Chance Of On-Schedule Shuttle Launch Bleak, Umbrella Stands to Flourish

Inverted trough with weak, not quite closed low circulation over the Bahamas. Tropical wave extends NNE-NE from near Honduras.  Persistent upper level low over North Central Gulf to gradually drift WNW through Saturday. Circulation around the base of this low provides abundant upper level cloud coverage, persistent. Any low to form appears will take a journey toward coastal North Carolina while a combined Florida Spine of the State trough merges with moisture from decayed tropical wave./inverted trough Thursday - Sunday over Florida. Net effect is rain and some thunderstorms, primarily Friday and Saturday (and beyond......)

SYNOPSIS AND WHAT'S "ON TAP": For one, it's not beer. It's water aplenty in the atmosphere. The word of the next 7-10 days is PWAT...Precipitable Water Values. Values ranging from 1.75 - 2.30" is on the 'normal wet season level to high end tropical like".  Tropical wave/ inverted trough will enter Southeast Florida beginning tonight. High precipitable water values of 2.00" are already over some of South Florida, but of this attributed to moisture in the upper levels. Rainshowers are already around much of the keys and far SE Florida. Believe most of this activity will remain over South Florida today and enter portions of South Central later in the day. Umbrellas, goggles, and snorkels required to breath outside by Friday over much of the state, wet suits - optional.


DAY'S AHEAD: There is a near stationary front near the mid-Atlantic Region as well as a trough axis running south down the lee of the Appalachian Chain. This trough could extend into North Florida later today and be the impetus for thunderstorms over North Florida near I-10 toward Gainesville.  This front is expected, as noted two posts ago, to sink south into the weekend toward North Central Georgia. As the tropical wave is lifted north and low level ridge axis  builds in behind it across South Florida, providing for a SSW-SW Florida at the low levels through at least Saturday.  Beyond that point in time, the front may sink further south later in the week toward next weekend as the ridge axis lifts toward Central Florida. This would favor the I-4 Corridor and south toward North Brevard County for afternoon thunderstorms while South Florida dries out with isolated diurnally driven convection possible far removed from the frontal boundary and deeper moisture. A portion of yet another tropical wave now far away could possibly provide more moisture for South Florida heading toward NEXT weekend.


TODAY: Upper level low remains over the Gulf of Mexico, providing for SW flow way up there in the atmosphere around 25,000 Ft. Cloud tops of showers and storms in the SW Gulf combined with diffluence aloft in the Eastern Gulf periodically results in enhanced period of Cirrus Clouds over much of the state.  Deepest moisture should be able to reach as far north as Martin County/Indian River County line  by sunset tonight, continuing to progress northward over night and approaching the Beach Line to Orlando to Tampa line near sunrise Thursday.


Rain showers and thunderstorms (mostly rain showers except as noted below) will cover much of South Florida by mid-afternoon. Believe extensive cloud coverage from there on out will leave the area cloud covered with dwindling light rain late this afternoon due to early onset of convective showers and thunder.  Other showers might be able to make it onshore the SE Coast, emanating from the SW Bahamas. Outflows and continued most unstable atmospheric feed from the Gulf could continue some thunder chances near the SW Florida Coast. Meanwhile, outflows could also spread moisture northward, resulting in a late afternoon shower or thunderstorm in interior portions of Okeechobee or far Southern Osceola County toward Indian River County (although not sketched in).

Green line shows in general the northern extent of rain chances up through 7pm. Showers/Storms over North Florida not associated with the weather occurring over South Florida today. Elsewhere, high clouds, and some cumulus mainly inland. Some spotty showers could form in other locations, but would be of such isolated nature I didn't bother trying to sketch those in.

TONIGHT/THURSDAY: Over night, showers could regenerate near either coast of SE/SW Florida and work northward to the Cape area at sunrise. Thursday appears could hold promise for higher rainfall totals as far north as the aforementioned "magic dividing line" primarily near the coast from eventually Daytona Beach south to Miami and along the SW Florida region.


FRIDAY:  Pattern Change / New Wardrobe Day: Whatever is left of the 'wave' over Florida will have pretty much washed out, but in its wake will be high levels of PWAT air from top to bottom. Expect that such levels of moisture in the atmosphere will hold residual cloudiness over the state Friday and all day for the moist (most) part. Some models are actually showing it to be raining at the Launch Pads prior to launch and throughout the launch window. Regardless, there will be lots of clouds around either way. So, if it were to launch, it will be brief to actually witness.


LAUNCH: As noted over a week ago, it still remains 'yet to be seen' for a launch. And if it does launch, good luck seeing it beyond 20 seconds. Rainfall Thursday will likely leave remnant cloud coverage, extensively so. Given the PWAT values (over 2.00") and forecast temperatures reaching in the mid 80Fs (at lease), combined with very low Lifting Condensation Levels, Lifting Condensation Levels, and convective temperatures in the low-mid 80Fs..convective type clouds can form with the first hints of day break. This should be the case  Friday and Saturday.
Beyond Saturday, convection should begin more  toward noon. That, combined with an earlier launch time would make launch more probable on Sunday..if it hasn't gone already. But debris clouds will remain to hamper a respectable, videographic view other than from right on the Center Proper from a Press Stand. The better chances for tourists and locals from far and near to actually get their money's worth (up to $3000.00 I hear, dang greedy scalpers) will begin on Tuesday or Wednesday as we enter a more solid diurnally driven convective regime and as higher PWAT, flippers-n-snorkel air shifts to just north of the Cape area.

SATURDAY: More residual cloudiness to start, with thunderstorms and  rain showers beginning late morning through late night. There actually could be showers somewhere over the state at any time between Friday afternoon and Saturday afternoon, but of greatest coverage and strength from noon time through 6pm. 


SUNDAY:  Might be the first better chances for a launch, but personally, would like to have them wait until Tuesday or Wednesday as the deepest moisture by then has cleared South Florida and will be near and NORTH of the Magic Dividing line of the state (Dead Central, East to West), to nearly clear of the Space Coast.


NEXT WEEK: As noted yesterday, next week's weather appears will be dictated by a low level ridge axis running somewhere across South Central to Dead Central Florida. This will favor the I-4 Corridor toward just north of the Beachline east of Orlando for afternoon and evening thunderstorms with continued High PWAT Air in place. Additionally, the surface frontal boundary will be located over North Central Georgia, possibly sinking toward South Georgia during the week toward next weekend.  Latest guidance indicates a pronounced drier period for South Central and South Florida, although likely not as dry as indicated. Sometime near the end of next weekend, the ridge axis should sink further south toward far South Florida, when once again this area will be in for more diurnally driven thunderstorms, widespread and more lightning prolific.


NATURE OF ACTIVITY: Believe most of the activity will manifest as mostly heavy rainstorms with some lightning, although there could be some isolated but brief lightning makers. Expect that the heavier rainstorms will manifest AFTER the wave has cleared the area and the ridge axis across North Central Florida relocates in its wake across far South Florida on Friday and Saturday, with activity decreasing along the east coast from South to North heading toward Tuesday, but with thunderstorms continuing toward far North Brevard to JAX and the Panhandle region for many days to come after Friday or Saturday. Severe weather is not expected due to the warm, tropical like temperatures aloft; some fairly steep (unstable) low level lapse rates will create the most prolific lightning making storms earlier in the day.


RAINFALL: Appears the overall heaviest rainfall totals, when all is said and done through Saturday evening will be over Far Southwest Florida and along the east coast from Martin County to St. Augustine, and possible a portion of the Panhandle Region. But most anywhere (with exceptions of course..probably where I live where it will barely rain at all)..can expect between 0.75" -2.-00" of rainfall, with isolated amounts possibly over 3.00". There is also the possibility that a location or  two will get 'zeroed in' on..and get over 6.00" by the end of Saturday or Sunday. Someone will win the 'rainfall jackpot'...TBD.