Bermuda Weather Service Forecast Discussion

For Wednesday, August 05, 2020  08:00 UTC

FORECASTER - Michelle Pitcher 

Forecast Discussion		Michelle Pitcher			5-Aug-20

NOWCAST (Wednesday)
Skies remained partly cloudy to mostly clear overnight as easterly 
winds remained around 10 knots.  Upper ridging remains over the area 
today, maintaining the surface high pressure.  Current settled and 
dry conditions are expected to continue through today.  Winds will 
remain easterly, light to moderate and no precipitation is expected. 
 Seas remain mainly slight (2-4 feet) outside the reefs.  The first 
of a couple of troughs is approaching the area from the south today, 
associated with the area of low pressure to our west that the NHC 
has been watching for the past several days.  The likelihood of this 
developing is very low now and details can be found in the tropical 
update section below.  The only real influence we see from this first 
trough is winds increasing 10-15 knots this afternoon and isolated 
showers arriving in the marine area tonight.  Models have initialized 
well, and no watches or warnings are valid at this time.

AVIATION:  VFR conditions are expected to continue.  For more information 
see www.weather.bm/aviation

SHORT TERM (Thursday & Friday)
Upper ridging over our area begins to be pinched by a strong trough 
slowly approaching front the northwest and another, weaker trough, 
approaching from the southwest.  A couple of showers are likely over 
the Island in the early morning as the first trough moves away.  
The rest of Thursday looks to be mainly dry with a few more clouds 
as tropical moisture begins to increase.  A second trough arrives 
Friday, brining a few more showers to our area and increasing clouds 
again.  Winds begin to decrease on Friday as high pressure continues 
to fight for dominance in our area.  Models are in good agreement 
on the winds, however, disagree on the location of the isolated light 
showers.  I have maintained a broad timing in the showers on Friday 
as there is no real agreement in the models.  The UK model does increase 
instability on Friday and there is a slight chance that a thunderstorm 
advisory will be needed.  No other watches or warnings are anticipated 
for these days at this time.

LONG TERM (Saturday & Sunday)
The upper trough to the northwest draws closer on Saturday as the 
trough to the southwest relaxes.  On Sunday, the forward side of 
the upper trough pushes into our area.  Lingering moisture remains 
in our area as winds become light and variable for Saturday.  The 
forecast remains broad for the weekend as models continue to struggle 
with the timing of the isolated to occasionally scattered showers 
in our area.  Later on Sunday, a low pressure system and associated 
cold front continue to slowly move away from the US East Coast and 
towards our area.  This increases the shower potential for Sunday 
night as the cold front approaches.  The ECMWF remains the wettest 
of the models with up to a quarter of an inch of precipitation through 
the weekend.  No watches or warnings are anticipated for these days 
at this time.

TROPICAL UPDATE
NWS National Hurricane Center Miami FL   200 AM EDT Wed Aug 5 2020

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:  
The National Hurricane Center is issuing advisories on Post-Tropical 
Cyclone Isaias, which is moving rapidly north-northeastward over 
eastern Quebec.

A small low pressure area located a few hundred miles southwest 
of Bermuda is producing minimal shower activity.  This low is forecast 
to drift southwestward during the next couple of days, and any development 
is expected to be slow to occur due to dry air and 
increasing upper-level winds.  * Formation chance through 48 hours...low...10 
percent.
* Formation chance through 5 days...low...10 percent.  Forecaster 
Berg