"But seeing they could not See; hearing they could not Hear"
“The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

"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".

Wednesday, August 3, 2011

Emily Musings: Isolated Showers and Some Thunder Very Late Other Than Far South Florida

A few showers here and there near lakes and on sea breezes in the green area in general. Some Afternoon to early evening thunder is possible earliest Far South Florida, and just maybe further north along the East Coast toward South Brevard after  6:00pm, but  that 'might' be stretching it, considering the latest trend of drying in the mid-levels last hour everywhere other than south of Lake Okeechobee. Moisture convergence toward dark can work some magic though..(as was the case last night toward Gainesville) there might be a storm or two into South Central Florida when all is said and done..if south..likely over Osceola county or Okeechobee County.

TODAY/FRIDAY: Won't go to much into the details for today through Friday. Warm air aloft is expected to continue; thus, mainly only very late afternoon to mid-evening thunderstorms, generally over South Florida.  Thursday looks to be the overall driest day state wide, but not completely.  Storms should remain quite isolated most of the day (South Florida), but might become more scattered, possibly a bit stronger after 5:30pm over South Florida.

Back to today:  The west coast sea breeze should reach toward the East Coast toward early evening. This might generate a thunderstorm further north along the east coast as drawn in, but given the latest trends..that might be wishful thinking for those who like to hear thunder for dinner music. There is a reason why South Florida might not flare up too much later today. See the image below. There is some thin, high cirrus clouds moving in the direction of the South half of the state at this hour. If they overrun South Florida after might squash the rain chances. That is something that will have to be monitored by the NWS down that way. ...for within the next few hours is when the sea and lake breezes..and any other showers that form will generate boundary intersections to create the best storms for that area of the day...which might be impeded by those high clouds if they move in.

EMILY: Latest information concerning Emily as of 1pm today indicates the storm has not changed in strength. The official forecast track from overnight has shifted back toward the West (after having shifted east earlier) bringing the storm closer to the East Florida coast than any previous forecast. Interesting, in that the latest GFS/NAM solutions have it even further to the EAST (and away from Florida)...interesting hypothesis.

IMAGES: Note these two images. The first image shows that all the thunderstorm activity if off to the SE side of the surface circulation. There is almost one  storm that recently popped up on the NE side. To the north of the storm, indicated by the 'white, circled "L", is the Dominican Republic.

The first thing I wanted to point out other than how very small the circulation is with no rain wrapping around the surface low (or even above it) that the storm has been moving WEST since early morning. This is important because the latest Official Forecast Track by now has the storm moving almost in a Northwest direction.  Just how long this westerly motion will continue is not known...but surely the next official forecast track that is released will also be revised.  Note that the further west it goes, if we assume it will eventually curve north, the better the chances are that it will cross less land mass of Haiti. Perhaps it will take the channel between Haiti and Western Cuba.

The next item of interest is the water vapor image showing the amount of moisture in the mid-upper levels of the atmosphere:

See Emily at the bottom of this image. Then see the dry air to its north? Can an already weak to moderate strength tropical storm make it across the high elevation of the Dominican make it through the dry air? Not very likely unless AT LEAST the dry air moves out. Perhaps the storm is avoiding the dry air..or maybe even being steered by it by staying more toward the south.

So what we have here is quite the conundrum. Dry air to the north, what looks like continued shearing winds to the north of the storm until at least tonight...some shearing winds to the SW of the storm as well, and mountainous terrain to its north.  The best chance for Emily at this point if it is to head north is to take the passage between the DR and Cuba.  What if the storm gets TOO far west and curves into Eastern Cuba  (?)..that is the most mountainous region of the island.  If it continues to go too far that time the next upper level trough that has been forecast for many days..before Emily even existed...will start to be digging into the Southeast U.S....with more shearing winds. This essentially means the storm will be headed for Honduras.  In other words, at this point there's no reason to sweat this storm. This also means Haiti, now trimmed of trees...could succumb to flooding rain fall...and landslides. Good grief, enough already for Haiti.

There is one opt out though. Perhaps Emily will simply open up into a significant 'open wave' and take the turn ..northward..bringing plentiful moisture northward in the progress. This would bring a better chance of rain to Florida heading into Sunday

No discussion of a tropical storm is complete without showing the forecast track plots engineered by some of the models. The official NHC track it the heavy, dark red plot in the center...but check out that margin of error. The best chance for this storm is if it heads as far west as possible at this point. Even still, note that every single track is showing a NW motion from the point of origin, yet Emily is moving west as of the last official observation. There goes those plots right off the bat.

IN ANY CASE: No matter what Emily does or does not do, the outlook in General For Florida is for increased rain chances around the Monday time frame. Even if Emily does move north..the moisture return will come once the storm gets north of Central Florida. If it passes just to the east of the state, someone is going to get 'dry slotted'...which mean no rain for a time as it passes by.

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