Bermuda Weather Service Forecast Discussion
For Thursday, March 23, 2023
08:00 UTC
FORECASTER - Troy Anderson
Nowcast (Thursday)
Overnight, partly cloudy skies continued as low-level moisture from
the east caused a few light showers to drift into the area. Light
to moderate northeasterly winds veered towards the east and eventually
southeast. A few light showers passed through the area from the east
during the evening before exiting overnight.
The latest GOES 16 IR imagery shows Bermuda within few to scattered
amounts of maritime stratocumulus clouds and under thin upper cirrus
spilling over from the west. The latest RADAR imagery remains clear
and echo-free in our immediate area. In the upper-level outlook,
Bermuda moves to the backside of a broad upper trough with a strong
upper ridge moving in from the west. This will help encourage the
suppression of surface development from aloft through the day. Near
the surface, a ridge of high pressure is due to move from our north
to our northeast and eventually east. This will move Bermuda towards
the western flank of the ridge maintaining the settled regime and
allowing plenty of sunshine for the day. Light to moderate easterly
winds begin the day before veering towards the southeast and south
overnight.
Cloud cover within the NWP suite remains variable today but diminishes
during the afternoon. QPFs remain near 0 mm and a rather dry day
is anticipated. A few partly cloudy spells are likely during the
day as Bermuda transitions towards the western flank of the high.
Wind data eases and veers winds from the E towards the SSE. Global
models continue to align quite well with the pattern and moderate
to high confidence exists. Temperatures begin to rebound slightly
under the traversing high. Ranges increase towards the mid-to-upper-60s
and minimums falling towards the mid-to-low 60s (F). With the passage
of low-level cloud cover, easing and veering east to southeasterly
flow, and WAA, temperatures will likely reach the expected high of
66F (+/- a degree or so). The UK and GFS wave models continue to
reduce states from the 6-8-foot range through the day and moderate
seas are slated to persist. The latest OPC analysis shows 6-8-foot
seas offshore within our area with the expectation for heights to
gradually fall. With all forecast parameters below the watch and
warning criteria, no watches or warnings are anticipated for the
nowcast period.
Aviation: VFR conditions begin the period at TXKF as light to moderate
winds near 08-12 knots from 080-100 degrees veer towards southeast
and ease towards the 5-8 knot range. RWY 12 will likely be active.
For more information, please see www.weather.bm/aviation
Short-Term (Friday- Saturday)
During the short term period, strong upper ridge moves in from the
west and maintains the suppressive forcing from aloft through the
period. This will continue to suppress surface development through
the period. Near the surface, high pressure will weak slightly as
the center of the ridge moves off to the distant east and a low pressure
to the distant northwest moves into the Atlantic. This will move
Bermuda south of the warm sector of the passing low pressure system
through Friday. Then on Saturday, while the first low moves to the
northeast, a second low will near the US northeast coast. A boundary
is due to link the two and this feature will begin to sink down towards
the Island. Global models keep the regime quite dry as Bermuda transitions
from warm sector to warm sector. Wind data swings winds around to
the southwest and increases speeds later on Saturday towards the
upper bounds of the moderate criteria. There exists a brief window
for winds to become moderate to strong from the evening and overnight
periods, especially as the boundary creeps closer and closer. Then
on Saturday, winds veer towards the west and then begin to ease.
A good mix of sun and clouds will continue through the short term
period with increases to cloud cover during the nights. The UK and
GFS wave models both hold moderate states through the period with
heights 4-6 feet on Friday and 5-8-feet on Saturday. A Small Craft
Warning becomes likely from Friday evening and lasts through the
night. Thereafter, no other watches or warnings are anticipated.
Long term (Sunday- Monday)
Then on Sunday, Bermuda slips into the second warm sector of the
low moving from the northwest to our north. This pattern looks to
increase winds out of the WSW and SW becoming moderate once again
within the 12-18 knot range. Temperatures continue to gradually increase
pushing into the 70s F and low nearing the mid-60s. A boundary will
descend from the north and graze the area from the north. The consensus
within the global models keeps the boundary outside of the area to
the north before the stalling. Then, another low moving into the
Atlantic from the northwest will merge with the moisture to the north
and is expected to lift northward. A warm front will help bring rain
and showers nearby overnight. Concerning seas, states and heights
fall remain below the 9-foot threshold and are expected to fluctuate
within the 5-8-foot range. No watches or warnings are anticipated
for the long term period.