Gulf of Mexico, in December

[Franke]

I am planning a trip up the Yucatan and Key West for the month of December.
Seems like I need to pay great attention to the cold front marching down from the States.

It seems like some people paint a bleak picture for December.
Others maintain that most fronts that time of year peter out well to the
North of my route. The frequency of cfs also concern me.

Somebody tell me please where I can get complete, and competent info???


Thanks,

franke

[belizesailor]

Yes, fronts would be my primary weather concern. But if you play them right they can also work to your advantage by shifting prevailing winds. The ugly weather will be at the leading edge of the front. You can hole up somewhere for that to pass and then catch the shift on the trailing edge with more stable weather, but maybe some leftover sloppy seas.

Maybe "most" fronts don't push that far south in December, but plenty do, and its typically the stronger ones.

I worked for years in the charter industry in Belize and we would get cold fronts pushing down from the USA from December to as late as March. In 2011 we had fronts thru the entire month of March. The ideal time to transit the GOM is April-May. Its after cold front season and before hurricane season.

To access the risk you need to get familiar with Pilot Charts, NOAA Synoptic charts, and maybe a pro weather router like Chris Parker.

[travellerw]

I haven't made the transit yet, but I understand that those cold fronts play havoc with the Florida current. Even if they peter out well north, I've been told the current will stack up and its akin to being in a washing machine. You will need to plan the jump between Key West and Mexico (Isla Mujeres) carefully.

[belizesailor]

Originally Posted by travellerw

I haven't made the transit yet, but I understand that those cold fronts play havoc with the Florida current. Even if they peter out well north, I've been told the current will stack up and its akin to being in a washing machine. You will need to plan the jump between Key West and Mexico (Isla Mujeres) carefully.

Yes, winds counter to current will cause wave period to shorten and height to increase. Conditions can get quite nasty in the Yucatan current (between Cuba & Mexico) and the Gulf Stream. Also, usually to a lesser degree, the Gulf Loop current.

For this route you want to get familair with all three of these currents.

[Franke]

Thank, guys for that input. What is the frequency of cold fronts in the gulf in December?
Would it not be possible, to time the passage to avoid cold fronts altogether?

[skipmac]

Originally Posted by Franke

Thank, guys for that input. What is the frequency of cold fronts in the gulf in December?
Would it not be possible, to time the passage to avoid cold fronts altogether?

Frequency varies every year. It's weather and not that predictable.

Some years I've seen very few strong fronts that made it to the Straights of Florida until Jan/Feb. Other years I have seen them start in early Oct and a new one hit south Florida every week more or less and continue until spring.

All you can do is watch the weather when you're ready to leave and pick a window. The fronts are usually pretty predictable. When a strong front hits Atlanta it usually arrives in south Florida within 1-2 days or the Straights in 2-3 days. Hang in NE Mexico until you get a couple of clear days. If you have no other options for weather you can get a synopsis on WWV.

[belizesailor]

Sometimes they seem to develop a rhythm of every one to two weeks, but as posted, timing varies by year...and with weather patterns changing its impossible to predict what next year will bring.

If you watch the Synoptic charts you do get several days of warning. Upper level wind charts are also useful in judging where a cold front might go.

In winter months I would plan for short hops between fronts. Short weather windows are much more likely to forecast correctly. The further out the forecast the lower its probablility of being correct.

See below for NOAA charts. The surface analysis and forecast charts show graphically the position and predicted movement of fronts. These same products are broadcast via SSB for weather FAX reception so you can get them underway.

weather.noaa.gov/fax/gulflatest.shtml

[model 10]

Originally Posted by Franke

Would it not be possible, to time the passage to avoid cold fronts altogether?

Sometime in May or maybe the very end of hurricane season but maybe not then depending on the year. Sometimes they seem to start a week after hurricane season ends.
Unless you are good at forecasting, I would sit in Isla and listen to Parker everyday. If you don't have the time to do that you may need to wait untill late spring to go. There are weeks throughout the year when it would be OK to go but you would never know, unless you just wait in Isla Mujeres for a good forecast.
Note: a 1-2 meter swell from any direction in the Yucatan is too much in my opinion. Next trip for us will be more like 1/2 meter and some wind from the SSE or ESE.

[fogmachine]

As beliezesailor said, NOAA posts weather fax for the gulf region to weather.noaa.gov/fax/gulflatest.shtml. If you're holed up in a marina with internet access you can retrieve all of them directly into OpenCPN using the WeatherFax plugin - they're under NOAA -> New Orleans.