Questions Abound Today Concerning Where, When, and If

Storm Approaching Merritt Island toward Port St John on Saturday viewed near the South Gate Entrance of the Kennedy Space Center near Port Canaveral. It is evident from this image that this storm was 'feeding' on the mid-level boundary across Central Florida by the long line of clouds on the right portion of the image . Although not frequent, this storm ejected powerful lightning bolts and dropped very heavy rain. Another storm was further north, and outflow from that storm fed into this storm, further magnifying its very small but dutiful strength.

Zoomed in a bit. Lightning was coming out well to the left and right of the rain core noticeable in the center

TODAY: Very difficult forecast for today. And no surprise. Recall the model forecasts for today were 'dumped', and it was stated we'd figure it out today?...It is still hard to figure out even at this hour.  After looking through overnight guidance, that which came out so far this morning, as well as monitoring actual information using 3 hour animations of the changes since sunrise...today's post is again in lieu of any model. They all agree to disagree concerning where and when it will rain today...if anywhere.  Thus, here's the line of thought and how it transpired.


Initially, it looked like good rain coverage over most of the state along and south of I-4 with the most south of Lake Okeechobee oozing into toward East Central and perhaps toward Jacksonville. But....

IN looking at water vapor loops, it appeared that a weak circulation off of SE Florida which contains drier air might prevent the tropical wave forecast to move in from the East to have the effect thought in regard to increased rain chances over South Florida (which was to be high end coverage). In fact, it is now noon and there is not hint of rain to occur anytime soon. In fact, after reviewing time sequenced loops of the past several hours, this area is becoming more stable. There is moisture, but it is at the wrong levels to generate storms.  The other area is the old boundary across North Central Florida. It seems to have moved little, and actually a storm went up along it off shore earlier this morning that showed rotation and quite a bit of lightning. This boundary remains in place today, but not nearly as clearly.

Rotating Thunderstorm Off Shore Along the Boundary Across Central Florida

See the colored text for important  finer details. With all factors considered and after some internal 'negotiating a reason for rain', the case for best rain chances was  created. Storms were thought to form west of the coast of SE Florida and move toward the West Coast as well as over the Keys. Across Central in the white lines is south of that boundary that has been in place for 4-5 days. Out in the Northern Gulf though appears to be a disturbance moving east to move over the state..or approach after 5pm. This could add lift but add nothing for an atmosphere too dry over NW Florida but toward JAX is a different story.  The SPC analysis page also shows a circulation over NE Florida and it now shows up on the satellite image last hour (below). I was also watching for an outflow boundary to move west from the Atlantic to maybe start off some showers around 1pm ..but that seems to be fizzling well off to the east...although one model managed to pick up on it, to generate rain by 1pm. Not going to happen though

The circulation near JAX is evident, and another along the East Central Coast which was on analysis is not evident but drawn in with a question mark. Note how at noon nothing is happening  anywhere. 

Finally, the last factor that just became evident is that unlike any model forecast has shown and which explains why nothing is happening, most of the state has become capped in the mid-levels with convective inhibition. Thus, it looks to be another late day to evening rain chance, if any. One model showed close to no rain most anywhere today which might have ended up being right on...


The other 'finally' is that the next trough approaching from the WNW-NW forecast to up the rain chances on Monday might be moving in faster than thought. This could mean less rainfall coverage tomorrow due to the bad timing of its arrival for late day storms (except toward the South Half of the State). Thus, the forecast for Monday is in limbo. 


And one more thing while on a roll, so too may be the forecast for Tuesday out to lunch (per TV). Much depends on how strong, big, and in which direction Maria takes in the next 48 hours.


 If it stays further to the east than thought, the state might not get into the sinking air surrounding the storm..so there could be some rain chances as shown by the very conservative and unreliable NAM model.  The next boundary moving in tomorrow could get hung up across South Central Florida on Monday (in that case) and be a rain player for 'somewhere' for Tuesday, of isolated fashion.  Beyond Tuesday, the rain chances dwindle either way with an up tick on the weekend coming up.

FINAL CONCLUSION: This might be way over generous on the rain fall today but watching these areas when push comes to shove. The red is most concentrated rainstorms, and the areas near those red L's need
to be monitored. South Central is where the most unstable air is evolving as of noon time with the greatest moisture in the mid levels right along that old boundary shown in purple. With stronger upper level winds pushing in from the WNW late today and increasing mid level winds late as well, storms appear to be late in coming (after 5pm) once again north of Okeechobee County/St Lucie County. If a storm forms along that boundary and rolls off to the southeast (or even northeast toward Volusia), it could become quite potent toward Seminole County and into NE Orange and North to North Central Brevard County or into Volusia as it meets the east coast sea breeze from the SE - SSE which will form later in the day to any degree of 'strength'.  If it can rain...unlike some models show nearly none, we'll find out later today. But , if so, it could linger over interior South Central toward the east coast of Brevard/Indian River/St. Lucie County until mid-evening.