752 
fxus62 kmlb 071850 
afdmlb 


Area forecast discussion 
National Weather Service Melbourne Florida 
250 PM EDT Thursday Aug 7 2008 


Discussion... 


Aside from brief/isolated thunderstorms and rain showers forming near the East Coast sea 
breeze...the weather pattern has been hot and dry. A 15z sounding from 
kxmr showed an increase in relative humidity below 850 mb...but drier air aloft combined 
with weak middle/upper level forcing mechanisms are putting a strong cap on 
total convective activity. 


With such strong suppression in place...will keep the forecast dry 
overnight. Light SW flow overnight will couple with increasing high 
level clouds to keep min temperatures in the m70s...~3-5f degree above climatology. 


A major change in the regional weather pattern will occur through Friday as the 
the much-advertised short wave trough over the eastern Continental U.S. Continues to 
develop overnight. As it does...it will push the dlm Atlantic ridge 
axis into the Florida Straits by daybreak...which will increase the mean 
flow through the h100-h50 layer out of the W/SW. 


Meanwhile...a strong h100-h70 ridge over the northern plains will push 
into the upper Midwest and amplify the wave pattern significantly. 
Short range guidance suggests near perfect meridional flow over the 
appalachian/Great Lakes regions by daybreak Friday. This will push a 
frontal boundary from the southern appalachian range well into the deep 
S. Moisture pooling within the trough will couple with the increasing 
west/SW flow will return east central Florida to a wet weather pattern to end the 
work week. Scattered/numerous rain showers/thunderstorms expected while increasing clouds 
will drop maximum temperatures back to more climatology levels. 


Sat-sun...axis of unseasonably strong longwave trough over the 
eastern U.S. Will slowly migrate east of the state. Highest rain 
chances looks to be Sat with trough forecasted to sink to central 
Florida before stalling. Feature will remain as a focus point for 
development of numerous showers and storms over north and central 
Florida as high moisture and favorable westerly flow in place...creating 
potential for locally heavy rains. Showers and storms will linger 
into the evening while drifting offshore. Some drying Sunday from 
north-S as high pressure builds into the southeast behind departing 
system. Probability of precipitation reduced with higher coverage south where moisture 
remains highest. 


Mon-Wed...model is trending drier this period. Despite westerly 
flow which is usually favorable for rain along the Florida East 
Coast...drier air forecast to overspread much of central Florida Monday on 
only gradually modify Tuesday and Wednesday. Will carry 30% Monday and 40% Tuesday 
and Wednesday but this may be generous. 


&& 


Aviation...wndshft from west/SW to east/southeast over the coastal counties in 
the vicinity of I-95 as the East Coast seabreeze pushes inland. 
Brief isolated rain showers/thunderstorms and rain showers through 00z but the chances of these 
affecting any of the aerodromes is too remote to include them in 
the tafs...will handle with amds. VFR all sites 00z-14z with ceilings 
at or above fl120 developing overnight. 


&& 


Marine...sfc/bndry layer flow will increase out of the west/SW through 
Friday as the Atlantic ridge axis is pushed into the Florida Straits by 
the short wave trough developing over the eastern Continental U.S.. seas will 
respond by building up to 3ft over the nearshore waters and 3-4ft 
offshore. Scattered/numerous rain showers/thunderstorms and rain showers will develop over the Central 
Peninsula and move offshore as a surface front pushes into the deep S 
on Friday. 


Light westerly flow Friday will increase early Saturday with approach 
of frontal trough. Winds and seas will be aggravated by storms 
moving offshore Saturday and Sunday. Wind waves offshore will 
likely reach 3 to 4 feet beyond 20 nm during the weekend with lower 
seas heights near the immediate coast. 


&& 


Preliminary point temps/pops... 
dab 76 90 74 89 / 10 70 30 60 
mco 75 93 74 89 / 10 70 30 60 
mlb 76 91 71 89 / 10 60 30 60 
vrb 76 90 74 90 / 10 60 30 50 


&& 


Mlb watches/warnings/advisories... 
Florida...none. 
Am...none. 


&& 


$$ 


Short term/aviation...bragaw 
long term....Kelly