possible, making it feel like it is in the
upper single digits and teens. While it will remain brisk on
Saturday, the pressure gradient is weaker and winds may gust to
around 20 mph. The surface high builds closer on Sunday, but the
core of the high is likely to not move overhead until Sunday
night.
The trough carved out by the deep low to our northeast finally
shifts offshore late Sunday into Sunday night. Heights aloft
will rise significantly Sunday night into early next week. An
initial ridge axis shifts through on Monday, followed by a warm
front passage on Tuesday, with high pressure settling to our
south. The overall pattern evolution supports a significant
warming trend next week, with temperatures possibly approaching
60 degrees away from the immediate coastline. Not ready to boost
temperatures higher than consensus blends right now due to the
time range. However, if trends continue, temperatures may need
to be raised farther away from the coast.
.MARINE...
Small craft conditions develop into this afternoon across all the
coastal waters with a strengthening pressure gradient developing. NW
winds will persist through tonight and into the day on Friday, with
SCA conditions continuing. There may be a few occasional gusts near
34 kts on the ocean for late this afternoon and tonight, but Gale
conditions are not anticipated at this time.
The pressure gradient begins to relax thereafter, with lingering SCA
conds on all but the Harbor and W Sound gradually easing towards
Friday evening. While wind gusts up to 20 kt are possible this
weekend, conditions are expected to remain below SCA levels.
Relatively tranquil conditions are forecast on Monday with high
pressure settling over the waters.
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