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The calm subtropical high

Extreme calm as high pressure dominates.

00Z March 2 forecast

Current weather:
We have data from you again!!! HOORAY! It looks like your wind is really low, below 5 kts, and over the last day its gone from easterly to northerly and back to easterly. Recent ASCAT passes are showing these light winds too. It looks like there are stronger winds (10 kts) just a fraction of a degree to your south. Pressure is hanging around 1020 mb …. From the surface analysis, you are not far south of the subtropical high, which is supposedly only at 1020 mb. It’s at about 23 N 43 W. You’re at the SW edge of what RTOFS claims is an occasional but somewhat disorganized eddy remnant, so maybe you are or maybe you aren’t feeling that. WWIII has signifcant wave height at 2-3 m from NNW with 13 sec period, all swell.

Short term (next day or two): The high is sticking around. Winds will be light and changing directions as it wobbles near you. They might get up to 10 kts NE briefly Sunday but might die again. Monday…. You might or might not experience favorable currents, but RTOFS at least definitely doesn’t have contrary ones.

Longer term: This high will stay in place for a while. A front extending from the tropics to the midlatitudes is developing to your west, and th ECMWF brings it through your area next Wednesday, but the GFS has the high deflecting it north. We’ll keep an eye on it. Swell should decrease in height and period and turn to NW, until it picks up again Monday.

Clouds: I’d say it looks 20% cloudy where you are. Do you see a bunch of clouds to your south? They don’t look incredibly deep, the IR satellite just picks them up a little, but maybe you can see them.

Sat (March 2): <25% cloudy
Sun (3/3): <25% cloudy
Mon (3/4): 75% cloudy
Tuesday (3/5): 50% cloudy
Wednesday (3/6: maybe overcast (100% cloudy)

Next 12 hours (00-12 Z)
Pressure: holding steady while the high bobbles around
Wind: E, SE, NE, < 10kt
Waves: 2-3 m, 13 s, from NNW

Intermediate 12-18 Z
Wind: Turning S, or E, < 5kt
Waves: 2 m, 13 s, NNW

Tomorrow evening 18-24 Z
Wind: Basically dead calm
Waves: 1.5-2 m, 12 s, NNW

Forecaster Pendergrass

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