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fxus64 khun 201852 aad 
afdhun 


Area forecast discussion...updated 
National Weather Service Huntsville Alabama 
152 PM CDT Sat Mar 20 2010 


Update... 


Current temperatures...particularly north of the Tennessee 
River...are already higher than previously thought. With some 
weak warm air advection ongoing...despite higher middle level 
convective cloud development...have decided to up high 
temperatures into the lower 70s across much of the area. Some 
isolated cooler spots...such as northwestern Lawrence County and 
some higher elevations could still just reach 68 or 69 degrees. 
Otherwise...will just clean up cloud cover wording to mostly 
cloudy everywhere. 


&& 


Aviation... /issued 1220 PM CDT Sat Mar 20 2010/ 


Aviation... broken to overcast VFR ceilings will redevelop early this 
afternoon at both taf sites. These conditions will deteriorate to 
MVFR ceilings or visibilities by 12z at kmsl and 13z at khsv on Sunday. This 
will be just ahead of the main area of rain showers ahead of an 
approaching storm system pushing into kmsl around 14z and khsv 
around 16z. These MVFR conditions will last through the end of the 
taf period. A few -shra may push into both taf sites as early as 
13z. 


Previous discussion... /issued at 1104 CDT Sat Mar 20 2010/ 


Cloud cover will be the key to the high temperature forecast today. 
A large area of high clouds continues to remain over southern 
middle Tennessee and many counties north of the Tennessee River. This shows 
signs of thinning over the last hour. Believe this erosion will 
continue over the remainder of the morning hours. However...these 
clouds have already made an impact on high temperatures today...since 
they were in place since daybreak...particularly across northwest 
Alabama eastward to Huntsville. Therefore...lowered high temperatures 
to the middle to upper 60s in locations most affected by cloud 
cover. Decent lapse rates this afternoon should keep high 
temperatures in the elevated locations a little cooler...lower to 
middle 60s...as well. Think we will see some low 70s on the southern 
edge of our forecast area...since they should see the most 
sunshine. 


Believe additional clouds will develop later this afternoon...as 
the cloud cover currently over southern Alabama moves northward. I 
expect most of the area to become mostly cloudy again after 1 or 2 
PM. Otherwise...winds will pick up from the south this 
afternoon...but should only increase to around 10 miles per hour. 


Spring officially begins today at 1232 CDT. Temperatures will be 
around 5 degrees above normal in locations which reach 70 degrees 
or higher. Thus...a nice start after a cold winter. 


&& 


Hun watches/warnings/advisories... 
Alabama...none. 
Tennessee...none. 
&& 


$$ 


Discussion...20 
previous discussion...20