Interpreting pressure forecast
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A little help with barometric pressure meaning:
The pressure display for noon on oct 28, comparing the North Pacific and the Caribbean shows the hurricane by Jamaica pressure bouncing between 28-29” hg with no high pressure near. The low in the Gulf of Alaska shows a lower pressure and very tight isolines, and 30.3” high pressure to the south.If flow is caused by a pressure differential, where is the pressure differential driving the hurricane winds near Jamaica?
Or do I have a conceptual understanding problem? -
@bbbsss
In a few words, tropical cyclones are born in the low pressure belt that is present along and on both sides of the equator (warm air tends to rise). Thus, we observe that the high pressures of the subtropical belt (lat 30°) “feed” the intertropical low pressure by the trade winds and therefore tropical cyclones. But the engine of hurricanes is not a difference in pressure, but rather the temperature at sea level.
Near the subpolar latitudes (lat 60°), we observe an alternation of high and low pressures. It is a different system.
See this useful article about tropical cyclones
Note that the atmospheric pressure in the hurricane center cannot be correctly forecast by weather models. It is measured by flight recon. -
Have the government cuts affected the accuracy of Windys predictions?
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@bbbsss
I guess you are meaning the US government?
I don’t think so. The default weather model in Windy is European.
NHC say they not affected, so the Hurricane tracker is OK.
Concerning GFS, HRRR and NAM models, I don’t know.
