Bermuda Weather Service Forecast Discussion

For Friday, January 28, 2022  10:00 UTC

FORECASTER - Duty Forecaster 

Nowcast (Friday)
Mostly cloudy skies and patchy rain continued overnight as a frontal 
boundary sagged over the area. Moderate to strong northeasterly winds 
persisted through the overnight period before easing. The latest 
GOES 16 IR satellite imagery kept Bermuda under the rather extensive 
cloud cover of the frontal mass. The latest RADAR imagery shows batches 
of rain and embedded showers passing overhead from the west with 
gaps within the flow. In the upper level analysis, Bermuda begins 
the period near zonal flow and south of a broad upper trough. The 
latest surface analysis shows a frontal boundary to our south meandering 
nearby. This pattern remains quite neutral in upper support with 
upper troughing in the north but upper ridging in the south and east. 
Expect the gradual drift of the frontal boundary northward back into 
our area. Global models retrograde the front before beginning to 
merge its moisture with a developing low pressure near the Florida 
coast.

Expect the retrogression and then passage of a warm front over the 
island through Friday. The developing low to the west will take some 
time to begin the process and thus, there may be a delay in the return 
of persistent rain and showers. Thus, some sunny intervals are possible, 
especially during the afternoon. Spotty showers and patchy rain will 
begin to ease during the morning decreasing frequency and intensity 
before picking up towards the evening. Global models carry low QPF 
values during the day before increasing values towards the evening 
and overnight portions. There continues to be a push for spotty and 
light precipitation during the day. Concerning winds, wind data within 
the suite veers winds from the northeast towards the east and eventually 
southeast. Mean speeds increase from the afternoon becoming moderate 
to strong between the 14-22 knot range just before evening. Winds 
then continue to ramp up overnight becoming 20-30 knots with the 
potential for gale force gusts. There only remains slight divergence 
in mean speeds and models continue to be in decent alignment. Confidence 
in the nowcast remains moderate to high. Expect a few sunnier periods 
during the day as the warm front and depression organize and then 
anticipate the return of the wet and damp regime from the evening 
as winds begin to strengthen. The latest OPC wave analysis maintains 
6-8-foot seas in our area with the expectation of states to increase 
towards to the rough criteria through the period. Due to the expected 
wind increase and anticipated rise of sea states, a Small Craft Warning 
come into effect from the afternoon ahead of the evening hours. MOS 
and other temperature maintain cool temperatures ranging between 
67F and 61F. With rather copious amounts of mid-to-upper cloud cover 
expected, the increasing wind regime, and transition to WAA, this 
will likely be the case perhaps +/- 1 or 2 degrees. 

Aviation: Mainly VFR conditions start the period at TXKF as mainly 
light to moderate winds near 08- 12 knots from 050 degrees veer towards 
the east and increase through the day. Patchy rain and showers begin 
to subside through the day before increasing from the evening bringing 
the potential for MVFR conditions. For more information please see 
www.weather.bm/aviation. 

Short-Term (Saturday- Sunday) 
Saturday features as the highlight of the weekend as winds quickly 
ramp up ahead of a vigorous cold front. In the upper level analysis, 
Bermuda finds itself under the influence of an approaching and deepening 
upper trough with much vertical extend. Global models sharpen and 
dig this trough as it approaches from the west. By Sunday, an upper 
low will develop near the northeast coast. This pattern looks to 
enhance the development of surface conditions. Near the surface, 
expect the passage of the warm front overnight Friday into Saturday 
morning. Shortly after, the NWP suite transitions Bermuda into the 
warm sector of a deepening depression as it quickly travels up the 
eastern coast of the US. Global models rapidly reduce central pressures 
beginning near 1000 hPa on Saturday morning before nearing 970 hPa 
just 18-24 hours later. It should be noted that there still remains 
slight disagreement as to the magnitude and intensity of the low 
but bombogenesis remain likely. Locally, the Island and marine area 
will adopt southerly winds increasing 20-30 knots during the early 
morning hours before increasing towards the 30-38 knot range during 
the afternoon and evening. BL winds have recently extended the range 
towards the 50-65 knot range with gusts likely into the storm force 
category. The top end for wind gusts continues to push towards hurricane 
force though this potential remains less likely. The bulk of activity 
and heaviest precipitation is expected after 15Z/ 11AM local into 
the evening and night before beginning to ease towards Sunday. With 
the upper support, increasing instability, rapidly developing low, 
and increase of moisture, the potential for thunderstorm development 
remains fairly likely and a Thunderstorm Advisory may be warranted. 
A Gale Warning has been issued today valid from Saturday morning 
as winds ramp up. The UK and GFS wave models increase states rough 
to near very rough 10-15 feet from Saturday. Then expect the clearance 
of the front overnight into Sunday. Wind data within the suite eases 
speeds from the 20-30 knot range towards the moderate criteria. There 
exists the potential for a drier wedge behind the front allowing 
the easing of wet conditions overnight. Soon, a trailing trough brings 
cold air Scu cloud cover with embedded showers into Sunday.  Directionally, 
winds veer and settle out of the west and eventually northwest. Expect 
a rather cloudy Sunday with brisk, fast-moving showers.

Long term (Monday- Tuesday)
Then on Monday, the solid deck of Scu will remain as winds continue 
to ease and settle northerly. This pattern will continue to feed 
the persistent cloud cover before winds back towards the west and 
begin to reduce the incoming moisture. This will allow the gradual 
breaking up of cloud cover and easing of shower activity. Thermodynamic 
analysis brings the 540-thickness line nearby to our west. This may 
aid the blustery nature of the lingering shower activity. Then on 
Tuesday, lingering moisture to the northwest is expected to begin 
to organize and a low is likely to form. Global models slowly develop 
this weak low perhaps introducing cloudy periods overnight. A rather 
bright and dry trend takes hold of the island into Tuesday which 
remains the most settled day of the forecast period. Wind data keeps 
the northerly regime through much of Tuesday before tending to settle 
out of the west-northwest. Concerning seas, the UK and GFS wave models 
allow heights to fall through the period exiting the Small Craft 
criteria later on Monday and becoming moderate thereafter. Confidence 
for the long term period remains moderate.