Saturday, February 22, 2020

Watching the Weather

Front After Front
We are aboard the boat in Stuart, Florida. The plan is to depart and head south to the Palm Beach area by Monday night and Fort Lauderdale Tuesday night, trying to get into position to cross the Gulf Stream Wednesday to Bimini. It is a trip that may or may not happen, depending on the weather. I have no statistics to back this up, but this year to me has had an unusual weather pattern of one cold front after another passing through every two or three days, rather than about once every week or two as usual.

Normally when a cold front passes, the winds clock around from south to west to north, and the north winds are cold and strong for two or three days thereafter. That is exactly what happened here when the front passed last night with heavy rain and we awoke this morning to strong cold winds from a northerly direction. Strong north winds blowing against the Gulf Stream current make waves stand up and get very steep, and uncomfortable. So the usual practice is to wait a few days after the front and dash across the Gulf Stream before the next front arrives. The problem for quite awhile this winter is that the next front arrives before the winds ever settle down from the previous one.

The best advice I ever got about crossing the Gulf Stream was from a book entitled A Gentleman's Guide to Passages South by Bruce Van Sant. He said simply: "Under prevailing conditions, wait until the Offshore Forecast says south of east winds of less than 15 knots and seas less than three feet." He was speaking more of comfort than safety. Our boat can handle much rougher seas than I can. But in fact, under the current forecast for Wednesday, we should have southeast to south winds 10 to 15 knots and seas of two to four feet, pretty close to what he advised as the maximum.

There are two problems though. This is Saturday and a lot can change by Wednesday. And second, there are today many more models and forecasts than the National Weather Service Offshore Forecast, and they are not all in agreement. For Wednesday, Chris Parker's Marine Weather Center says: "Brisk SSE-S wind prevents comfortable travel Tue25, then very brisk S-SSW wind keeps travel window closed Wed26." PredictWind, an app I study regularly, calls for 2.5-foot waves Wednesday at noon between Fort Lauderdale and Bimini, but predicts winds of 19 knots. Using PredictWind's second model, it predicts similar seas but winds of only 13 knots. Its Euro model has winds at 19 knots and seas of 4.2 feet.

Too much information I think, but I have been watching it obsessively for the last few days. It does show that we are on the margins. The answer will not come until Tuesday night or early Wednesday morning when we can see what the sea buoys tell us about wind and seas, and see if the forecasts for the day have come more into agreement. If we can't go this time, we wait for the next front to pass and try again.

I'll keep you posted. The good news is that I am happy to be on the boat, no matter where it is. We will eventually get there.

2 comments:

Louise said...

That last front was strong enough that we had gale forecasts in Fort Lauderdale a couple days ago. It made us scurry to get the boat docked in an unfamiliar marina before having to do so in 25kts. Fortunately, it never got that bad. I agree that this year the systems are arriving fast and furious!

Unknown said...

Looks like another front coming through on Thursday. I just saw you going south through Boyton Beach. Good Luck!