801 
fxus62 kjax 211425 
afdjax 


Area forecast discussion 
National Weather Service Jacksonville Florida 
1025 am EDT sun Mar 21 2010 


Update...light rain is spreading over the forecast area ahead of 
a frontal boundary traversing the Gulf of Mexico. Lightning has 
been mostly absent as the shower activity pushes inland. However a 
band of storms in the eastern Gulf should hold together better as it 
moves over the extreme southern tier. Although instability is meager... 
an influx of moisture and a strong (120 kt) jet stream aloft will 
provide large scale ascent necessary to maintain categorical probability of precipitation 
as a weak cold front moves across the forecast area this afternoon. Per Storm Prediction Center 
there is a better chance for thunderstorms this afternoon as the front 
approaches the East Coast after a few hours of heating. Also a southerly 
low level jet (~50 kt) will set up during the day. Surface winds are 
expected to be 10-15 miles per hour but with strong winds above the surface... 
there is a potential for strong wind gusts. The bulk of the rain 
is expected to depart by sunset. 


&& 


Aviation...despite line of rain showers moving in ahead of 
schedule...sites remain VFR at this hour but main band of embedded 
thunderstorms and rain remains west of the area. As this line pushes 
through...expect ceilings to lower to MVFR at gnv first and then the 
remaining sites by 15z-17z. After the line pushes through...expect 
ceilings to lower further with IFR likely at all sites and winds will 
increase through the early evening hours with gusts approaching 30 knots. 


&& 


Marine...winds have been slow to respond at area buoys this 
morning to approaching low level jet. Starting to see the first 
indications of a surge over mlb's buoys at this hour and expect 
this to quickly move northward this afternoon. Have pushed back 
start time of Small Craft Advisory for the offshore portion...otherwise forecast is 
on track. 


&& 


Preliminary point temps/pops... 
amg 68 47 64 43 / 70 20 20 10 
ssi 66 51 63 46 / 80 30 10 10 
jax 71 50 66 46 / 80 20 20 10 
sgj 71 53 65 50 / 80 30 10 10 
gnv 73 47 67 44 / 80 20 10 10 
ocf 75 49 70 46 / 80 20 10 10 


&& 


Jax watches/warnings/advisories... 
Florida...none. 
Georgia...none. 
Am...Small Craft Advisory until 8 am EDT Monday for Fernandina Beach 
to St Augustine Florida 20 nm to 60 nm offshore-St Augustine to 
Flagler Beach Florida 20 nm to 60 nm offshore. 


Small Craft Advisory from 5 PM this afternoon to 8 am EDT Monday 
for Altamaha Sound Georgia to Fernandina Beach Florida 20 nm to 60 nm 
offshore. 


&& 


$$ 


Mkt/jtd/pk