169 
fxus64 klix 192054 
afdlix 


Area forecast discussion 
National Weather Service New Orleans la 
354 PM CDT Tuesday Aug 19 2008 


Discussion... 
radar shows large coverage across much of southeast Louisiana and 
southwest Mississippi...not quite as much across the coastal 
counties this afternoon. Rainfall behavior has been for steady 
moving higher reflectivity then a spreading out of moderate 
rainfall as the column saturates and anvils fan out. 
Fortunately...it appears the heaviest rains have been progressive 
yet some spots may have gotten between 1 and 3 inches...like 
around Abita Springs...Lake Catherine and near Thibodaux. The 
heaviest amounts may have fallen near the coast around Dulac and 
Cocodrie earlier this afternoon. 


Abundant moisture and lift from upper level low pressure system 
spinning over Texas will maintain an efficient rain process 
through at least Thursday. Forecast certainty decreasing bey0nd 
Thursday as much of the forecast will become influenced by future 
track of Tropical Storm Fay...which is holding its own over South 
Florida this afternoon. The track may become erratic in the next 
few days with little steering influences before upper ridge builds 
to the north of the system and causes a more distinctive westward 
motion in time. Combining the influences of the Texas low and 
whatever becomes of Fay would suggest a weak wind field or col 
developing overhead in our forecast area going into the weekend. 
This may produce a flood potential due to efficient warm rain 
processes not really handled well by the numerical models. Will 
indicate higher than normal rain chances for Wednesday...around 
40-50 percent for Thursday then hold around 40 percent each day 
Friday and beyond...conceding that one day or another may need 
significant adjusting given Fay's fate. No need for any flood 
watches at this time but something to be considered for upcoming 
days. 


&& 


Aviation... 
considerable convection across the forecast area will continue to 
threaten each of the taf sites through the afternoon and into the 
early evening hours. Otherwise...generally VFR conditions are 
expected through Wednesday morning although MVFR visibilities due to 
fog may develop at kmcb...kbtr and kgpt from about 08z to 13z 
Wednesday. 11 


Marine... 


Generally light winds are expected across the coastal waters through 
Friday. Depending on the exact path of Fay once it makes its shift 
back to the west after briefly entering the Atlantic off the coast 
of Florida...winds and seas may pick up somewhat across the coastal 
waters over the weekend. 11 


&& 


Preliminary point temps/pops... 
mcb 72 87 72 91 / 40 70 40 50 
btr 75 87 73 91 / 40 70 40 50 
msy 76 87 76 91 / 40 50 30 40 
gpt 76 87 77 90 / 40 50 30 40 


&& 


Lix watches/warnings/advisories... 
la...none. 
GM...none. 
MS...none. 
GM...none. 
&& 


$$ 


24/11