"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".

Sunday, August 14, 2011

Strong/Marginally Severe Storms North and Portions of North Central Florida Today

There is a chance of very strong thunderstorms today with the only real hazard being excessive lightning, although wind gusts to 55-60mph could happen in storms North of Route 46 (Brevard to Seminole County). Tiny hail could occur in some storms..although nickel size is a small possibility in storms north of Daytona. More in today's write up. 
TODAY: This image above is the 500mb analysis at 8AM. Does not show much except where the southern extent of the upper level flow extends today by the solid black line. We see the radar overlay here too. Something is sparking  some thunderstorms SW of Pensacola, and that trigger device might work into North Central Florida later today. A stronger pocket of energy is expected further north into NE Florida later as well.  

Storms should start out by early afternoon over North Florida spreading east, and eventually over South Florida..but yesterday there. Tampa Bay area will also get in on the act by 1pm.

HOT EAST SIDE TODAY NORTH OF VERO BEACH: Unusually hot once again as the theme has been with a delayed Sea breeze north of Vero Beach or Ft. Pierce with highs at the beaches in the mid-90Fs...if not warmer..with high dew points..Heat Indices (otherwise labelled as the 'feels like' temperature) will approach 105-112F..A1A north of Melbourne Beach). The most thermal  instability forecast by all models this morning is expected to exist across Central Florida today, with the most wind energy over North Central and North. Even at this early hour the Convective Available Potential Energy (CAPE) is up to 3500 J/KG which is approaching very unstable..these values reside just off shore both coasts but will fill across by noon. The mid levels are moderately unstable already in the same is the RUC (the Rapid Update Cycle model) forecast for 2pm of the instability. The red (and the darker red) more and more unstable..decreasing to pale blue is barely unstable.

Forecast CAPE (available energy, the higher it is, the more unstable the atmosphere can become) for 2pm today. It is possible these values will be even higher than presented in the model. This has been the trend...but these look very reasonable. It is clear the most instability is over Central Florida and far South Florida by that hour (and near JAX).  More instability will work in across the Panhandle as well.
Rains, showers, and some thunder will work west to east across North Florida toward JAX and spread south with time toward Ormond Beach. Meanwhile, the east coast sea breeze is expected to develop first over South Florida and progress up the coast to near Port Canaveral by 2-3pm...but remain very close to the coast north of Vero Beach...especially in Brevard where it might not progress any further than US1 to I-95.

As storms (assuming they develop) approach from Inland Volusia/Osceola/Orange/Seminole Counties) and interact with the sea breeze south of Mims as they approach I-95. 

There could also be an up-river (from the south that is actually stronger than the sea breeze occurred yesterday)  component over Brevard County and into the Bight area of the Cape. 

If so, storms could be conditionally severe (based on that factor) near Titusville, Mims, Oak Hill, and Port Canaveral south to the 520 Cswy...additive factors similar migth play in around Ft Pierce, but not likely.   There is also the chance that, depending on the timing of storm activity further north..that outflows from those storms could press south to add yet one more variable into the quadratic equation of CAPE/Lifted Indices, sea breezes, and upper level divergence). That added penta-factor could result in a river or oceanspout...(waterspout) near the Merritt Island Wildlife Refuge/Port Canaveral/South Cocoa Beach...or just offshore further south toward Vero..but the further north..the more likely this possibility. For that to occur, though, the storm (if there is one) would have to form east of Orlando and move in after 5:30pm when the up-river wind is at its strongest.

The latest RUC forecast indicates there will be some divergence or weakening and simultaneous splitting of jet stream level winds later today. When this occurs way over head..storm tops can rise up through those splitting wind fields to greater height. This image might be a bit overdone..and believe this will more likely be the case either Monday or Tuesday...the waterspout potential..possibly more than teeny weeny..will be on Tuesday.:

BEYOND: Storm chances continue Monday - Thursday....with a variation to the theme each and every day. It is possible a sea breeze will not be realized on Monday almost anywhere..that will need to be reassessed in the morning on that day.  Otherwise, the GFS has flip flopped between different variations as Wednesday approaches...making wind fields for an early sea breeze from Wednesday and beyond, but maintaining a WSW to ENE flow aloft in the mid-upper levels. That could mean very late day storms again along the east coast..if they can make it that far. Most likely west of I-95 and decaying as they approach the coast.

The other factor to consider working into Tuesday is the amount of moisture available. The GFS was trying to bring a frontal boundary into South Central or even Far South Florida by Thursday..really taking the rain chances down due to dry air behind that boundary (no temperature effect). That seemed quite odd for of 2AM it has now backed off..with only a day or two of drier air North of SR 50...Tuesday and perhaps Wednesday.  

Strong storms should again be possible toward the East Side of the state from Vero to Titusville on Tuesday...especially since a sea breeze is again expected to develop most everywhere...and upper level divergence as shown in the image above will be primed if all things pan out as depicted.

TROPICS: There are no tropical threats for quite some time to come...that is, until the next GFS comes out...kidding...the Saharan Air Layer (of dry air) is cascading off the West Coast of Africa like a dusty, dry waterfall. There were 2 areas of interest out there yesterday..but as of last night they looked all but gone. The Hurricane Center is still ogling  them though..but even still..the one that might form into a depression  looks destined to be casting nets and hooking bait east of Bermuda if it lasts that long.  The area of dry air circulating out there North of Puerto Rico and the Dominican is shrinking in size though as it only rotates in place, shifting a bit north and a bit south.

Surely anyone sailing out in that area toward the NW Coast of Africa, if this were the old days, would be suffering from the delusion known as 'calenture'. Back then, after months at sea they would begin to hallucinate upon day after day of clear but dusty/hazy/humid air...they'd see the green ocean waters as fields of, moist, lustrous, greeting pasture..and in their hysteria..would try to walk upon it. Man over board! I guess they'd end up in the sarcophagus if their bodies were ever retrieved in the days of King 'TUTT'...per archaeological digs.

The Tropical Upper Level Trough (TUTT) is closed off and filling closest to Florida as shown...but check out all the Sad and Loony Air (Saharan Air Layer personified) coming off African like the Niagara Dust Falls...wouldn't want to take a tour in a raincoat out there.

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