Thursday, May 19, 2016

Headed Back to the States & Summer Weather

May 19, 2016


Barefoot at anchor at Black Point
Photo Credit Greg Sadowski

On this stay we have spent about a week and a half here in Black Point, one of our 'homes' in the Bahamas.  We had planned to stay a little longer, but weather is encouraging us to get moving.

Everyone worries about the winter cold fronts, and they do have to be taken seriously.  They can come through with strong clocking winds, squalls and thunderstorms.  But winter cold fronts are fairly predictable.

When summer approaches, the weather gets more unpredictable.  The cold fronts lose power and do not push through, but rather stall and dissipate.  This often creates, what are called in meteorology, troughs.  These are unorganized areas of low pressure that can bring unsettled weather to an area for days and even sometimes weeks.

Also at this time of year, 'tropical waves' start coming from the south and east.  These are also unorganized areas of low pressure that originate in the tropics.  If they start to show vorticity (spin) they are a tropical low, if they gain strength, they are a a Tropical Storm; then they can become Hurricanes.  At this time of year it is unlikely the waves will get organized (but not impossible - a Tropical Storm passed over us in Miami in May a few years ago) , but even if they don't, they bring moist unsettled weather like a trough.

It seems that over 5 years of cruising, we have faced our most difficult weather conditions in early Summer when these conditions prevail.

So with that background, here is our passage plan back to Miami with weather considerations:

  • Leg 1 (Friday 5/20)  will be from Black Point up to Highbourne Cay in the northern Exumas.  Two days ago a cold front came through the Northern Bahamas and South Florida bringing strong thunderstorms to that whole area.  It stalled north of us killing most of the wind here.  This leg will be motoring, maybe with some motor-sailing.
Surface Analysis for departure Friday 5/20
Note stalling front across north Florida


Wind at departure Friday 5/20
  • Leg 2 (Saturday 5/21) will be from Highbourne Cay to West Bay on the island of New Providence (where Nassau is).  The purpose of these first two legs is to stage us for the arrival of another cold front Sunday.  We will probably stay In West Bay 3 nights allowing the front to pass.
Second cold front arriving Sunday 5/22 - Monday 5/23
  • Why not just stay in Black Point for this second front, the protection from the forecast light west winds is about the same.  Well, a tropical wave is forecast to arrive in the southern Exumas late next week and proceed northward, bringing squally, rainy weather. Our move north will hopefully keep us ahead of the tropical wave and give us a couple of days with moderate east wind before the squally weather associated with the tropical wave moves north. 
  • Leg 3 (Tuesday 24 - Wednesday) will feature a midday departure from West Bay, up the 'Tongue of the Ocean' to the 'Northwest Channel', then crossing the Bahama Bank over night, exiting the Bank at Gun Cay, and proceeding across the Gulf Stream to Miami. Hopefully we will complete this leg straying ahead of the tropical wave.
Whew!  I am sure more than you ever wanted to know, but this is cruising!

Tom
Anchored Black Point
Exuma Cays

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