981 
fxus64 kshv 211639 
afdshv 


Area forecast discussion 
National Weather Service Shreveport la 
1039 am CST Sat Nov 21 2009 


Discussion... 
will make a few adjustments on a late morning forecast and grids 
update to bring the zone forecast and grids more in line with 
ongoing and expected weather for this afternoon. Have raised the 
probability of precipitation in the southeast zones for the afternoon because the upper 
level low over the Gulf Coast near Beaumont...and associated 
surface low out over the Gulf...are throwing abundant moisture 
north into East Texas and central Louisiana. This is causing 
consistent solid rainfall south of a line from Nacogdoches Texas 
to Clarks Louisiana. This rain should continue most of the 
afteroon in the same area...and taper off during the evening as the 
low pressure system moves east of the four state area. 


North of the Nacogdoches Texas to Clarks la line...the rain is more 
scattered and tends to dissipate as the rainfall over the 
south...moves north. Will go with a 60 pop in the mlu area...40 
percent at shv...and 30 at tyr for the afternoon. In Arkansas and 
southeast Oklahoma 20 and 30 percent probability of precipitation should be sufficient for 
the afternoon. Only a few light showers area anticipated for those 
areas. All the rainfall should move east during the evening...and 
out of the four state area. 


Temperatures are a little warmer than earlier forecast for this 
afternoon...so have upped that maximum temperatures for this afternoon 
one category in the east zones. 


No other changes to previous forecast were made. 


&& 


Aviation... 
surface low out over the Gulf is well offshore and slowly moving 
eastward. The upper low is over southeast Texas and shifting the winds 
aloft...but speeds are generally less than 30 kts below fl240. 
Moisture wrapping around the low is mostly in the middle levels with 
VFR continuing for all but klfk where moderate rain is falling at this time. 
Ceilings are dropping a bit in the wake of the low...but will keep close 
to VFR daylight...but may go south overnight. Surface winds are light 
north/NE for our terminals and will keep less than 10 kts. Look for 
the rain clouds to part overnight as the low moves out...but IFR 
ceilings/visibility may develop generally along and south of I-20 overnight 
and for early daylight on Sunday. Improvements by lunch as weak 1017 
mb high pressure builds in over Texas. 
/24/ 


&& 


Preliminary point temps/pops... 
shv 60 45 64 43 70 / 40 30 10 0 10 
mlu 58 47 63 43 68 / 60 40 20 0 10 
deq 61 41 65 42 67 / 20 20 0 0 10 
txk 60 45 64 42 69 / 30 30 0 0 10 
eld 60 45 64 42 69 / 30 40 10 0 10 
tyr 60 44 67 45 71 / 30 20 0 0 10 
ggg 60 43 65 44 71 / 40 20 0 0 10 
lfk 58 44 67 44 72 / 60 20 0 0 10 


&& 


Shv watches/warnings/advisories... 
Arkansas...none. 
La...none. 
OK...none. 
Texas...none. 
&& 


$$ 


03/24