"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".

Wednesday, July 13, 2011

Enhanced Version Of Yesterday - Some Stronger Storms South (??) FloridaG

GOOD INSOLATION (heating from the sun) IS UNDERWAY AT 11:00AM. WEST COAST SEA BREEZE HAS BEGUN NW FLORIDA. EAST COAST SEA BREEZE ALMOST DUE SOUTH LIMITED TO THE CAPE AT THIS TIME. Showers have begun to form and between 11:30AM and 2pm should increase in number and strength, especially over South Florida where none exist. NOTE: This post assumes there will be activity over South Florida today. This will be a driving factor for Central Florida later today. Thus, if it does not manifest in South Florida a lot of what we have written below can be disregarded, almost in full.

SYNOPSIS (The "In General" Look): Today looks much like yesterday from all appearances on the broad scale. There is a difference though. Namely, a trough of low pressure in the mid-levels is starting to develop off the U.S. NE to Mid-Atlantic Coast and slants back into North Central Georgia. The long advertised surface front (stationary over Georgia) is getting to be aligned with the mid-level trough. Meanwhile..a weak circulation is forming in the mid-levels south of Panama City, and this can be seen as causing the enhanced area of shower and thunderstorms off their Gulf Coast.

The sounding at KSC looked almost identical to that of yesterday. The one in Miami is actually showing colder air aloft than those at JAX, KSC, Tampa, and Tally. The moisture levels at MIA, and as indicated by water vapor satellite derived imagery show that Dade County is about the driest location in the state, but not so dry that a storm or storms cannot form into this location. The Big Lake breeze is already becoming active into Palm Beach county with a weakly developing low level W-SW flow just above the surface. 

MID LEVEL WINDS AND MOISTURE. There is the low circulation near the Panhandle's Gulf Coast. It is just a bit drier over SW Florida and Dade County /Keys.  Note the broad expanse of westerly winds over the North 1/2 of the state closer to the developing mid-level low (and trough further north) where the pressure gradient (change in pressure with distance) is a small bit tighter (more drastic). South Florida/Everglades is 'almost' out of the picture with the enhancing mid level winds but still moderately unstable.

TODAY: Outside of these synoptic scale changes in the mid-levels regarding the winds, much of the state is starting to become uniformly unstable. The area MOST stable/least likely to see much activity earlier today is mostly the North 1/2 of Brevard County, especially east of US1. For other areas from Ocala/Gainesville/Ormond Beach/JAX/New Smyrna it's just a matter of time for the west coast sea breeze to push eastward. A few showers could form near the intracoastal, but the bigger activity will wait another 3-4 hours as the west coast sea breeze continues east bound.

SOUTH FLORIDA: Meanwhile, the Lake Okeechobee Breeze has started to a small degree. Cold air aloft and weak steering will dictate storm motions to be nearly stationary, but will propogate newer formation along the weak east coast sea breeze combined with the Lake Okee breeze close to I-95 if not east of there over Palm Beach, Martin, and Broward Counties as well as Okeechobee County, maybe a bit later in the Northern Part of that county.  Colder air aloft per MIAs sounding might mean some stronger down draft winds, especially in Broward and maybe even interior Dade where the upper levels are a bit drier. These storms would rely on outflow from storms further north to form..which isn't a full on given. 

NORTH FLORIDA: West Coast sea breeze is acting much like yesterday with similar soundings in the' temperatures aloft' world. Not expecting anything strong, but they could become more efficient at producing lightning the further east they progress due to greater instability 'heating up' the longer the sun is up. Some of these storms might be able to work off shore or get east to I-95 toward US-1 before they start to decay, especially north of  Daytona Beach.

1 (one) Meter winds courtesy of Melbourne's NWS Office provision on the internet.  Note the blue fields. Those are slightly stronger winds. We see westerlies strengthening over the Gulf and toward the West Coast. These are enhancing the west coast sea breeze there. We also see little 'bubble lows" setting up along the immediate coasts and by some larger lakes (blue arrows). There is also a few closer to the 700mb trough axis (drawn in red..this might actually just be a weakness in the ridge), OR weakening of the ridge up that way near I-10. These could be reason for a shower to form heading toward early afternoon. There is a down right trough along the SE Coast of Florida from Dade to Palm Beach County. Another reason to believe there could be storms close to the coast there. Other bubble lows along the SW Coast. These could form into weaker thunderstorms as well by early afternoon. I'm ignoring the one over North Brevard. That one is either stronger than shown toward N. Titsuville/Mims. 

CENTRAL FLORIDA: Central Florida currently has the most moisture in the mid-levels per some model guidance, although I couldn't really see it on soundings. This is a bit of a typical WSW flow day, albeit, weak. Usually, Central Florida is the last to see the rains on this day...especially toward the East Side. There is a sea breeze out by the cape..but it is nearly parallel to the shore rather than directly on shore at this hour. This would mean that the convective shut-down engine toward US1 might not be as much of a factor today if the direction holds true to form. Additionally, not one piece of guidance indicates that the winds out on the islands will be anything but SSW, up the waterways today. In fact, they show the winds to lose any semblance of 'sea breeziness" after 6 or 7pm. This will enhance low level helicity up the coast from near the Pineda to Daytona Beach, with the off-hand enhancement in N. Brevard West of the Space Center. Might see up and down rain showers near by this location today though before later this afternoon.

BIG STORM TIME: 4:30pm -7:30pm, Believe most of South Florida will be getting turned over/worked over by latter portions of mid-afternoon with an outlier storm resulting from any remaining boundaries. North Florida will remain active until about the same time..but changes are in store which more directly will effect that area, so it's harder to pin-point times/locations. 

Equally as difficult is East Central Florida. It does appear that like that past two days (more so yesterday) outflows from Okeechobee, Martin, and maybe St. Lucie County would work northward toward Orlando to Titusville to Melbourne. Additional outflows from that activity going across the peninsula further north could also come into play from the larger activity.  By this time though the west coast sea breeze might be East of Orlando or very close to it. Boundary mergers, no matter how unfavorable for storms the environment might be over Seminole, Eastern Orange, Brevard, and Indian River Counties should be able to overcome those weaknesses and result in a good downpour of rain/rains in this area, somwhere.

Two scenarios could unfold 1) That of the past two days...with a large area of rain and lightning forming in toward North Brevard/Southern Volusia north of SR 528 and working off the coast with time, barely phasing the rest of the county. OR 2) Activity, if it gets going as it COULD (emphasized) further south, would enhance activity building northward into SW Brevard closer to the coast, propogating further activity up US1-I95 toward Cocoa Beach/Cape Canaveral after 7-8pm.  This has happened in the past, but remains an outlier due to the fact that it is so rare to occur and is not really depicted by the mainstream models.

THURSDAY? (we ask): Good question. A lot will depend on whether a low forms off the Panhandle, and what the net affect of that would be. Based on past guidance, it appears we could have one more day of activity mainly for Central and North Florida with the ridge axis over South Florida starting to lift back to the north with less activity down that way and favoring more toward the west side as the day progresses. Further north, North Florida appears will get MORE wet with time, whereas most of all Central Florida form Coast to coast plays the waiting game, with a lot of its weather dependent what happens between those regimes to the North and South, combined with what happens in the mid levels once again. Oi Vey

FRIDAY-SUNDAY: More of an "interior, later in the day pattern establishes, primarily over the North half of the state. Friday could be fairly active though from Southwest Florida up toward I/4 (Orlando) then along and North of I-4 toward Daytona Beach. It is thought this will be a sea breeze merger day favoring the west side south of 528 toward TPA and closer to the east along I-4 toward Jacksonville.
Read captions, keeping in mind the comments made in the paragraphs above

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