Bermuda Weather Service Forecast Discussion

For Wednesday, December 07, 2022  10:00 UTC

FORECASTER - Anton Wiltshire 

Nowcast: Today/Tonight
Occasional showers moved through the area from the northeast with 
increased cloud cover that only lasted for the start of the night 
but then moved out to the southwest. The broad area of low pressure 
to the southeast remains distant from Bermuda but will continue to 
meander to the southeast before making its way to the northeast. 
As it meanders to the southeast, weak trough move through the area 
which will bring intermittent showers and there is good consensus 
between the global models. The NHC has increased the chance for the 
low to acquire subtropical or tropical characteristics to 50% in 
two days and 50% in five days but does not pose a threat to Bermuda. 
Winds at our AWOS stations began moderate to strong with gusts at 
times but quickly diminished light by midnight with a northerly direction. 
The latest GOES 16 visible satellite imagery shows small bands of 
cumulus moving through the area from the NE while the latest RADAR 
imagery shows weak echoes traversing the area producing isolated 
showers. Model analysis hints at cloud cover increase during the 
afternoon with a few showers possible. Winds today progged to be 
north northeasterly 16-22 knots increasing for a time 20-25 knots 
before easing 15-20 knots overnight. Gusty winds are likely in showers. 
Surface analysis at 06Z shows a dissipating frontal boundary nearby 
and a broad low pressure system to our southeast inducing troughing 
around the area. Latest OPC analysis has seas 9-12ft which has also 
initialized well with the global models and expect rough seas to 
reach near very rough by tonight.

Warnings: A Small Craft Warning remains in effect through tonight.

AVIATION:
VFR conditions should dominate through the period, however there 
is the chance conditions may drop to MVFR with showers that may move 
over the airfield today and may result in a wet runway. North northeasterly 
winds 16-22 knots veer northeasterly at times before decreasing 12-18 
knots overnight. No other aviation hazards are anticipated.  For 
more information visit: http://weather.bm/aviation/


SHORT TERM FORECAST: Thursday through Friday
Ridging at the surface positioned to the west of Bermuda is trying 
to establish itself near the island while a front is moving off the 
NE USA. Low pressure that develops to the north, drags the front 
through the area later Thursday into Friday before exiting later 
that day leaving drier conditions. Expect increased cloudiness with 
showers, but the chance for thunder isnít likely as indices remain 
low. The deepening low, which by this time could be a possible subtropical 
storm, is moving out to the northeast. Surface pressure close to 
1020mb on Thursday morning drops below 1010mb into Friday. Northerly 
winds 6-12 knots back near west by Thursday night. Winds then veer 
northwesterly and increase 15-20 knots by Friday morning in response 
to the tight isobars between the exiting low and high pressure to 
the west, possibly increasing 20-30 knots. In the upper level, ridging 
holds on Thursday with troughing to our east while a short wave trough 
to the north tries to dip closer to the area but remains north of 
Bermuda. QPFs are forecasted to register below 5mm over the short 
term period. Regarding seas, rough to very rough seas remain for 
the duration of the short term forecast. 

Warnings: A Small Craft Warning will be in effect for the short 
term period for rough seas. No other watches or warnings anticipated. 


LONG TERM FORECAST: Saturday through Sunday)
At the surface, the cold front that passed over us a day earlier 
lingers to the north and deepens into a broad area of low pressure 
that will introduce some cloudy weather around. Models are in better 
alignment with wind speeds over the weekend with winds forecasted 
to be northwest 18-24 knots possibly becoming 25-30 knots but would 
veer north on Sunday and ease 8-15 knots. Instability indices remain 
quite low hence the chance for thunder isnít likely. In the upper 
levels, broad upper troughing hangs around with axis to the east 
of the island placing Bermuda on the convergent side of the upper 
trough which would help inhibit any deep development of surface features. 
Over the two day period, QPFs are progged below 10mm over the 2 day 
period. Rough to very rough seas up to 14ft is likely through the 
long term period.

Warnings: The Small Craft Warning is expected to be extended through 
the long-term period. No other watches or warnings anticipated. 


TROPICAL:  Please refer to the latest Tropical Weather Outlook (TWO) 
courtesy of the National Hurricane Center (NHC) for more details 
via https://www.nhc.noaa.gov/