Thunder and Showers South of Ormond, 'Katina' Incubating?

THE TROUGH OF IRENE IS BREAKING AWAY, PROGRESSIVELY LEAVING FLORIDA
IN A "STATE' OF LIMBO BY LATER TODAY/MiD-EVENING

FLORIDA TODAY: A bit of another conundrum forecast today, no things are set in stone by a long shot. The mid-level trough associated with Irene's Absorption is beginning to 'cut-off- as high pressure attempts to build in from the west toward the Mid-Atlantic. It still has a full 24 hours before its influence will be exerted further north where some strong storms are possible along the coastal mid-Atlantic. Near Florida, the cut off process is reflected by a weak surface circulation as shown above in the 'actuals', also reflected in short term model RUC.  Dry air is trying to encroach into northern portions of North Central. South Central and South are fully entrenched in moisture. Early start to convection has spread debris clouds to the east coast, so the forecast for the south east side of the state today is up in arms. Can thunder form with the cloudiness? i'm thinking no, but giving them the benefit of the doubt for now that outflow from activity further west could erupt some showers and maybe thunder close to the coast of Palm Beach County and South. Should mention, the Panhandle region and most areas along I-10 are going to start running into a big fire danger/drought situation if things do not improve there. It looks like they are almost already starting to see the end of the thunderstorm season, if not for good. High pressure will be building in later in the week, and it is dry.

NOTE THE CIRRUS CLOUDS SOUTH. The least amount of early cirrus, and where moisture is most ample, or ample enough, has the best chance of thunder today, some could be more active (stronger) along the region where the mid-level moisture changes from completely suitable to marginally questionable to support storms. The other problem further north is that with less cloud coverage inland, there is a better chance of a late sea breeze/river breeze (which never occurred yesterday). There is less near paper think cirrus in the sky today far East Central, so the heating in this area could produce a river breeze after 4pm. Sea breeze/river breezes will remain east of US1. Thus this begs the next question. Could stronger storms form along and East of US1 north of Vero Beach? I do not think they will be strong enough to exert that sort of influence today...so for now..no.

IN SUMMARY: Warm today with highs a few tics above normal before any rain approaches..north of South Florida and away from increasing showers and thunder going into early afternoon. Rains should start to move in by noon time from the SSW-SW Central/North Central. Some areas might see rain more than once due to earlier onset, especially inland and toward the west side.  If heavier storms develop more toward the interior, coastal areas will see mostly lighter rains and isolated thunder. All areas becoming cloudy by mid - late afternoon south of a Daytona.  


The sketchy area to also watch, although not highlighted in the graphic is the Flagler/North Volusia coastal areas. This area will be most influenced by dry, mid-level air in a region of strongest down draft CAPE (because of the drier air). Often, the drier air inhibits storm formation altogether because it is often associated with warm air as well in the mid-levels. That might not be the case today as the afternoon progresses. Hopefully  it has been made clear that nothing is a given today north of Lake Okeechobee.South Florida? I see what models are depicting, but not so sure the rains showing up in high numbers won't amount to clouds in high numbers instead, especially if more activity redevelops toward SW Florida.


TROPICS: No way Jose', you're history. Literally. Meanwhile, the bigger area of interest is SW of the Cape Verdes off the SW Coast of Africa where a depression was determined to exist as of 5AM. This area is large, and encased between two areas of drier SAL air (Saharan Air Layer) as seen below. The forecast track is show. This system will become most likely Katina within 24-36 hours or so. 

FORECAST TRACKS with the NHC track in white dead center. The main players are along and NORTH of the forecast track, whereas the 'others' are south of the track. THIS IS IMPORTANT. We see dry air on  either side of the track, so in order for the storm to sustain itself there is only one way to go for the next 36-72 hours. If it goes the more SOUTHERN route, the chances of Katina becoming a Major hurricane are much better. Sea Surface Temperatures are warmest in that direction as indicated by latest imagery this morning. Perhaps that is because of upwelling from Irene, although the storm was not strong over this area while it crossed here as only a wave or depression. It could become a major hurricane, though, either way.

For kicks, included are two storm tracks from 1964. Back to back big ones Cleo and Dora.
Note that they originated near the same area. Recall, the original forecast track of Irene for a good while was for the storm to hit Florida, but it never got far enough south and west into the Caribbean to perform like Cleo.

CLEO. IRENE  FORMED INTO A HURRICANE NEAR PUERTO RICO AND TOWARD THE NE TIP OF THE DOMINICAN REPUBLIC

DORA. NOTE: If Dora takes the more southern track, across the warmer waters, it could  track under the next trough of low pressure that models are depicting in the long range, to take the storm out to sea before impacting anyone.  Thus, it will be a critical time when this storm becomes well developed. If it becomes a hurricane earlier than expected, the chances of a more southern track increase. After that, there is no way to know what will transpire.

  
For more kicks, forecast tracks out in time. Forecasts only, not gospel. Look how much Irene's track in the forecast changed every 6 hours until that was set in stone. A lot will depend on what happens THROUGH the next 72-96 hours.