458 
FXUS62 KMLB 131904
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
304 PM EDT Mon Sep 13 2021

.DISCUSSION...
Current...Pcpn largely in the form of showers will continue to push 
wwd across the area, becoming oriented over the western portion of 
the peninsula through late afternoon. Activity wl likely draw to a 
close across interior zones before or near sunset. The forecast wl 
maintain sct showers and isolated storms offshore and over the Gulf 
Stream sections of the Space and Treasure coasts overnight, with 
skies becoming partly cloudy. Overnight lows in the mid-70s. 
Although, some areas along the immediate coast could struggle to 
fall out of the upper 70s, thanks to easterly flow.

from prev disc... 
Tue-Wed...At the surface weak high pressure just off of the mid 
Atlc coast will remain situated north of FL. TC Nicholas across 
northeast TX will gradually weaken as it ventures inland the upper
TX coast and Louisiana, with remnants getting pulled 
northeastward into an upper trough traversing the Upper Midwest, 
Ohio, and Tennessee Valleys. Onshore flow (ERLY) will persist on 
Tue with winds more SERLY on Wed. In the evenings and overnight 
light southerly to SSW winds will exist. Also of interest is the 
weak tropical wave initially just east of the Bahamas. This 
feature will continue to migrate NW/NNW with center of circulation
well away from ECFL and off of the southeast U.S. coast by 
sunrise Thu morning. The NHC continues to give this system a 50pct
chance to develop over the next 5 days. Deepest moisture remains 
forecast across western FL and the adjacent GoMEX, but PWAT values
will average 1.80-2.00 inches into mid-week across ECFL. For the 
moment, have deviated very little from the ongoing fcst with 
50-60pct PoPs each day (Tue/Wed) mainly for aftn/evening. A small 
threat will exist at night along the coast and the adjacent 
coastal waters. Highs continue in the U80s near the coast and L90s
inland. Overnight lows mild and in the L-M70s interior with some 
U70s within reach for the immediate Space/Treasure coasts. 

Thu-Sun...Upper ridging over the western Atlc expands (retrogrades) 
its reach toward the FL peninsula with mid-level heights increasing 
during the period. Mid-level temps relatively warm at -5.5C to -
6.5C. Ample moisture continues over the area during this time. The 
onshore flow will become fairly deep again by Fri-Sun, though speeds 
relatively light. Will continue with SCT-NMRS shower wording and SCT 
lightning storms each afternoon/early evening. However, the deeper 
onshore flow would favor greatest precip opportunity over the 
interior in the afternoon/evening and along the coast 
overnight/morning periods. Afternoon highs remaining in the U80s to 
L90s, with morning lows in the M-U70s.

&&

.AVIATION...
VFR conditions outside of convection expected through the  
period. Scattered showers and storms are ongoing, mainly across 
the south, from MCO-SUA. Prevailing VCTS everywhere except DAB. 
Kept TEMPO group for KLEE starting at 20Z for MVFR VIS. As of now,
confidence is not high enough to include other TEMPO groups at 
this time, however will monitor and add if necessary. Convection 
will push to the western half of the peninsula in the late 
afternoon and evening. However, showers and thunderstorms will, 
again, remain possible along the coast overnight. E winds 
remaining around 10kts or less this afternoon before decreasing to
5 KT or less overnight. Winds tomorrow will be east to east- 
southeast and increasing to around 5-10 KT in the afternoon. 

&&

.MARINE...A high pressure ridge axis remaining well north of the 
local area will continue a light easterly onshore flow across the
local Atlantic waters. Winds remaining around 10kts or less with 
briefly higher winds and seas near iso/sct storms. Showers and a 
few storms will remain possible through the overnight hours 
tonight, onshore flow will prevent any convection from drifting 
from the interior back towards the coast this afternoon. Seas 
2-3ft.

Tue-Fri...High pressure ridging remains situated north of the local 
waters thru the period. A weak tropical disturbance east of the 
Bahamas will remain well away from the local waters and move NNW/NW 
parallel to the local waters on Wed/early Thu. ERLY flow on Tue will 
become SERLY on Wed-Fri. Each evening/overnight the winds may veer 
to more S/SSW. Wind speeds will remain generally AOB 12 kts. 
Scattered showers remain forecast with ISOLD-SCT lightning storms as 
well. Seas 2-3 ft.

&&

.HYDROLOGY...Depending largely on tidal influence, the St. Johns 
River at Astor is forecast to briefly near Action Stage (2.0 ft) 
this afternoon, before falling again to just below through the 
end of the week. However, any heavy rainfall during this time 
could lead to additional height rises.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  74  89  75  89 /  20  40  20  50 
MCO  74  92  75  91 /  20  60  10  60 
MLB  77  89  76  89 /  20  40  20  60 
VRB  75  89  75  90 /  30  50  20  60 
LEE  74  93  75  92 /  20  60  10  60 
SFB  74  91  75  91 /  20  50  20  60 
ORL  74  91  75  91 /  20  60  10  60 
FPR  73  88  73  89 /  30  50  20  60 

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.

&&

$$

SHORT TERM...Pendergrast
LONG TERM....Combs
AVIATION...Watson