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000 
FXUS62 KMLB 112140
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
440 PM EST Wed Dec 11 2019

.DISCUSSION...
Tonight-Thursday...

Cold front extending from Lake-K to Cape Canaveral will stall in the 
vicinity of Lake-O/Jupiter Inlet where it will begin to wash out. 
N/NE wind surge will work its way down the Space/Treasure Coasts by 
arnd midnight and will continue thru the day on Thu as the post 
frontal ridge lifts off the Mid Atlc coast and into the NW Atlc. 
Meanwhile the front's trailing moisture band gradually saturates the 
H100-H85 lyr. Rainfall with the front has been largely absent, and 
latest RUC40 analysis shows the mid lvl drying out behind the front. 
PWat values btwn 1.50"-1.75", most of which is either trapped blo an 
H100-H85 frontal inversion or abv H30. 

The brisk onshore flow and saturated H100-H85 will require PoPs 
areawide, but the frontal inversion will limit them to low-topped 
nature that will generate light to moderate rain...QPF largely blo 
0.10", except btwn 0.10"-0.25" in the vicinity of the front. Highest 
PoPs along the coast south of the Cape (50-60pct)...decreasing to 20-
30pct north of I-4. Little in the way of cool air advection with 
this front...min temps in the U50s/L60s north of I-4...L70s Space 
and Treasure Coasts. Thu max temps in the M/U70s. 

Winds at the St. Aug coastal C-MAN site have reached sustained 
25KTS. This winds are expected to work their way down the 
Volusia/Brevard coasts overnight, mainly impacting the barrier 
islands...Wind Advisory in effect thru Thu.  

Friday-Sunday...(Amended Previous Discussion)
The stalled frontal boundary over ECFL lifts back north into north 
Florida as a low pressure wave develops over the northeast GOMEX on 
Friday, then slides northeast towards the Carolinas Friday night. 
This low will drag a weak cool front back south across the CWA 
Saturday afternoon-evening. Weak "bubble" high pressure ridge builds 
into the area late Saturday through Sunday, bringing drier and 
slightly cooler air to the region.

Increased moisture across the area leading to higher rain chances 
(40-50) with lower chances along the Kissimmee River and near Lake 
Okeechobee (20-30 percent). Model sounding analysis indicate low 
convective potential, so kept thunderstorms out of the forecast. 
Slightly above normal afternoon temps will continue through 
Saturday, falling back closer to climo Saturday night through Sunday 
night. Morning lows stay mild in the low to mid 60s Friday and 
Saturday mornings. 

Monday-Tuesday...(Amended Previous Discussion)
The next mid level short wave trough moves across the northern tier 
of the central-eastern CONUS through the period. While the ECM/CMC 
have a much stronger southern extension to the trough compared to 
the GFS, all of the models push another strong cold front into 
Florida by Tuesday night, preceded by a band of showers. Dry/warm wx 
Monday, then turning wet on Tuesday before cooling down Tuesday 
night into Wednesday.

&&

.AVIATION...Thru 12/18Z.
Sfc Winds: Thru 12/03Z...N/NE 12-16KTS with sfc G18-23KTS. Btwn 
12/3Z-12/06Z...bcmg E/NE 9-13KTS. Btwn 12/12Z-12/15Z...bcmg E/NE 
13-18KTS with sfc G18-23KTS.

Vsbys/WX/Cigs: Thru 12/00Z...N of KISM-KMLB prevailing MVFR cigs 
btwn FL015-025 areas IFR cigs btwn FL006-009 lcl MVFR cigs in BR...S 
of KISM KMLB areas MVFR cigs btwn FL020-030 lcl IFR cigs btwn FL006-
009...chc MVFR shras. 

Btwn 12/00Z-12/06Z..prevailing MVFR cigs btwn FL015-025 areas IFR 
cigs btwn FL006-009 lcl MVFR cigs in BR...E of KMLB-KOBE MVFR shras 
lkly...W of KMLB-KOBE chc MVFR shras.

Btwn 12/06Z-12/12Z...S of KISM-KMLB prevailing IFR cigs btwn FL006-
009 lcl MVFR cigs in BR chc of MVFR shras...N of KISM-KMLB N of KISM-
KMLB prevailing MVFR cigs btwn FL020-030 areas IFR cigs btwn FL006-
009. 

Aft 12/12Z...prevailing MVFR cigs btwn FL020-030 lcl IFR cigs btwn 
FL006-009...E of KMLB-KOBE MVFR shras lkly...W of KMLB-KOBE chc MVFR 
shras. 

&&

.MARINE...
Tonight...Cold front has pushed south of Ponce Inlet as was 
approaching Port Canaveral as of mid aftn...N/NE winds gusting to 
arnd 20KTS post fropa...steady arnd 10KTS pre fropa. Dangerous 
boating conditions dvlpg overnight as the front presses thru central 
FL to stall in the vicinity of Lake-O/Jupiter Inlet. Winds bcmg a 
fresh to strong NE breeze areawide with ocnl gusts near gale force 
over the offshore leg. Seas building to 6-9FT nearshore and 8-12FT 
offshore. Shras likely from the Cape southward...chc shras 
northward. Criteria is a notch or two blo gale warning criteria... 
will stick with the SCA. 

Thursday...Hazardous boating conditions continue as the post frontal 
wind surge continues. Winds bcmg a fresh to strong E/NE breeze by 
midday, then slowly diminishing to a E breeze by sunset. No sig 
change to seas as the easterly fetch will extend well into the open 
Atlc and will push a large easterly swell into the east FL coast. 
Seas 6-9FT nearshore and 8-11FT offshore. Shras likely from the Cape 
southward...chc shras northward. 

Friday...Hazardous boating conditions continue through Friday 
afternoon. East-northeast winds 20-25 knots late Thursday decrease 
to near 15 knots and become southeast by late Friday morning. 
Nearshore seas 7-9 feet and offshore seas 9-11 feet late Thursday 
diminish to 5-7 feet nearshore and 7-8 feet offshore by around noon 
Friday. Seas will likely linger after the winds decrease, thus may 
need an extension to the Small Craft Advisory into the evening. 

Saturday-Sunday...Winds diminish to less than 15 knots as they veer 
south-southwest ahead of the developing weather system and attendant 
cold front, which will pass through the local waters Saturday 
afternoon-evening. Seas 4-6 feet on Saturday subside to 3-5 feet 
Sunday.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  63  73  63  75 /  30  50  50  50 
MCO  63  78  64  78 /  30  40  40  40 
MLB  70  77  67  78 /  50  60  40  40 
VRB  71  78  64  79 /  60  70  40  40 
LEE  59  76  65  77 /  20  30  30  50 
SFB  62  77  64  77 /  30  40  40  50 
ORL  62  77  64  77 /  30  40  40  40 
FPR  71  77  65  80 /  60  70  40  40 

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...High Surf Advisory from 4 AM Thursday to 10 AM EST Friday for 
     Coastal Volusia-Indian River-Martin-Northern Brevard-
     Southern Brevard-St. Lucie.

     Wind Advisory until 3 PM EST Thursday for Coastal Volusia- 
     Northern Brevard.

AM...Small Craft Advisory until 4 AM EST Friday for Flagler Beach to 
     Volusia-Brevard County Line 0-20 nm-Volusia-Brevard County 
     Line to Sebastian Inlet 0-20 nm.

     Small Craft Advisory from 10 PM this evening to 3 PM EST Friday 
     for Sebastian Inlet to Jupiter Inlet 20-60 nm.

     Small Craft Advisory until 3 PM EST Friday for Flagler Beach to 
     Volusia-Brevard County Line 20-60 nm-Volusia-Brevard County 
     Line to Sebastian Inlet 20-60 nm.

     Small Craft Advisory from 10 PM this evening to 4 AM EST Friday 
     for Sebastian Inlet to Jupiter Inlet 0-20 nm.

&&

$$

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