"But seeing they could not See; hearing they could not Hear"
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"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Friday, September 11, 2009

Big Changes Begining Late Today

(small funnel cloud and accompanying rain showers from Thursday - 9/10/09)

Big changes are now occurring as was alluded to would happen today in Wednesday's post. The morning KSC sounding and forecast models are all gradually coming into agreement of this atmospheric transformation so some forecasting challenges are at hand.
Now and First 3/4 of Today: Latest sounding indeed shows that over the past 24 hours the easterly steering flow has become shallower and shallower. There is a shift of winds now just above 10,000 feet to a westerly component whereas the past couple of days that shift was up at 20,000 feet. It will continueto slowly lower during the day, but any impacts will not be realized until late today into tonight when it sets up in earnest. Meanwhile, the overall moisture content/depth has likewise increased as well as instability.
A weak surface boundary extends from a strong low pressure system off the New Jersey coast south and westward across South Florida and into the Gulf of Mexico joining the low pressure system that had been trying to form off North Central Cuba (which is now moving WNW). As this low moves further north the boundary will do so in tandem...impinging into the southern areas by very late today. I think the models are a little fast on the course of events, so we may see little impact of this today north of a Vero-Tampa line. If anything, it could be initially drier from points north of a Ft. Pierce to Sarasota line...but the change is coming.
Ocean showers are not really making it onshore today (unlike yesterday) due to the fact that the easterly steering flow is being begrudingly disrupted, and we are thus falling into a temporary nil-flow pattern until tonight. However, with ample moisture, instability, sea-breeze/lake breeze mergers, and the aforementioned boundary all in play today there will be storms today just north, along, and south of the boundary. Showers/storms will be limited to highly isolated until after 7pm further north and into the overnight.
Tomorrow (Saturday) looks to be an active day weather-wise, so I hope you got those "honey-dos" done. Break out the camera gear, the galoshes (do folks wear them in Florida?), and boot up the radar on the computer...never hurts to look at the sky too, because they'll all be needed by later today, tomorrow, Sunday...and from there the jury is closed.

Future evolution of this impending scenario will be described possibly as soon as later today if the changes become more evident or actually start to occur more rapidly than currently anticipated.

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